As filed with the Securities and Exchange Commission on October 10, 2023

Registration No. 333-272567 

UNITED STATES SECURITIES AND EXCHANGE COMMISSION 

WASHINGTON, D.C. 20549

PRE-EFFECTIVE AMENDMENT NO. 6 TO THE

FORM S-1

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

NB Bancorp, Inc.

Needham Bank 401(k) Plan 

(Exact Name of Registrant as Specified in Its Charter)

Maryland	6036	93-2560883
(State or Other Jurisdiction of	(Primary Standard Industrial	(I.R.S. Employer
Incorporation or Organization)	Classification Code Number)	Identification Number)

1063 Great Plain Avenue 

Needham, Massachusetts 02492 

(781) 444-2100 

(Address, Including Zip Code, and Telephone Number, Including Area Code, of Registrant’s Principal Executive Offices)

Joseph P. Campanelli 

President, Chief Executive Officer 

and Chairman of the Board 

NB Bancorp, Inc. 

1063 Great Plain Avenue 

Needham, Massachusetts 02492 

(781) 444-2100 

(Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent for Service)

Copies to:

Steven Lanter, Esq.	Samantha M. Kirby, Esq.
Lawrence M.F. Spaccasi, Esq.	Goodwin Procter LLP
Luse Gorman, PC	100 Northern Avenue
5335 Wisconsin Avenue, N.W.	Boston, MA 02210
Suite 780	(617) 570-1000
Washington, D.C. 20015
(202) 274-2004

Approximate date of commencement of proposed sale to the public: As soon as practicable after this registration statement becomes effective.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, check the following box: x

If this Form is filed to register additional shares for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering: ¨

If this Form is a post-effective amendment filed pursuant to Rule 462I under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering: ¨

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering: ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act:

Large accelerated filer	¨	Accelerated filer	¨
Non-accelerated filer	x	Smaller reporting company	¨
		Emerging growth company	x

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act: ¨

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

Prospectus Supplement

 

Interests in

 

NEEDHAM BANK 401(k) PLAN

 

Offering of Participation Interests of up to 4,960,975 Shares of

 

NB BANCORP, INC.

 

Common Stock

 

In connection with the mutual to stock conversion of NB Financial, MHC, NB Bancorp, Inc., a newly-formed Maryland corporation and the to be holding company of Needham Bank, is offering shares of its common stock for sale at $10.00 per share. Following the offering, it is expected that shares of NB Bancorp, Inc. common stock will be listed on the Nasdaq Capital Markets under the symbol “NBBK.”

 

In connection with the stock offering, Needham Bank is allowing participants in the Needham Bank 401(k) Plan (the “401(k) Plan”) to invest all or a portion of their account balances in NB Bancorp common stock. This prospectus supplement relates to the election of 401(k) Plan participants to direct the trustees of the 401(k) Plan to invest up to 100% of their account balance in the 401(k) Plan in NB Bancorp, Inc. Common Stock at the time of the stock offering. Based upon the value of the 401(k) Plan assets at June 30, 2023, the trustees of the 401(k) Plan could purchase up to 4,960,975 shares of NB Bancorp common stock on behalf of participants, at the purchase price of $10.00 per share, in the stock offering.

 

Before you consider investing, you should read the prospectus of NB Bancorp, dated [date], 2023, which is attached to this prospectus supplement. It contains detailed information regarding the conversion, the stock offering of NB Bancorp and the financial condition, results of operations and business of Needham Bank. This prospectus supplement provides information regarding the 401(k) Plan. You should read this prospectus supplement together with the prospectus and keep both for future reference.

 

For a discussion of risks that you should consider, see “Risk Factors” beginning on page 15 of the attached prospectus, and “Notice of Your Rights Concerning Employer Securities” in this prospectus supplement.

 

The interests in the Plan and the offering of shares of NB Bancorp common stock have not been approved or disapproved by the Federal Deposit Insurance Corporation, the Massachusetts Commissioner of Banks, the Board of Governors of the Federal Reserve System, the Securities and Exchange Commission or any other federal or state agency. Any representation to the contrary is a criminal offense.

 

The securities offered by this prospectus supplement are not deposits or savings accounts and are not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.

 

This prospectus supplement may be used only in connection with offers and sales by NB Bancorp in the stock offering of NB Bancorp common stock that may be acquired within the 401(k) Plan. No one may use this prospectus supplement to reoffer or resell interests in shares of NB Bancorp common stock acquired through the 401(k) Plan.

 

You should rely only on the information contained in this prospectus supplement and the attached prospectus. NB Bancorp, Needham Bank and the 401(k) Plan have not authorized anyone to provide you with different information.

 

This prospectus supplement does not constitute an offer to sell or solicitation of an offer to buy any securities in any jurisdiction to any person to whom it is unlawful to make an offer or solicitation in that jurisdiction. Neither the delivery of this prospectus supplement and the attached prospectus nor any sale of NB Bancorp common stock shall under any circumstances imply that there has been no change in the affairs of NB Bancorp, Needham Bank or the 401(k) Plan since the date of this prospectus supplement, or that the information contained in this prospectus supplement or incorporated by reference is correct as of any time after the date of this prospectus supplement.

 

The date of this prospectus supplement is [date], 2023.

 

 

TABLE OF CONTENTS

 

THE OFFERING	S-1
Securities Offered	S-1
Election to Purchase NB Bancorp, Inc. Common Stock	S-1
Purchase Priorities	S-2
Purchases in the Offering and Oversubscriptions	S-3
Composition of the NB Bancorp, Inc. Stock Fund	S-3
Minimum and Maximum Investment	S-4
Value of the Plan Assets	S-4
How to Order Stock in the Offering	S-4
Order Deadline	S-6
Irrevocability of Transfer Direction	S-6
Future Direction to Purchase and Sell Common Stock	S-6
Voting Rights of Common Stock	S-7
DESCRIPTION OF THE 401(k) PLAN	S-7
Introduction	S-7
Eligibility and Participation	S-7
Contributions under the Plan	S-7
Limitations on Contributions	S-8
Benefits under the Plan	S-8
Investment of Contributions and Account Balances	S-9
Performance History	S-9
Description of the Investment Funds	S-10
NB Bancorp, Inc. Stock Fund	S-14
Withdrawals from the Plan	S-14
Administration of the Plan	S-14
Amendment and Termination	S-15
Merger, Consolidation or Transfer	S-15
Federal Income Tax Consequences	S-15
Notice of Your Rights Concerning Employer Securities	S-16
Additional ERISA Considerations	S-17
Securities and Exchange Commission Reporting and Short-Swing Profit Liability	S-17
Financial Information Regarding Plan Assets	S-17
LEGAL OPINION	S-17

 

 

THE OFFERING
Securities Offered	Needham Bank is offering participants in the 401(k) Plan the opportunity to purchase participation interests in shares of NB Bancorp, Inc. common stock through the 401(k) Plan. A “participation interest” represents your indirect ownership of a share of NB Bancorp, Inc. common stock that is acquired by the 401(k) Plan and is equivalent to one share of NB Bancorp common stock. In this prospectus supplement, “participation interests” are referred to as shares of  NB Bancorp common stock. At the stock offering purchase price of  $10.00 per share and allowing participants to use up to 100% of their account balances, the 401(k) Plan may acquire up to 4,960,975 shares of NB Bancorp, Inc. common stock in the stock offering, based on the approximate fair market value of the 401(k) Plan’s assets as of June 30, 2023.   Only employees of Needham Bank may become participants in the 401(k) Plan and only participants may purchase shares of NB Bancorp common stock through the 401(k) Plan. However, your investment in shares of NB Bancorp common stock in connection with the stock offering is subject to the purchase priorities listed below.   Information regarding to the 401(k) Plan is contained in this prospectus supplement and information with respect to the financial condition, results of operations and business of NB Bancorp and the Needham Bank is contained in the accompanying prospectus. The address of the corporate/main office of NB Bancorp and Needham Bank is 1063 Great Plain Avenue, Needham, Massachusetts 02492 and the telephone number at this address is (781) 444-2100.   Address questions about this prospectus supplement to Linda Farley, SVP, Human Resources/Learning & Development, Needham Bank, 1063 Great Plain Avenue, Needham, Massachusetts 02492; telephone number (781) 444-2100; email: lfarley@NeedhamBank.com.   Direct all questions about the stock offering, the prospectus, or obtaining a stock order form to purchase stock in the offering outside the 401(k) Plan to the Stock Information Center at 844-305-2265 (toll-free), Monday through Friday, 10:00 a.m. through 4:00 p.m., Eastern Time. The Stock Information Center will be closed on bank holidays.
Election to Purchase NB Bancorp, Inc. Common Stock	In connection with the stock offering, you may elect to designate a portion (up to 100%) of your 401(k) account balance to a money market fund called “Stock Purchase,” which will be used to subscribe for NB Bancorp common stock in the stock offering. In making this designation, you should carefully read the prospectus and this prospectus supplement and consider the information set forth on page S-16 of this prospectus supplement under “Notice of Your Rights Concerning Employer Securities — The Importance of Diversifying Your Retirement Savings.” The trustees of the NB Bancorp, Inc. Stock Fund will subscribe for the purchase of NB Bancorp common stock at $10.00 per share in accordance with your directions. However, your directions are subject to the purchase priorities and purchase limitations, as described below.

 

S-1

 

Purchase Priorities   All 401(k) Plan participants are eligible to elect to subscribe for NB Bancorp common stock in the stock offering. However, the elections are subject to the purchase priorities in the Plan of Conversion of NB Financial, MHC, which provides for a subscription offering and a community offering. In the stock offering, the purchase priorities are as follows and apply in case more shares of NB Bancorp common stock are ordered than are available for sale (an “oversubscription):   Subscription Offering:   (1)    Each person with aggregate account balances of $50 or more at Needham Bank as of the close of business on March 31, 2022, has first priority.   (2)    Each person with aggregate account balances of $50 or more at Needham Bank as of the close of business on June 9, 2023, has second priority.   (3)    Needham Bank’s tax-qualified plans, including the employee stock ownership plan and the 401(k) Plan, have third priority.   (4)    employees, officers, directors and corporators of Needham Bank, NB Financial, MHC, NB Financial, Inc. and NB Bancorp who do not have a higher purchase have fourth priority.   Community Offering:   Shares of NB Bancorp common stock not purchased in the subscription offering may be offered for sale to the general public in a “community offering,” with a preference given Shares of common stock not purchased in the subscription offering may be offered for sale to the general public in a community offering, with a preference given to natural persons (including trusts of natural persons) residing in the following Massachusetts towns and cities: in Norfolk County, the following cities and towns: Brookline, Dedham, Dover, Franklin, Medfield, Millis, Needham, Norfolk, Norwood, Walpole, Wellesley and Westwood; in Middlesex County, the following cities and towns: Arlington, Ashland, Belmont, Cambridge, Everett, Framingham, Holliston, Hopkinton, Malden, Medford, Medway, Natick, Newton, Sherborn, Somerville, Waltham, Watertown, Wayland and Weston; in Worcester County, the following cities and towns: Milford; and in Suffolk County, the following cities and towns: Boston and Chelsea.   If you fall into subscription offering categories (1), (2) or (4) above, you have subscription rights to purchase NB Bancorp common stock in the subscription offering and you may use funds (up to 100% of your account balance) in the 401(k) Plan to pay for the NB Bancorp common stock. You may also be able to purchase shares of NB Bancorp common stock in the subscription offering even though you are ineligible to purchase through subscription offering categories (1), (2) or (4) through subscription offering category (3), reserved for the Needham Bank’s tax-qualified employee plans.   If you fall into purchase priority (1), (2) or (4), you will separately receive offering materials in the mail, including a stock order form. You may use the stock order form to purchase shares of NB Bancorp common stock outside the 401(k) Plan.

 

S-2

 

	Additionally, instead of  (or in addition to) placing an order outside the 401(k) Plan using the stock order form, you may place an order for the purchase of NB Bancorp common stock through the 401(k) Plan in the manner described below under “How to Order Common Stock in the Stock Offering Through the Plan.”
Purchases in the Offering and Oversubscriptions	The trustees of the 401(k) Plan will subscribe for NB Bancorp common stock in the stock offering in accordance with your directions. Once you make your election, the amount that you elect to transfer from your existing investment options for the purchase of NB Bancorp common stock will be sold from your existing investment options and the proceeds will be transferred to the Stock Purchase option (which will be invested in a money market fund during the offering period) pending the completion of the stock offering several weeks later. After the end of the stock offering period, we will determine whether all or any portion of your order will be filled (if the offering is oversubscribed you may not receive any or all of your order, depending on your purchase priority, as described above). The amount that can be used toward your order will be applied to the purchase of NB Bancorp common stock. Following the closing of the stock offering, your purchased shares of NB Bancorp common stock will be transferred to the 401(k) Plan and will be reflected in your 401(k) Plan account as soon as practicable thereafter.   In the event the stock offering is oversubscribed, and the trustees are unable to use the full amount allocated by you to purchase NB Bancorp common stock in the stock offering, the amount that cannot be invested in shares of NB Bancorp common stock, and any interest earned on that amount, will be transferred from the Stock Purchase option and reinvested in the existing funds of the 401(k) Plan, in accordance with your then existing investment election (in proportion to your investment direction for future contributions). The prospectus describes the allocation procedures in the event of an oversubscription. If you choose not to direct the investment of your account balances towards the purchase of NB Bancorp common stock in connection with the stock offering, your account balances will remain in the investment funds of the 401(k) Plan as previously directed by you.

 

Composition of the NB Bancorp, Inc. Stock Fund Shares of NB Bancorp common stock purchased by the 401(k) Plan in the stock offering will be transferred to the 401(k) Plan and held in the NB Bancorp, Inc. Stock Fund. The NB Bancorp, Inc. Stock Fund is neither a mutual fund nor a diversified or managed investment option. Rather, it is merely a recordkeeping mechanism established by the 401(k) Plan custodian to track the shares purchased by the participants in the stock offering through the Plan. The NB Bancorp, Inc. Stock Fund will consist solely of shares of NB Bancorp common stock purchased by participants in the 401(k) Plan, which will be initially valued at $10.00 per share (i.e., the purchase price).   Following the stock offering, each day the aggregate value of NB Bancorp, Inc. Stock Fund will be determined by dividing the total market value of the fund at the end of the day by the total number of shares held in the fund by all participants as of the previous day’s end. The change in share value reflects the day’s change in stock price of NB Bancorp common stock, and the value of each participation interest should be the same as one share of NB Bancorp common stock.    Investment in NB Bancorp common stock involves risks common to investments in shares of stock. For a discussion of material risks you should consider, see the “Risk Factors” section of the accompanying prospectus and the section of the prospectus supplement called “Notice of Your Rights Concerning Employer Securities” (see below).

 

S-3

 

	The portion of your 401(k) Plan account invested in the NB Bancorp, Inc. Stock Fund will be reported to you on your regular 401(k) Plan participant statements. You can also go online at any time to www.principal.com or call 1-800-547-7754 to review your account balances.
Minimum and Maximum Investment	In connection with the stock offering, the 401(k) Plan will permit you to use up to 100% of your 401(k) Plan account balance for the purchase of NB Bancorp common stock in the stock offering.   The trustees of the 401(k) Plan will subscribe for shares of NB Bancorp common stock offered for sale in the stock offering, in accordance with each participant’s direction. The trustee will pay $10.00 per share, which will be the same price paid by all other persons who purchase shares in the stock offering. To purchase NB Bancorp common stock through the 401(k) Plan, the minimum investment is $250, which will purchase 25 shares. No individual may purchase more than $800,000 (80,000 shares) of NB Bancorp common stock. Furthermore, no person or entity, together with associates or persons acting in concert with such person or entity, may purchase more than $800,000 (80,000 shares) of NB Bancorp common stock in all categories of the stock offering combined. Please see the prospectus for further details regarding additional maximum purchase limits for investors in the stock offering.
Value of the Plan Assets	As of June 30, 2023, the market value of the assets of the 401(k) Plan attributable to active and former employees of Needham Bank was approximately $49,609,751.

 

How to Order Stock in the Offering	You can elect to transfer up to 100% of your current 401(k) Plan account balance (in whole dollar amounts) to the Stock Purchase option, which will be used by the 401(k) Plan trustees to purchase shares of NB Bancorp common stock. This is done by following the procedures described below. Please note the following conditions concerning this election:
	·      Your election is subject to a minimum purchase of 25 shares of common stock, which equals $250.
	Your election, plus any order you placed outside the 401(k) Plan, are together subject to a maximum purchase limit of no more than 80,000 shares of NB Bancorp common stock, which equals $800,000. The prospectus describes an additional purchase limitation of 80,000 shares of NB Bancorp common stock, which equals $800,000, for an individual, together with associates or persons acting in concert with such individual.
	·       The election period for the Plan purchases ends at 4:00 p.m., Eastern Time, on November 7, 2023 (the “Plan Purchase Period”).
	·      Your election to purchase common stock in the offering through the 401(k) Plan will be accepted by Principal Financial Group, the recordkeeper of the 401(k) Plan. After your election is accepted by Principal Financial Group, it will be rounded down to the closest dollar amount divisible by $10.00, and will be used by the trustees to purchase shares of NB Bancorp common stock sold in the stock offering. This difference will remain in the Stock Purchase option until the completion of the stock offering, which is expected to be several weeks after the Plan Purchase Period ends. At that time, the NB Bancorp common stock purchased based on your election will be transferred to the 401(k) Plan and any remaining funds will be transferred out of the Stock Purchase option for investment in other funds under the 401(k) Plan, based on your election currently on file for future contributions.

 

S-4

 

	·      The amount you elect to transfer to the Stock Purchase option will be held separately until the completion of the stock offering. Therefore, this money is not available for distributions, loans, or withdrawals until the stock offering is completed, which is expected to be several weeks after the 401(k) Plan Purchase Period ends.
	·      Following the completion of the stock offering, your purchased shares of NB Bancorp common stock will be reflected in your 401(k) Plan account through the NB Bancorp, Inc. Stock Fund.
	Follow these steps to make your election to use your account balance in the 401(k) Plan to purchase shares of NB Bancorp, Inc. common stock in the stock offering. You are allowed only one election to transfer funds to the Stock Purchase option.
	·      Go to www.principal.com and log into your 401(k) Plan account. In Account Login, click on drop down and choose “Personal,” then “GO.” Enter your Username and Password. If you haven’t established your Username and Password, click on the link “Establish your Username and Password” and follow the prompts.
	·      On your Personal Summary Page, choose the line for the Needham Bank 401(k) Savings and Investment Plan.
	·      When you reach “Your Account Overview,” click on “Investments” across the top navigation of the screen, and then click on “Change Investments.”
	·      When you reach the “Change Investments” screen, click on the box titled “Move Balances.” Then click on Make a Transfer.”
	·      Click on “Advanced Transfer Features” and choose “dollars,” then enter the amount you would like to transfer “From” each investment. When you have completed transferring “From” each investment, choose “Continue.”
	·      Enter the dollars that you will be transferring into the Stock Purchase account. The Stock Purchase account is a money market investment that will hold the funds until the stock offering is concluded. All of the funds that you transferred “From” other investments must be transferred to another investment. All of the dollars must be transferred “To” another investment.
	When you have completed the “To” portion of the transaction, click “Continue.” You will be taken to a confirmation page. Please review your transaction for accuracy. If you need to make changes, click on “Cancel” or “Start Over” or “Previous” to make changes. If the information is correct, click on the box, “I confirm the information above and authorize Principal Life Insurance Company to process this request.” You will receive a communication in your Message Center confirming your transaction.

 

S-5

 

	After you completed your online election, you will also need to complete the Stock Information Form and return it either using inter-office mail, emailing it to lfarley@NeedhamBank.com, by faxing it to 718-474-5883 or by delivering it in person, to be received by Linda Farley, SVP, Human Resources/Learning & Development, Needham Bank, 1063 Great Plain Avenue, Needham, Massachusetts 02492; telephone number (781) 444-2100; email: lfarley@NeedhamBank.com.
Order Deadline	You must make your election online at www.principal.com and return your Stock Information Form by inter-office mail, by emailing to lfarley@NeedhamBank.com, by faxing it to 718-474-5883 or by delivering it in person to Linda Farley, SVP, Human Resources/Learning & Development, Needham Bank, 1063 Great Plain Avenue, Needham, Massachusetts 02492; telephone number (781) 444-2100; email: lfarley@NeedhamBank.com; to be received no later than 4:00 p.m., Eastern Time, on November 7, 2023.
Irrevocability of Transfer Direction	Once you make an election to transfer amounts to the Stock Purchase option to be used by the trustee to purchase NB Bancorp common stock in connection with the stock offering, you may not change your election.
	Your election is irrevocable. You will, however, continue to have the ability to transfer amounts not directed towards the purchase of NB Bancorp common stock among all of the other investment funds on a daily basis.

 

Future Direction to Purchase and Sell Common Stock You will be able to purchase NB Bancorp common stock after the stock offering through the 401(k) Plan by investing your future contributions through the NB Bancorp, Inc. Stock Fund, provided, that no more than 100% of your future contributions (both employer and employee) may be invested in the NB Bancorp, Inc. Stock Fund. Additionally, after the stock offering, you will be able to transfer no more than 100% of your account balance to the NB Bancorp, Inc. Stock Fund.   After the stock offering, to the extent that shares are available, the trustees of the 401(k) Plan will acquire shares of NB Bancorp common stock at your election in open market transactions at the prevailing price, which may be less than or more than $10.00 per share. In addition, a brokerage commission of  $0.05 per share of stock purchased will be charged.   You may change your investment allocation on a daily basis.  However, please be advised that your ability to buy or sell NB Bancorp common stock within the 401(k) Plan largely depends upon the existence of an active market for the stock. If NB Bancorp common stock is illiquid (meaning there are a low number of buyers and sellers of the stock) on the date you elect to buy or sell NB Bancorp common stock within the 401(k) Plan, your election may not be immediately processed. As a result, the prevailing price for NB Bancorp, Inc. common stock may be less or more than its fair market value on the date of your election.   Special restrictions may apply to purchasing shares of NB Bancorp common stock by the participants who are subject to the provisions of Section 16(b) of the Securities Exchange Act of 1934, as amended, relating to the purchase and sale of securities by officers, directors and principal stockholders of NB Bancorp.   Please note that if you are an officer of the Needham Bank who is restricted by regulation from selling shares of NB Bancorp common stock acquired in the stock offering for one year, the NB Bancorp common stock that you purchased in the stock offering will not be tradable until the one-year trading restriction has lapsed.

 

S-6

 

Voting Rights of Common Stock You may direct the trustee as to how to vote your shares of NB Bancorp common stock held in the NB Bancorp, Inc. Stock Fund, if permitted by Needham Savings.  If the trustee does not receive your voting instructions, the trustee will be directed by Needham Bank to vote your shares in the same proportion as the voting instructions received from other participants related to their shares of NB Bancorp common stock held by the 401(k) Plan, provided that such vote is made in accordance with the Employee Retirement Income Security Act of 1974, as amended (“ERISA”). All voting instructions will be kept confidential.

 

DESCRIPTION OF THE 401(k) PLAN

Introduction

 

Needham Bank originally adopted the 401(k) Plan effective as of January 16, 1946. The 401(k) Plan was most recently amended and restated as of July 15, 2023. In connection with the mutual-to-stock conversion of NB Financial, MHC, Needham Bank and NB Bancorp desire to allow participants to purchase common stock of NB Bancorp in their accounts in the 401(k) Plan. The 401(k) Plan is a tax-qualified plan with a cash or deferred compensation feature established in accordance with the requirements under Section 401(a) and Section 401(k) of the Internal Revenue Code of 1986, as amended (the “Code”).

 

Needham Bank intends that the 401(k) Plan, in operation, will comply with the requirements under Section 401(a) and Section 401(k) of the Code. Needham Bank will adopt any amendments to the 401(k) Plan that may be necessary to ensure the continuing qualified status of the 401(k) Plan under the Code and applicable Treasury Regulations.

 

ERISA. The 401(k) Plan is an “individual account plan” other than a “money purchase pension plan” within the meaning of ERISA. As such, the 401(k) Plan is subject to all of the provisions of Title I (Protection of Employee Benefit Rights) and Title II (Amendments to the Code Relating to Retirement Plans) of ERISA, except to the funding requirements contained in Part 3 of Title I of ERISA, which by their terms do not apply to an individual account plan (other than a money purchase plan). The 401(k) Plan is not subject to Title IV (Plan Termination Insurance) of ERISA. The funding requirements contained in Title IV of ERISA are not applicable to participants or beneficiaries under the 401(k) Plan.

 

Reference to Full Text of Plan. The following portions of this prospectus supplement summarize certain provisions of the 401(k) Plan. They are not complete and are qualified in their entirety by the full text of the 401(k) Plan. Copies of the 401(k) Plan are available to all employees by filing a request with the 401(k) Plan Administrator c/o Needham Bank, Attn: Linda Farley, SVP, Human Resources/Learning & Development, Needham Bank, 1063 Great Plain Avenue, Needham, Massachusetts 02492; telephone number (781) 444-2100; email: lfarley@NeedhamBank.com.

 

Eligibility and Participation

 

As an employee of Needham Bank, you are eligible to become a participant in the 401(k) Plan on the entry date coinciding with or immediately following completion of one month of service and attainment of age 21. The entry dates under the 401(k) Plan are the first day of the month on or after you meet these requirements.

 

As of June 30, 2023, there were approximately 444 active and former employees with account balances in the 401(k) Plan.

 

Contributions under the Plan

 

Elective Deferrals. You may defer up to 75% of your compensation as of the date you become a participant in the 401(k) Plan, but may choose a different percentage or choose not to defer at all. You are automatically enrolled to defer 5% of your compensation.

 

S-7

 

You are permitted to defer up to 75% of your compensation, subject to certain restrictions imposed by the Code, and to have that amount contributed to the 401(k) Plan on your behalf. Your elective deferrals are subject to certain restrictions imposed by the Code, and for 2023, you may defer up to $22,500 and you may defer an additional $7,500 if you qualify for catch-up contributions as described in the next paragraph. The Compensation of each participant taken into account under the Plan is limited by the Code, and for 2023 the limit is $330,000 (this limit may change on an annual basis). Canceling or changing your contribution percentage can be accomplished by going to www.Principal.com.

 

Catch-up Contributions. If you have made the maximum amount of elective deferrals allowed by the 401(k) Plan or other legal limits and you have attained at least age 50 (or will reach age 50 prior to the end of the tax year, which is December 31), you are also eligible to make an additional catch-up contribution. In 2023, the maximum catch-up contribution is $7,500. You may authorize your employer to withhold a specified dollar amount of your compensation for this purpose.

 

Employer Contributions. Needham Bank currently makes a matching contribution of up to 8% of your contribution.

 

Limitations on Contributions

 

Contribution Limits. For the tax year beginning January 1, 2023, the amount of your elective deferrals may not exceed $22,500 per calendar year, or $30,000, if you are eligible to make catch-up contributions. Contributions in excess of this limit are known as excess deferrals. If you defer amounts in excess of this limitation, your gross income for federal income tax purposes will include the excess in the year of the deferral. In addition, unless the excess deferral is distributed before April 15 of the following year, it will be taxed again in the year distributed. Income on the excess deferral distributed by April 15 of the immediately succeeding year will be treated, for federal income tax purposes, as earned and received by you in the tax year in which the contribution is made.

 

The total amount of contributions that you make and any contribution your employer makes on your behalf to your account in one year is generally limited to the lesser of 100% of your compensation or $66,000 (for 2023), or if applicable, $73,500 (for 2023) including catch-up contributions.

 

Rollovers. You may make a rollover contribution of an eligible rollover distribution from any other qualified retirement plan or an individual retirement arrangement (IRA). These funds will be maintained in a separate rollover account in which you will have a nonforfeitable vested interest.

 

Benefits under the Plan

 

Vesting. At all times, you have a fully vested, nonforfeitable interest in the salary deferral portion of your account balance and you fully vest in matching contributions after three years of service under the 401(k) Plan.

 

Distribution at Termination of Employment. You will be entitled to receive a distribution of the vested amounts in your account when your employment terminates for any reason. Your benefit will be equal to the vested balance of your account. The Plan will make involuntary cash-out distributions of vested account balances in accordance with the Plan. If you are not a 5% or more owner of your employer, your required benefit commencement date is the April 1^st following the close of the year in which the later occurs: you attain age 72 ½ or you terminate employment.

 

Distribution after Death of Participant. In the event of your death, the value of your entire account will be payable to your beneficiary in accordance with the 401(k) Plan.

 

S-8

 

Investment of Contributions and Account Balances

 

All amounts credited to your accounts under the 401(k) Plan are held in the 401(k) Plan trust (the “Trust”), which is administered by the trustee of the 401(k) Plan. Prior to the effective date of the offering, you were provided the opportunity to direct the investments of your account into one of the investment options described below.

 

Equity Income Separate Account Z

Fidelity 500 Index Fund

Blue Chip Separate Account

MidCap Value I Separate Account

MidCap S&P 400 Index Separate Account

MidCap Growth Separate Account

SmallCap Value II Separate Account

DFA US Small Cap I Fund

Vanguard Explorer Admiral Fund

American Funds New World R6 Fund

MFS International Equity R6 Fund

Principal LifeTime Strategic Income CIT Tier I

Principal LifeTime 2015 CIT Tier I

Principal LifeTime 2020 CIT Tier I

Principal LifeTime 2025 CIT Tier I

Principal LifeTime 2030 CIT Tier I

Principal LifeTime 2035 CIT Tier I

Principal LifeTime 2040 CIT Tier I

Principal LifeTime 2045 CIT Tier I

Principal LifeTime 2050 CIT Tier I

Principal LifeTime 2055 CIT Tier I

Principal LifeTime 2060 CIT Tier I

Principal LifeTime 2065 CIT Tier I

Principal LifeTime 2070 CIT Tier I

PIMCO Income Institutional Fund

PGIM High Yield R6 Fund

Core Fixed Income Separate Account

AB Bond Inflation Strategy Z Fund

Principal Fixed Income Guaranteed Option

 

Performance History

 

The following table provides performance data with respect to the investment funds in the Plan:

	Average Annual Total Return (as of June 30, 2023)
Investment Option Name		1-Year		3-Year		5-Year		10-Year
Equity Income Separate Account Z		9.27	%	12.65	%	8.53	%	10.04	%
Fidelity 500 Index Fund		19.57	%	14.59	%	12.29	%	12.85	%
Blue Chip Separate Account		21.81	%	9.10	%	13.55	%	14.68	%
MidCap Value I Separate Account		12.26	%	17.63	%	9.26	%	9.84	%
MidCap S&P 400 Index Separate Account		17.56	%	15.37	%	7.71	%	10.12	%
MidCap Growth Separate Account		15.21	%	8.88	%	10.31	%	12.69	%
SmallCap Value II Separate Account		14.62	%	21.06	%	6.95	%	9.15	%
DFA US Small Cap I Fund		14.64	%	17.57	%	6.28	%	9.21	%
Vanguard Explorer Admiral Fund		16.75	%	10.66	%	8.66	%	11.06	%
American Funds New World R6 Fund		14.69	%	5.95	%	5.94	%	6.33	%
MFS International Equity R6 Fund		21.17	%	10.61	%	7.63	%	7.43	%
Principal LifeTime Strategic Income CIT Tier I		5.75	%	1.40	%	3.31	%	3.92	%
Principal LifeTime 2015 CIT Tier I		6.18	%	3.35	%	-		-
Principal LifeTime 2020 CIT Tier I		7.07	%	4.38	%	4.99	%	6.42	%
Principal LifeTime 2025 CIT Tier I		8.25	%	5.55	%	-		-

 

S-9

	Average Annual Total Return (as of June 30, 2023)
Investment Option Name	1-Year			3-Year			5-Year			10-Year
Principal LifeTime 2030 CIT Tier I		9.62	%		6.35	%		6.03	%		7.61	%
Principal LifeTime 2035 CIT Tier I		11.17	%		7.18	%		-			-
Principal LifeTime 2040 CIT Tier I		13.06	%		8.13	%		6.81	%		8.19	%
Principal LifeTime 2045 CIT Tier I		14.46	%		8.85	%		-			-
Principal LifeTime 2050 CIT Tier I		15.35	%		9.42	%		7.38	%		8.65	%
Principal LifeTime 2055 CIT Tier I		15.34	%		9.80	%		-			-
Principal LifeTime 2060 CIT Tier I		15.38	%		10.02	%		7.58	%		-
Principal LifeTime 2065 CIT Tier I		15.28	%		10.09	%		-			-
Principal LifeTime 2070 CIT Tier I		-			-			-			-
PIMCO Income Institutional Fund		5.34	%		1.85	%		2.60	%		4.24	%
PGIM High Yield R6 Fund		6.99	%		3.19	%		3.51	%		4.68	%
Core Fixed Income Separate Account		-0.18	%		-3.27	%		1.07	%		2.18	%
AB Bond Inflation Strategy Z Fund		-0.35	%		1.93	%		2.99	%		2.46	%
Principal Fixed Income Guaranteed Option		-			-			-			-

 

Description of the Investment Funds

 

Equity Income Separate Account Z. The investment seeks to provide current income and long-term growth of income and capital. Under normal circumstances, the fund invests at least 80% of its net assets, plus any borrowings for investment purposes, in dividend-paying equity securities at the time of purchase. It usually invests in equity securities of companies with large and medium market capitalizations. The fund invests in value equity securities, an investment strategy that emphasizes buying equity securities that appear to be undervalued.

 

Fidelity 500 Index Fund. The investment seeks to provide investment results that correspond to the total return performance of common stocks publicly traded in the United States. The fund normally invests at least 80% of assets in common stocks included in the S&P 500(R) Index, which broadly represents the performance of common stocks publicly traded in the United States. It lends securities to earn income.

 

Blue Chip Separate Account. The investment seeks long-term growth of capital. The fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of companies with large market capitalizations at the time of purchase that, in the fund's investment advisor's opinion, display characteristics of a "blue chip" company. The advisor tends to focus on securities of companies that show potential for growth of capital as well as an expectation for above average earnings. The fund invests in securities of foreign companies.

 

MidCap Value I Separate Account. The investment seeks long-term growth of capital. Under normal circumstances, the fund invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of companies with medium market capitalizations at the time of purchase. It invests in value equity securities, an investment strategy that emphasizes buying equity securities that appear to be undervalued. The fund also invests in real estate investment trusts.

 

MidCap S&P 400 Index Separate Account. The investment option normally invests the majority of assets in common stocks of companies that compose the S&P MidCap 400 Index. Management attempts to mirror the investment performance of the index by allocating assets in approximately the same weightings as the S&P MidCap 400 Index. Over the long-term, management seeks a very close correlation between the performance of the Separate Account before expenses and that of the S&P MidCap 400 Index.

 

MidCap Growth Separate Account. The investment option primarily invests in common stocks of medium capitalization companies with strong earnings growth potential. It normally invests the majority of assets in companies with market capitalizations similar to those companies in the Russell MidCap Growth Index. Management uses a bottom-up approach in selection of individual securities that it believes have an above average potential for earnings growth. It may invest up to 25% of assets in foreign securities.

 

S-10

 

SmallCap Value II Separate Account. The investment seeks long-term growth of capital. Under normal circumstances, the fund invests at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of companies with small market capitalizations at the time of purchase. It invests in value equity securities, an investment strategy that emphasizes buying equity securities that appear to be undervalued. The fund also invests in real estate investment trusts ("REITs").

 

DFA US Small Cap I Fund. The investment seeks long-term capital appreciation. The fund, using a market capitalization weighted approach, purchases a broad and diverse group of readily marketable securities of U.S. small cap companies. A company's market capitalization is the number of its shares outstanding times its price per share. Under a market capitalization weighted approach, companies with higher market capitalizations generally represent a larger proportion of the fund than companies with relatively lower market capitalizations.

 

Vanguard Explorer Admiral Fund. The investment seeks to provide long-term capital appreciation. The fund invests mainly in the stocks of small and mid-size companies. These companies tend to be unseasoned but are considered by the fund's advisors to have superior growth potential. Also, these companies often provide little or no dividend income. It uses multiple investment advisors.

 

American Funds New World R6 Fund. The investment seeks long-term capital appreciation. The fund invests primarily in common stocks of companies with significant exposure to countries with developing economies and/or markets. Under normal market conditions, the fund invests at least 35% of its assets in equity and debt securities of issuers primarily based in qualified countries that have developing economies and/or markets.

 

MFS International Equity R6 Fund. The investment seeks capital appreciation. The fund normally invests at least 80% of the fund's net assets in equity securities. It normally invests the fund's assets primarily in foreign securities, including emerging market securities. The fund normally invests the fund's assets across different industries, sectors, countries, and regions, but it may invest a significant percentage of the fund's assets in issuers in a single industry, sector, country, or region.

 

Principal LifeTime Strategic Income CIT Tier I. The investment seeks current income, and as a secondary objective, capital appreciation. The fund is a fund of funds and invests in underlying funds of Principal Funds, Inc. ("PFI"). Its underlying funds consist of domestic and foreign equity funds, fixed-income funds, real asset funds, and other funds that aim to offer diversification beyond traditional equity and fixed-income securities. Its asset allocation is designed for investors who are approximately 10 years beyond the normal retirement age of 65.

 

Principal LifeTime 2015 CIT Tier I. This CIT seeks total return consisting of long-term growth of capital and current income. The CIT invests in open-ended mutual funds, insurance company separate accounts, and collective trust funds, according to an asset allocation strategy designed for investors having an investment time horizon comparable to that of the CIT. It allocates the assets more conservatively over time.

 

Principal LifeTime 2020 CIT Tier I. This CIT seeks total return consisting of long-term growth of capital and current income. The CIT invests in open-ended mutual funds, insurance company separate accounts, and collective trust funds, according to an asset allocation strategy designed for investors having an investment time horizon comparable to that of the CIT. It allocates the assets more conservatively over time.

 

Principal LifeTime 2025 CIT Tier I. This CIT seeks total return consisting of long-term growth of capital and current income. The CIT invests in open-ended mutual funds, insurance company separate accounts, and collective trust funds, according to an asset allocation strategy designed for investors having an investment time horizon comparable to that of the CIT. It allocates the assets more conservatively over time.

 

Principal LifeTime 2030 CIT Tier I. This CIT seeks total return consisting of long-term growth of capital and current income. The CIT invests in open-ended mutual funds, insurance company separate accounts, and collective trust funds, according to an asset allocation strategy designed for investors having an investment time horizon comparable to that of the CIT. It allocates the assets more conservatively over time.

 

S-11

 

Principal LifeTime 2035 CIT Tier I. This CIT seeks total return consisting of long-term growth of capital and current income. The CIT invests in open-ended mutual funds, insurance company separate accounts, and collective trust funds, according to an asset allocation strategy designed for investors having an investment time horizon comparable to that of the CIT. It allocates the assets more conservatively over time.

 

Principal LifeTime 2040 CIT Tier I. This CIT seeks total return consisting of long-term growth of capital and current income. The CIT invests in open-ended mutual funds, insurance company separate accounts, and collective trust funds, according to an asset allocation strategy designed for investors having an investment time horizon comparable to that of the CIT. It allocates the assets more conservatively over time.

 

Principal LifeTime 2045 CIT Tier I. This CIT seeks total return consisting of long-term growth of capital and current income. The CIT invests in open-ended mutual funds, insurance company separate accounts, and collective trust funds, according to an asset allocation strategy designed for investors having an investment time horizon comparable to that of the CIT. It allocates the assets more conservatively over time.

 

Principal LifeTime 2050 CIT Tier I. This CIT seeks total return consisting of long-term growth of capital and current income. The CIT invests in open-ended mutual funds, insurance company separate accounts, and collective trust funds, according to an asset allocation strategy designed for investors having an investment time horizon comparable to that of the CIT. It allocates the assets more conservatively over time.

 

Principal LifeTime 2055 CIT Tier I. This CIT seeks total return consisting of long-term growth of capital and current income. The CIT invests in open-ended mutual funds, insurance company separate accounts, and collective trust funds, according to an asset allocation strategy designed for investors having an investment time horizon comparable to that of the CIT. It allocates the assets more conservatively over time.

 

Principal LifeTime 2060 CIT Tier I. This CIT seeks total return consisting of long-term growth of capital and current income. The CIT invests in open-ended mutual funds, insurance company separate accounts, and collective trust funds, according to an asset allocation strategy designed for investors having an investment time horizon comparable to that of the CIT. It allocates the assets more conservatively over time.

 

Principal LifeTime 2065 CIT Tier I. This CIT seeks total return consisting of long-term growth of capital and current income. The CIT invests in open-ended mutual funds, insurance company separate accounts, and collective trust funds, according to an asset allocation strategy designed for investors having an investment time horizon comparable to that of the CIT. It allocates the assets more conservatively over time.

 

Principal LifeTime 2070 CIT Tier I. This CIT seeks total return consisting of long-term growth of capital and current income. The CIT invests in open-ended mutual funds, insurance company separate accounts, and collective trust funds, according to an asset allocation strategy designed for investors having an investment time horizon comparable to that of the CIT. It allocates the assets more conservatively over time.

 

PIMCO Income Institutional Fund. The investment seeks to maximize current income; long-term capital appreciation is a secondary objective. The fund invests at least 65%of its total assets in a multi-sector portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. It may invest up to 50% of its total assets in high yield securities rated below investment grade by Moody's, S&P or Fitch, or if unrated, as determined by PIMCO.

 

PGIM High Yield R6 Fund. The investment seeks to maximize current income; and capital appreciation is a secondary objective. The fund normally invests at least 80% of its investable assets in a diversified portfolio of high yield fixed-income instruments rated Ba or lower by Moody's Investors Service ("Moody's") or BB or lower by S&P Global Ratings ("S&P"), and instruments either comparably rated by another nationally recognized statistical rating organization ("NRSRO"), or considered to be of comparable quality, that is, junk bonds.

 

Core Fixed Income Separate Account. The investment seeks to provide a high level of current income consistent with preservation of capital. The fund invests primarily in a diversified pool of investment-grade fixed-income securities, including corporate securities, U.S. government securities, asset-backed securities and mortgage-backed securities. It maintains an average portfolio duration that is within 25% of the duration of the Bloomberg U.S. Aggregate Bond Index.

 

S-12

 

AB Bond Inflation Strategy Z Fund. The investment seeks to maximize real return without assuming what the Adviser considers to be undue risk. The fund pursues its objective by investing principally in inflation-indexed securities (such as Treasury Inflation-Protected Securities ("TIPS") or inflation-indexed securities from issuers other than the U.S. Treasury) or by gaining inflation protection through derivatives transactions, such as inflation (CPI) swaps or total return swaps linked to TIPS. Under normal circumstances, it invests at least 80% of its net assets in fixed-income securities.

 

Principal Fixed Income Guaranteed Option. This group annuity contract provides an interest rate guaranteed for a set period of time by the Principal Life Insurance Company® (Principal Life). It is backed by the multi-billion-dollar general account of Principal Life, which invests in corporate bonds, asset-backed securities, commercial real-estate mortgages, government bonds, and short-term cash equivalents. However, money allocated to Principal® Fixed Income Guaranteed Option (PFIGO) does not entitle you to participate in the investment experience or performance of the general account. The composite crediting rate (crediting rate) applied to accounts is a weighted average of underlying guarantees provided in the contract. Each underlying guarantee has a final maturity date determined when the guarantee is established. That date can range between 2 and 10 years from the date the guarantee is established. The Term column below provides the targeted average maturity of the underlying guarantees. The crediting rate resets every 6 months based on the changing weighted average of the underlying guarantees and is announced in advance for the upcoming period. The crediting rate is an effective annual rate and is displayed below net of the Rate Level Service Fee. The crediting rate, before fees, is subject to a minimum guaranteed rate defined in the contract. When the crediting rate is reset, the minimum guaranteed rate is also recalculated in accordance with state insurance regulations which utilize U.S. Treasury rates. The formula is further outlined in the group annuity contract. The minimum guaranteed rate will range between 0.15% and 3%, depending on market conditions. Benefit payments to participants for plan benefit events, including retirement, termination of employment, disability, plan termination, death, loans, and withdrawals, as allowed by the plan, are made without any surrender charge. There are no restrictions or surrender charges on investment transfers initiated by a participant from PFIGO to non-competing investment options. If the retirement program provides access to PFIGO and Competing Investment Options, investment transfers directly to Competing Investment Options are not allowed. Competing Investment Options include other guaranteed investment options, or a stable value, money market, or other short term fixed income investment option with an average duration of less than two years. Indirect transfers from PFIGO to a Competing Investment Option will be subject to an Equity Wash. An Equity Wash requires that transfers be directed to a non-competing investment option for 90 days before a subsequent transfer can be made to Competing Investment Options. Termination of the Plan's Interest, Plan Sponsor's Interest (in the case of a nonqualified deferred compensation plan), or Participating Employer's Interest in the contract ("Party's Interest") is subject to either 12 months' advance notice (subject to additional contractual limitations) or a 5% surrender charge calculated using the 12-month average value of the Party's Interest in the contract, whichever the authorized plan representative chooses. PFIGO may make available higher crediting rates. If these are available and your authorized plan representative chooses to move a Plan's Interest or Plan Sponsor's Interest to a higher crediting rate, a charge of 1.50% of the Plan's Interest or Plan Sponsor's Interest applies. If there are multiple higher crediting rates available, the 1.50% charge applies to each higher crediting rate that your authorized plan representative elects. If the charge is directed by the authorized plan representative to be deducted, the actual charge applied to your account may be higher or lower than 1.50% depending on the plan's interest at the time the authorized plan representative chose to move to a higher crediting rate and the value of your account at the time of the movement. For more information, call the automated phone system at 1-800-547-7754 or see the applicable fact sheet on principal.com.

 

An investment in any of the funds listed above is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. As with any mutual fund investment, there is always a risk that you may lose money on your investment in any of the funds listed above.

 

S-13

 

NB Bancorp, Inc. Stock Fund

 

In connection with the stock offering, the 401(k) Plan now offers the NB Bancorp, Inc. Stock Fund as an additional choice to the investment options described above. The NB Bancorp, Inc. Stock Fund invests primarily in the shares of common stock of NB Bancorp. In connection with the stock offering, you may, in the manner described earlier, direct the trustee to invest up to 100% of your 401(k) Plan account in the NB Bancorp, Inc. Stock Fund.

 

As of the date of this prospectus supplement, there is no established market for NB Bancorp common stock. Accordingly, there is no record of the historical performance of the NB Bancorp, Inc. Stock Fund. Performance of the NB Bancorp, Inc. Stock Fund depends on a number of factors, including the financial condition and profitability of NB Bancorp and Needham Bank and market conditions for shares of NB Bancorp common stock generally.

 

Investments in the NB Bancorp, Inc. Stock Fund involve special risks common to investments in the shares of common stock of NB Bancorp. In making a decision to invest a part of your account balance in the NB Bancorp, Inc. Stock Fund, you should carefully consider the information set forth on page S-16 of this prospectus supplement under “Notice of Your Rights Concerning Employer Securities – The Importance of Diversifying Your Retirement Savings.”

 

For a discussion of material risks you should consider, see “Risk Factors” beginning on page 18 of the attached prospectus and the section of this prospectus supplement called “Notice of Your Rights Concerning Employer Securities” below.

 

Withdrawals from the Plan

 

Applicable federal law requires the Plan to impose substantial restrictions on the right of a 401(k) Plan participant to withdraw amounts held for his or her benefit under the 401(k) Plan prior to the participant’s termination of employment with Needham Bank. A substantial federal tax penalty may also be imposed on withdrawals made prior to the participant’s attainment of age 59 ½, regardless of whether the withdrawal occurs during his or her employment with Needham Bank or after termination of employment.

 

Withdrawal from your Account prior to Retirement. Once you have attained age 59 ½, you may request distribution of all or part of the amounts credited to your accounts attributable to elective deferrals, nonelective contributions and matching contributions.

 

Hardship Withdrawals. If you incur a financial hardship, you may request a withdrawal from the portion of your account attributable to your pre-tax and after-tax elective deferrals.

 

Rollover Contributions. You may withdraw amounts you contributed to the 401(k) Plan as a rollover contribution at any time.

 

Loan. You may request a loan from your account pursuant to the procedures established in the 401(k) Plan.

 

Administration of the Plan

 

The Trustee. The trustee of the Plan is Principal Trust Company. Principal Trust Company serves as trustee for all the investments funds under the Plan, except that Joseph P. Campanelli, Salvatore Rinaldi and Linda Farley will serve as trustees of the NB Bancorp, Inc. Stock Fund only during the stock offering period.

 

Plan Administrator. Pursuant to the terms of the Plan, the Plan is administered by the Plan administrator. The address of the Plan administrator is Needham Bank, 1063 Great Plain Avenue, 220 West Union Avenue, Needham, Massachusetts 02492. The Plan administrator is responsible for the administration of the Plan, interpretation of the provisions of the Plan, prescribing procedures for filing applications for benefits, preparation and distribution of information explaining the Plan, maintenance of plan records, books of account and all other data necessary for the proper administration of the Plan, preparation and filing of all returns and reports relating to the Plan which are required to be filed with the U.S. Department of Labor and the Internal Revenue Service, and for all disclosures required to be made to participants, beneficiaries and others under Sections 104 and 105 of ERISA.

 

S-14

 

Reports to Plan Participants. The 401(k) Plan administrator will furnish you a statement at least quarterly showing the balance in your account as of the end of that period, the amount of contributions allocated to your account for that period, and any adjustments to your account to reflect earnings or losses (if any). In addition, you can go on-line to principal.com or call 1-(800) 547-7754 at any time to review your account balances.

 

Amendment and Termination

 

It is the intention of Needham Bank to continue the 401(k) Plan indefinitely. Nevertheless, Needham Bank may terminate the 401(k) Plan at any time. If the 401(k) Plan is terminated in whole or in part, then regardless of other provisions in the 401(k) Plan, you will have a fully vested interest in your accounts. Needham Bank reserves the right to make any amendment or amendments to the 401(k) Plan which do not cause any part of the trust to be used for, or diverted to, any purpose other than the exclusive benefit of participants or their beneficiaries; provided, however, that Needham Bank may make any amendment it determines necessary or desirable, with or without retroactive effect, to comply with ERISA.

 

Merger, Consolidation or Transfer

 

In the event of the merger or consolidation of the 401(k) Plan with another plan, or the transfer of the trust assets to another plan, the 401(k) Plan requires that you would receive a benefit immediately after the merger, consolidation or transfer which is equal to or greater than the benefit you would have been entitled to receive immediately before the merger, consolidation or transfer.

 

Federal Income Tax Consequences

 

The following is a brief summary of the material federal income tax aspects of the 401(k) Plan. You should not rely on this summary as a complete or definitive description of the material federal income tax consequences relating to the 401(k) Plan. Statutory provisions change, as do their interpretations, and their application may vary in individual circumstances. Finally, the consequences under applicable state and local income tax laws may not be the same as under the federal income tax laws. Please consult your tax advisor with respect to any distribution from the 401(k) Plan and transactions involving the 401(k) Plan.

 

As a “tax-qualified retirement plan,” the Code affords the 401(k) Plan special tax treatment, including:

 

(1)        the sponsoring employer is allowed an immediate tax deduction for the amount contributed to the Plan each year;

 

(2)        participants pay no current income tax on amounts contributed by the employer on their behalf; and

 

(3)        earnings of the 401(k) Plan are tax-deferred, thereby permitting the tax-free accumulation of income and gains on investments.

 

Needham Bank will administer the 401(k) Plan to comply with the requirements of the Code as of the applicable effective date of any change in the law.

 

Lump-Sum Distribution. A distribution from the 401(k) Plan to a participant or the beneficiary of a participant will qualify as a lump-sum distribution if it is made within one taxable year, on account of the participant’s death, disability or separation from service, or after the participant attains age 59 ½, and consists of the balance credited to participants under the 401(k) Plan and all other profit sharing plans (and in some cases all other stock bonus plans), if any, maintained by Needham Bank. The portion of any lump-sum distribution required to be included in your taxable income for federal income tax purposes consists of the entire amount of the lump-sum distribution, less the amount of after-tax contributions, if any, you have made to this 401(k) Plan and any other profit sharing plans maintained by Needham Bank, which is included in the distribution.

 

S-15

 

NB Bancorp, Inc. Common Stock Included in Lump-Sum Distribution. If a lump-sum distribution includes NB Bancorp common stock, the distribution generally will be taxed in the manner described above, except that the total taxable amount may be reduced by the amount of any net unrealized appreciation with respect to NB Bancorp common stock, that is, the excess of the value of NB Bancorp common stock at the time of the distribution over its cost or other basis of the securities to the trust. The tax basis of NB Bancorp common stock, for purposes of computing gain or loss on its subsequent sale, equals the value of NB Bancorp common stock at the time of distribution, less the amount of net unrealized appreciation. Any gain on a subsequent sale or other taxable disposition of NB Bancorp common stock, to the extent of the amount of net unrealized appreciation at the time of distribution, will constitute long-term capital gain, regardless of the holding period of NB Bancorp common stock. Any gain on a subsequent sale or other taxable disposition of NB Bancorp common stock, in excess of the amount of net unrealized appreciation at the time of distribution, will be considered long-term capital gain. The recipient of a distribution may elect to include the amount of any net unrealized appreciation in the total taxable amount of the distribution, to the extent allowed by regulations to be issued by the Internal Revenue Service.

 

Distributions: Rollovers and Direct Transfers to Another Qualified Plan or to an IRA. You may roll over virtually all distributions from the 401(k) Plan to another qualified plan or to an individual retirement account (IRA) in accordance with the terms of the other plan or account.

 

Notice of Your Rights Concerning Employer Securities

 

There has been an important change in Federal law that provides specific rights concerning investments in employer securities, such as NB Bancorp common stock. Because you may in the future have investments in NB Bancorp, Inc. Stock Fund under the Plan, you should take the time to read the following information carefully.

 

Your Rights Concerning Employer Securities. The 401(k) Plan must allow you to elect to move any portion of your account that is invested in the NB Bancorp, Inc. Stock Fund from that investment into other investment alternatives under the 401(k) Plan. You may contact the 401(k) Plan Administrator shown above for specific information regarding this new right, including how to make this election. In deciding whether to exercise this right, you will want to give careful consideration to the information below that describes the importance of diversification. All of the investment options under the Plan are available to you if you decide to diversify out of the NB Bancorp, Inc. Stock Fund.

 

The Importance of Diversifying Your Retirement Savings. To help achieve long-term retirement security, you should give careful consideration to the benefits of a well-balanced and diversified investment portfolio. Spreading your assets among different types of investments can help you achieve a favorable rate of return, while minimizing your overall risk of losing money. This is because market or other economic conditions that cause one category of assets, or one particular security, to perform very well often cause another asset category, or another particular security, to perform poorly. If you invest more than 20% of your retirement savings in any one company or industry, your savings may not be properly diversified. Although diversification is not a guarantee against loss, it is an effective strategy to help you manage investment risk.

 

In deciding how to invest your retirement savings, you should take into account all of your assets, including any retirement savings outside of the Plan. No single approach is right for everyone because, among other factors, individuals have different financial goals, different time horizons for meeting their goals, and different tolerance for risk. Therefore, you should carefully consider the rights described here and how these rights affect the amount of money that you invest in NB Bancorp common stock through the 401(k) Plan.

 

It is also important to periodically review your investment portfolio, your investment objectives, and the investment options under the 401(k) Plan to help ensure that your retirement savings will meet your retirement goals.

 

S-16

 

Additional ERISA Considerations

 

As noted above, the 401(k) Plan is subject to certain provisions of ERISA, including special provisions relating to control over the 401(k) Plan’s assets by participants and beneficiaries. The 401(k) Plan’s feature that allows you to direct the investment of your account balances is intended to satisfy the requirements of Section 404(c) of ERISA relating to control over plan assets by a participant or beneficiary. The effect of this is two-fold. First, you will not be deemed a “fiduciary” because of your exercise of investment discretion. Second, no person who otherwise is a fiduciary, such as Needham Bank, the 401(k) Plan Administrator, or the 401(k) Plan’s trustee is liable under the fiduciary responsibility provision of ERISA for any loss which results from your exercise of control over the assets in your Plan account.

 

Because you will be entitled to invest all or a portion of your account balance in the Plan in NB Bancorp common stock, the regulations under Section 404(c) of ERISA require that the 401(k) Plan establish procedures that ensure the confidentiality of your decision to purchase, hold, or sell employer securities, except to the extent that disclosure of such information is necessary to comply with federal or state laws not preempted by ERISA. These regulations also require that your exercise of voting and similar rights with respect to the common stock be conducted in a way that ensures the confidentiality of your exercise of these rights.

 

Securities and Exchange Commission Reporting and Short-Swing Profit Liability

 

Section 16 of the Securities Exchange Act of 1934, as amended, imposes reporting and liability requirements on officers, directors, and persons beneficially owning more than 10% of public companies such as NB Bancorp. Section 16(a) of the Securities Exchange Act of 1934 requires the filing of reports of beneficial ownership. Within 10 days of becoming an officer, director or person beneficially owning more than 10% of the shares of NB Bancorp, the individual must fill out a Form 3 reporting initial beneficial ownership and file it with the Securities and Exchange Commission. Changes in beneficial ownership, such as purchases, sales and gifts generally must be reported periodically, either on a Form 4 within two business days after the change occurs, or annually on a Form 5 within 45 days after the close of NB Bancorp’s fiscal year. Discretionary transactions in and beneficial ownership of the common stock through the NB Bancorp, Inc. Stock Fund of the Plan by officers and persons beneficially owning more than 10% of the common stock of NB Bancorp generally must be reported to the Securities and Exchange Commission by such individuals.

 

In addition to the reporting requirements described above, Section 16(b) of the Securities Exchange Act of 1934, as amended, provides for the recovery by NB Bancorp of profits realized by an officer, director or any person beneficially owning more than 10% of NB Bancorp’s common stock resulting from non-exempt purchases and sales of NB Bancorp common stock within any six-month period.

 

The Securities and Exchange Commission has adopted rules that provide exemptions from the profit recovery provisions of Section 16(b) for all transactions in employer securities within an employee benefit plan, provided certain requirements are met. These requirements generally involve restrictions upon the timing of elections to acquire or dispose of employer securities for the accounts of Section 16(b) persons.

 

Except for distributions of common stock due to death, disability, retirement, termination of employment or under a qualified domestic relations order, persons affected by Section 16(b) are required to hold shares of common stock distributed from the Plan for six months following such distribution and are prohibited from directing additional purchases within the NB Bancorp, Inc. Stock Fund for six months after receiving such a distribution.

 

Financial Information Regarding Plan Assets

 

Financial information representing the net assets available for 401(k) Plan benefits and the change in net assets available for 401(k) Plan benefits is available upon written request to the Plan Administrator at the address shown above.

 

LEGAL OPINION

 

The validity of the issuance of the common stock has been passed upon by Luse Gorman, PC, Washington, D.C., which firm acted as special counsel to NB Bancorp in connection with NB Bancorp’s stock offering.

 

S-17

SUBSCRIPTION AND COMMUNITY

OFFERING PROSPECTUS

NB Bancorp, Inc.

(Proposed Holding Company for Needham Bank)

Up to 35,650,000 shares of Common Stock

(Subject to increase to up to 40,997,500 shares)

NB Bancorp, Inc., a newly formed Maryland corporation, and the proposed holding company for Needham Bank, is offering shares of common stock for sale in connection with the conversion of NB Financial, MHC, from a mutual holding company to a stock holding company form of organization. There is currently no public market for the shares of our common stock. We expect that upon conclusion of the offering our common stock will be listed on the Nasdaq Capital Market under the symbol “NBBK.” We are an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012 and, as such, we have elected to comply with certain reduced public company reporting requirements for this prospectus and future filings.

We are offering up to 35,650,000 shares of common stock for sale. We must sell a minimum of 26,350,000 shares in order to complete the offering. We may sell up to 40,997,500 shares of common stock because of demand for the shares or changes in market conditions without resoliciting subscribers.

We are offering the shares of common stock in a subscription offering to eligible depositors of Needham Bank. Employees, officers, directors and corporators of NB Financial, MHC, NB Financial, Inc, Needham Bank and NB Bancorp, Inc. also have rights to purchase shares in the subscription offering, subject to the priority rights of Needham Bank’s eligible depositors and its tax-qualified employee benefit plans. Shares of common stock not purchased in the subscription offering may be offered for sale to the general public in a community offering, with a preference given to residents of the communities served by Needham Bank. Any shares of common stock not purchased in the subscription offering or community offering may be offered for sale in a syndicated community offering to be managed by Piper Sandler & Co. Piper Sandler & Co. will assist us in selling the shares in the subscription offering and any community or syndicated community offering on a best efforts basis, but is not required to purchase any shares of the common stock that are being offered for sale in those offerings. In addition to the shares that we will sell in the offering, we will also contribute to a charitable foundation that we are establishing in connection with the conversion, $2.0 million of cash and a number of shares of our common stock equal to 4% of the shares that will be outstanding immediately after this contribution.

The minimum purchase order is 25 shares. All shares of common stock are being offered for sale at a price of $10.00 per share. Purchasers will not pay a commission to purchase shares of common stock in the offering. Stock orders must be received by us before 4:00 p.m., Eastern Time, on November 14, 2023. We may extend this expiration date without notice to you until December 29, 2023, unless we receive regulatory approval to extend the offering to a later date, which may not be beyond June 7, 2025. Once submitted, orders are irrevocable unless the offering is terminated or is extended beyond December 29, 2023, or the number of shares of common stock to be sold is increased to more than 40,997,500 shares or decreased to fewer than 26,350,000 shares. If the offering is extended past December 29, 2023, or the number of shares to be sold is increased to more than 40,997,500 shares or decreased to less than 26,350,000 shares, we will resolicit subscribers, giving them an opportunity to change or cancel their orders. Funds received during the offering will be held in a segregated account at Needham Bank and will earn interest at 0.05% until completion or termination of the offering.

We expect that our directors and executive officers, together with their associates, will subscribe for approximately 762,500 shares of our common stock.

This investment involves a degree of risk, including the possible loss of your investment.

Please read “Risk Factors” beginning on page 18.

OFFERING SUMMARY

Price: $10.00 per Share

	Minimum		Midpoint		Maximum		Adjusted Maximum
Number of shares		26,350,000		31,000,000		35,650,000		40,997,500
Gross offering proceeds	$	263,500,000	$	310,000,000	$	356,500,000	$	409,975,000
Estimated offering expenses, excluding selling agent fees and expenses  (1) (2)	$	2,830,000	$	2,830,000	$	2,830,000	$	2,830,000
Selling agent fees and expenses (1)	$	3,402,875	$	3,978,313	$	4,553,750	$	5,215,503
Estimated net proceeds	$	257,267,125	$	303,191,687	$	349,116,250	$	401,929,497
Estimated net proceeds per share (1)	$	9.76	$	9.78	$	9.79	$	9.80

1.	See “The Conversion and Plan of Distribution – Marketing and Distribution; Compensation” for a discussion of Piper Sandler & Co.’s compensation for this offering and the compensation to be received by Piper Sandler & Co. and the other broker-dealers that may participate in the syndicated community offering.
2.	Excludes records agent fees and expenses payable to Piper Sandler & Co., which are included in estimated offering expenses. See “The Conversion and Plan of Distribution – Marketing and Distribution; Compensation.”

These securities are not deposits or savings accounts and are not insured or guaranteed by the Federal Deposit Insurance Corporation, any other government agency, or the Massachusetts Depositors Insurance Fund.

None of the Securities and Exchange Commission, the Board of Governors of the Federal Reserve System, the Massachusetts Commissioner of Banks, the Federal Deposit Insurance Corporation, nor any state securities regulator has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

For assistance, please call the Stock Information Center, toll free, at (844) 305-2265.

Piper Sandler

The date of this prospectus is [prospectus date].

 

TABLE OF CONTENTS

	Page
SUMMARY	1
RISK FACTORS	18
SELECTED FINANCIAL AND OTHER DATA	43
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS	45
HOW WE INTEND TO USE THE PROCEEDS FROM THE OFFERING	47
OUR POLICY REGARDING DIVIDENDS	48
MARKET FOR THE COMMON STOCK	49
HISTORICAL AND PRO FORMA REGULATORY CAPITAL COMPLIANCE	50
CAPITALIZATION	51
PRO FORMA DATA	52
MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS	58
BUSINESS OF NB BANCORP	78
BUSINESS OF NEEDHAM BANK	78
SUPERVISION AND REGULATION	104
TAXATION	117
MANAGEMENT OF NB BANCORP	118
SUBSCRIPTIONS BY DIRECTORS AND EXECUTIVE OFFICERS	134
THE CONVERSION AND PLAN OF DISTRIBUTION	135
NEEDHAM BANK CHARITABLE FOUNDATION	159
RESTRICTIONS ON ACQUISITION OF NB BANCORP	163
DESCRIPTION OF CAPITAL STOCK	168
TRANSFER AGENT	170
EXPERTS	170
CHANGE IN AUDITOR	170
LEGAL AND TAX MATTERS	171
WHERE YOU CAN FIND ADDITIONAL INFORMATION	171
Index to Consolidated Financial Statements	F-1

SUMMARY

The following summary explains the significant aspects of NB Financial, MHC’s mutual-to-stock conversion and the related offering of NB Bancorp, Inc. common stock. It may not contain all of the information that is important to you. For additional information before making an investment decision, you should read this entire document carefully, including the consolidated financial statements and the notes to the financial statements, and the section entitled “Risk Factors.”

In this prospectus, the terms “we,” “our,” and “us” refer to NB Bancorp, Inc., Needham Bank, NB Financial, MHC and NB Financial, Inc. unless the context indicates another meaning. In addition, we sometimes refer to NB Bancorp, Inc. as “NB Bancorp,” and to Needham Bank as the “Bank.”

NB Bancorp, Inc.

NB Bancorp is a newly formed Maryland corporation that will own all of the outstanding shares of common stock of Needham Bank upon completion of the conversion and the offering. NB Bancorp has not engaged in any business to date. Our executive offices are located at 1063 Great Plain Avenue, Needham, Massachusetts 02492. Our telephone number at this address is (781) 444-2100.

Needham Bank

Needham Bank is a Massachusetts-chartered cooperative bank headquartered in Needham, Massachusetts. Needham Bank was organized in 1892 and has operated continuously in Needham, Massachusetts, since this time. Our primary market area is the Greater Boston metropolitan area and surrounding communities, including eastern Connecticut, southern New Hampshire and Rhode Island. Our headquarters are located in Needham, Massachusetts, which is approximately 17 miles southwest of Boston’s financial district, and we have branch locations in Wellesley, Westwood, Dedham, Medfield, Medford, Dover, Ashland, Millis, Natick and Boston (Mission Hill), Massachusetts.

Our business consists primarily of taking deposits from the general public and investing those deposits, together with funds generated from operations, in commercial real estate and multifamily loans, one- to four-family residential real estate loans, construction and land development loans, commercial and industrial loans and consumer loans. To a lesser extent, we also originate home equity loans and lines of credit. At June 30, 2023, $1.23 billion, or 34.9%, of our total loan portfolio was comprised of commercial real estate and multifamily loans, and $1.01 billion, or 28.7%, of our total loan portfolio was comprised of one- to four-family residential real estate loans. We also invest in securities, consisting primarily of U.S. Treasury and federal agency securities, municipal bonds and corporate bonds. We offer a variety of deposit accounts, including certificate of deposit accounts, IRAs, money market accounts, savings accounts, demand deposit accounts and interest-bearing and noninterest-bearing checking accounts. We historically have utilized advances from the Federal Home Loan Bank of Boston (the “FHLB”) to fund our operations and we had $337.6 million of FHLB advances outstanding at June 30, 2023. Additionally, in recent years, we have also accepted brokered deposits as a non-retail funding source to fund our operations and we had $253.6 million of brokered deposits at June 30, 2023.

Needham Bank is subject to regulation, supervision and examination by the Massachusetts Commissioner of Banks, or the “Commissioner,” under Massachusetts law, and the Board of Governors of the Federal Reserve System, or the “Federal Reserve Board,” as its primary federal regulator. It is also regulated by Federal Deposit Insurance Corporation, or the “FDIC,” as its primary insurer of its deposits.

Our executive offices are located at 1063 Great Plain Avenue, Needham, Massachusetts 02492. Our telephone number at this address is (781) 444-2100. Our website address is www.needhambank.com. Information on our website is not incorporated into this prospectus and should not be considered part of this prospectus.

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Business Strategy

As one of the largest community banks in the Greater Boston metropolitan area, and throughout New England, we believe that our reputation for providing personalized customer service is our strongest asset and our most effective business strategy to continue to grow and be a profitable bank.

In recent years, we have focused on building an experienced management team and diversifying and enhancing our operating and business strategy. In January 2017, we hired Joseph Campanelli as our Chief Executive Officer, and in April 2017, we hired Salvatore Rinaldi, our Chief Operating Officer. Messrs. Campanelli and Rinaldi each have more than 40 years of banking experience, and have worked together for over 40 years at other financial institutions prior to joining Needham Bank. Under their leadership, the Bank has implemented an intentional and structured growth plan to enable the Bank to grow its balance sheet and diversify its operations and offer a personalized banking experience to individuals and businesses while seeking to address the risks inherent with such growth.

Since 2020, the Bank added approximately 102 full time employees, including approximately 23 employees in connection with the April 2022 acquisition of a cannabis banking business from another financial institution. Consistent with our strategy to continue to service individuals and small businesses in our market area, while also competing for larger business customers, the Bank has invested heavily in infrastructure, upgraded technology solutions and offerings, and compliance and risk management.

In May 2023, we added four new board members, and in July 2023 added a fifth new director, each of whom individually, and together as a group, we believe bring a level of business acumen and sophistication that matches our growth strategy.

The proceeds from the stock offering will enable us to continue to implement our prudent growth strategy, and we plan to employ the following strategies to maximize profitability:

· Continue to grow our commercial real estate and multifamily loan portfolio. In recent years, we have increased our commercial real estate and multifamily loan portfolio consistent with safe and sound underwriting practices. This has had the benefit of increasing the yield on our loan portfolio while reducing the average term to repricing of our loans. At June 30, 2023, our commercial real estate and multifamily loan portfolio totaled $1.23 billion, or 34.9%, of our total loan portfolio, compared with $642.7 million, or 30.6% of total loans, at December 31, 2021. We intend to continue to compete for more and larger loan relationships, primarily to experienced builders, developers and investors in our market area.

· Continue to diversify our commercial and industrial loan portfolio. We have diversified our commercial and industrial loan portfolio into three divisions, which we refer to as Small Business, Middle Market and Structured Finance. The Small Business Lending division generally focuses on loans under Small Business Administration, or “SBA,” programs of up to $5 million and traditional non-small SBA commercial business loans generally up to $2 million, and our Middle Market lending division generally focuses on loans from $2 million to $10 million for a variety of operating businesses, nearly all of which are to borrowers in our primary market area. Our Structured Finance division seeks to service the banking needs of larger business customers, which to date have primarily been in the cannabis, wind and solar industries. We believe that our industry-specific knowledge about the banking needs of these industries gives us a competitive advantage to service these customers. We intend to continue to emphasize growth in each of these divisions of our commercial and industrial lending.

2

· Continue our historical emphasis on residential mortgage lending, including construction of single-family homes. Historically, we have emphasized residential mortgage lending, including for the construction of single-family homes, and at June 30, 2023, one- to four-family residential real estate loans totaled $1.01 billion, or 28.7% of our total loan portfolio. We intend to continue measured, efficient growth of these types of residential lending.

· Grow our consumer loan operations. We seek to continue our growth in consumer loan operations, and in 2022, we began purchasing a variety of consumer loans from a third-party originator. Largely as a result of these purchases, at June 30, 2023, consumer loans totaled $204.4 million, or 5.8% of our total loan portfolio, compared to $39.4 million, or 1.9% of our total loan portfolio, at December 31, 2021. We intend to continue to emphasize the growth in our consumer loan portfolio, either through ongoing purchases or originations. We believe that this loan diversification will allow us to continue to execute our business strategy of growing the Bank while addressing the inherent risks of community banking, including the risk of geographic concentrations in our loan portfolios. The diversification of our loan products allows us to address risk across a wider variety of borrowers and industries as well as the ongoing management of these portfolios to minimize our exposure to interest rate risk.

· Diversify our deposit gathering. Consistent with our strategy to grow core deposits, which we consider all deposits including certificates of deposits, other than brokered deposits, we have invested in a cash management suite of products and enhanced our online and mobile banking offerings, as well as fraud prevention and detection systems. We intend to continue to implement new technology as it is developed or improved. We view the growth of commercial and industrial lending, in each of our market segments, as an opportunity to increase our core deposits through our effort to capture the full banking relationship of these commercial customers.

Our Organizational Structure and the Proposed Conversion

In January 2020, Needham Bank completed a mutual holding company reorganization at which time Needham Bank became the wholly owned subsidiary of NB Financial, Inc., a Massachusetts corporation, which in turn became the wholly owned subsidiary of NB Financial, MHC, a Massachusetts-chartered mutual holding company. The following diagram shows our organizational structure as of June 30, 2023:

NB FINANCIAL, MHC (a Massachusetts mutual holding company)
	100% of common stock
NB FINANCIAL, INC. (a Massachusetts stock corporation)
	100% of common stock
NEEDHAM BANK (a Massachusetts stock cooperative bank)

3

After the conversion and offering are completed, we will be organized as a fully public stock holding company, as follows:

PUBLIC STOCKHOLDERS (including charitable foundation)
	100% of common stock
NB BANCORP, INC. (a Maryland stock corporation)
	100% of common stock
NEEDHAM BANK (a Massachusetts stock cooperative bank)

Reasons for the Conversion

We believe the stock form of organization will provide us with access to additional resources to expand the products and services we offer our customers. Management believes that the additional capital raised in the offering will enable us to take advantage of business opportunities that may not otherwise be available to us, while allowing us to retain our commitment to remaining an independent community bank. Our primary reasons for converting and raising additional capital through the offering are to:

· better position the Bank to remain an independent community bank by increasing our capital to enhance our financial strength;

· support future lending in an orderly and diligent manner, including, in particular, construction and land development lending, commercial and industrial lending, including small business lending, middle market commercial lending, and structured finance lending;

· enable us to compete for, originate and retain larger loans and maintain larger lending relationships, particularly loans and relationships in our local community, thereby allowing us to maintain a reputation as a locally managed community lender;

· continue to invest in new technologies and personnel that will enable us to expand and enhance our products and services;

· support our banking franchise as opportunities arise through targeted de novo branching and/or branch acquisitions;

· attract and retain qualified personnel by enabling us to establish stock-based benefit plans for management and employees that will give them an opportunity to share in our long-term success;

· enhance our community ties by providing customers and members of our community with the opportunity to acquire an ownership interest in NB Bancorp and Needham Bank; and

4

· establish a foundation to support charitable organizations operating in our local communities now and in the future and fund the foundation with shares of our common stock and cash.

As of June 30, 2023, Needham Bank was considered “well capitalized” for regulatory purposes and was not subject to a directive or a recommendation from any regulator to raise capital. The proceeds from the offering will further improve our capital position.

Terms of the Offering

We are offering between 26,350,000 shares and 35,650,000 shares of common stock to eligible depositors of Needham Bank and our tax qualified employee benefit plans, and, to the extent shares remain available, to members of our local community and the general public. The number of shares of common stock to be sold may be increased to up to 40,997,500 shares as a result of demand for the shares or changes in the market for financial institution stocks. Unless the number of shares of common stock to be offered is increased to greater than 40,997,500 shares or decreased to fewer than 26,350,000 shares, or the offering is extended beyond December 29, 2023, subscribers will not have the opportunity to change or cancel their stock orders once submitted.

The purchase price of each share of common stock to be issued in the offering (other than shares we are contributing to our charitable foundation) is $10.00. Investors will not be charged a commission to purchase shares of common stock in the offering.

Persons Who May Order Shares of Common Stock in the Offering

We are offering the shares of common stock in a subscription offering in the following descending order of priority:

· First, to depositors of Needham Bank with aggregate account balances of at least $50 as of the close of business on March 31, 2022.

· Second, to depositors of Needham Bank with aggregate account balances of at least $50 as of the close of business on June 9, 2023.

· Third, to Needham Bank’s tax-qualified employee benefit plans (including the ESOP we are establishing in connection with the conversion), which will receive, without payment therefor, nontransferable subscription rights to purchase in the aggregate up to 10% of the shares of common stock issued in the offering (including shares contributed to our charitable foundation). We expect our tax-qualified ESOP to purchase 8% of the shares of common stock issued in the offering (including shares contributed to our charitable foundation).

· Fourth, to employees, officers, directors and corporators of Needham Bank, NB Financial, MHC, NB Financial, Inc. and NB Bancorp who do not have a higher purchase priority.

Shares of common stock not purchased in the subscription offering may be offered for sale to the general public in a community offering, with a preference given to natural persons (including trusts of natural persons) residing in the following Massachusetts towns and cities: in Norfolk County, the following cities and towns: Brookline, Dedham, Dover, Franklin, Medfield, Millis, Needham, Norfolk, Norwood, Walpole, Wellesley and Westwood; in Middlesex County, the following cities and towns: Arlington, Ashland, Belmont, Cambridge, Everett, Framingham, Holliston, Hopkinton, Malden, Medford, Medway, Natick, Newton, Sherborn, Somerville, Waltham, Watertown, Wayland and Weston; in Worcester County, the following cities and towns: Milford; and in Suffolk County, the following cities and towns: Boston and Chelsea (which we refer to herein, collectively, as our “Local Community”). We also may offer for sale shares of common stock not purchased in the subscription offering or the community offering to the general public through a syndicated community offering, which will be managed by Piper Sandler & Co. We have the right to accept or reject, in our sole discretion, orders received in the community offering or syndicated community offering, and our interpretation of the terms and conditions of the plan of conversion will be final, subject to the authority of the Commissioner and the Federal Reserve Board. Any determination to accept or reject stock orders in the community offering or the syndicated community offering will be based on the facts and circumstances available to management at the time of the determination.

5

If we receive orders for more shares than we are offering, we may not be able to fully or partially fill your order. Shares will be allocated first to categories in the subscription offering. A detailed description of the subscription offering, the community offering and the syndicated community offering, as well as a discussion regarding allocation procedures, can be found in the section of this prospectus entitled “The Conversion and Plan of Distribution.”

How We Determined the Offering Range

The amount of common stock that we are offering is based on an independent appraisal of the estimated market value of NB Bancorp, assuming the offering is completed. RP Financial, LC., our independent appraiser, has estimated that, as of August 25, 2023, this market value (including cash and shares to be contributed to the charitable foundation) was $310.0 million. Based on applicable state and federal regulations, this market value forms the midpoint of a valuation range with a minimum of $263.5 million and a maximum of $356.5 million. Based on this valuation range and the $10.00 per share price, the number of shares of common stock being offered for sale by NB Bancorp ranges from 26,350,000 shares to 35,650,000 shares. The purchase price of $10.00 per share was selected primarily because it is the price most commonly used in mutual-to-stock conversions of financial institutions. RP Financial, LC. will update its appraisal before we complete the conversion and offering. If, as a result of demand for the shares or changes in market conditions, RP Financial, LC. determines that our estimated pro forma market value has increased, we may sell up to 40,997,500 shares without further notice to you. If our pro forma market value at the time we complete the conversion and offering is either below $263.5 million or above $410.0 million, then, after consulting with the Massachusetts Division of Banks and the Federal Reserve Board, we may: terminate the offering and promptly return all funds with interest; set a new offering range and give all subscribers the opportunity to place a new order; or take such other actions as may be permitted by our regulators.

RP Financial, LC. also considered that we intend to contribute to a charitable foundation that we are establishing $2.0 million in cash and a number of shares of our common stock equal to 4% of the shares that will be outstanding immediately after this contribution. The intended contribution of cash and shares of common stock to our charitable foundation has the effect of reducing our estimated pro forma valuation.

The appraisal is based in part on our financial condition and results of operations, the pro forma effect of the capital raised by the sale of shares of common stock in the offering, and an analysis of a peer group of ten publicly traded savings and loan and bank holding companies that RP Financial, LC. considered comparable to us. The appraisal peer group consists of the following companies, all of which are traded on the Nasdaq Stock Market.

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Company Name and Ticker Symbol	Exchange	Headquarters	Total assets as of June 30, 2023
			(in millions)
Northeast Community Bancorp, Inc. (NECB)	Nasdaq	White Plains, NY	$	1,616
ESSA Bancorp, Inc. (ESSA)	Nasdaq	Stroudsburg, PA	$	2,184
Blue Foundry Bancorp (BLFY)	Nasdaq	Rutherford, NJ	$	2,081
Western New England Bancorp, Inc. (WNEB)	Nasdaq	Westfield, MA	$	2,562
Hingham Institution for Savings (HIFS)	Nasdaq	Hingham, MA	$	4,311
HarborOne Bancorp, Inc. (HONE)	Nasdaq	Brockton, MA	$	5,659
Northfield Bancorp, Inc. (Staten Island, NY) (NFBK)	Nasdaq	Woodbridge, NJ	$	5,541
TrustCo Bank Corp NY (TRST)	Nasdaq	Glenville, NY	$	6,076
Kearny Financial Corp. (KRNY)	Nasdaq	Fairfield, NJ	$	8,065
Provident Financial Services, Inc. (PFS)	NYSE	Jersey City, NJ	$	14,030

The following table presents a summary of our selected pricing ratios (on a pro forma basis) as of and for the twelve months ended June 30, 2023 and for the peer group as of and for the twelve months ended June 30, 2023 (or the last twelve months for which data are available), with stock prices as of August 25, 2023, as reflected in the appraisal report. Compared to the average pricing of the peer group, our pro forma pricing ratios at the midpoint of the offering range indicated a premium of 12.8% on a price-to-earnings basis, a discount of 31.6% on a price-to-book value basis and a discount of 37.4% on a price-to-tangible book value basis.

	Price-to-earnings multiple(1)			Price-to-book value ratio			Price-to-tangible book value ratio
NB Bancorp (on a pro forma basis, assuming completion of the conversion)
Adjusted Maximum		12.41	X		60.13	%		60.24	%
Maximum		10.92	X		55.96	%		56.09	%
Midpoint		9.59	X		51.81	%		51.92	%
Minimum		8.24	X		47.10	%		47.21	%
Valuation of peer group companies, all of which are fully converted (on an historical basis)
Averages		8.50	X		75.78	%		82.93	%
Medians		7.95	X		74.85	%		83.78	%

(1) Price-to-earnings multiples calculated by RP Financial, LC. in the independent appraisal are based on an estimate of “core” or recurring earnings. These ratios are different than those presented in “Pro Forma Data.”

The independent appraisal does not indicate trading market value. Do not assume or expect that our valuation as indicated in the appraisal means that after the conversion and offering the shares of our common stock will trade at or above the $10.00 per share purchase price. Furthermore, the pricing ratios presented in the appraisal were used by RP Financial, LC. to estimate our pro forma appraised value for regulatory purposes and not to compare the relative value of shares of our common stock with the value of the capital stock of the peer group. The value of the capital stock of a particular company may be affected by a number of factors such as financial performance, asset size and market location.

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For a more complete discussion of the amount of common stock we are offering for sale and the independent appraisal, see “The Conversion and Plan of Distribution – Determination of Share Price and Number of Shares to be Issued.”

Limits on How Much Common Stock You May Purchase

The minimum number of shares of common stock that may be purchased is 25. Generally, no individual, or individuals exercising subscription rights through a single qualifying account held jointly, may purchase more than 80,000 shares ($800,000) of common stock. Additionally, if any of the following persons purchase shares of common stock, their purchases, in all categories of the offering, will be combined with your purchases and may not exceed 80,000 shares ($800,000):

· your spouse or any relative of you or your spouse living in your house, or who is a director or officer of NB Financial, MHC, NB Financial, Inc. or Needham Bank or any subsidiary of Needham Bank;

· most companies, trusts or other entities in which you are a trustee, have a substantial beneficial interest or hold a senior management position; or

· other persons who may be your associates or persons acting in concert with you.

See the detailed descriptions of “acting in concert” and “associate” in “The Conversion and Plan of Distribution – Limitations on Common Stock Purchases.”

Subject to regulatory approval, we may increase or decrease the purchase limitations at any time. Please see “The Conversion and Plan of Distribution – Limitations on Common Stock Purchases.”

How You May Purchase Shares of Common Stock in the Subscription Offering and the Community Offering

In the subscription offering and community offering, you may pay for your shares only by:

· personal check, bank check or money order made payable directly to NB Bancorp, Inc.;

· authorizing us to withdraw available funds from the types of Needham Bank deposit accounts identified on the stock order form; or

· cash.

Cash will be accepted only at Needham Bank’s main office and will be converted to a bank check. Please do not submit cash by mail.

Needham Bank is not permitted to lend funds to anyone for the purpose of purchasing shares of common stock in the offering. Additionally, you may not use a Needham Bank line of credit check or any type of third-party check to pay for shares of common stock. On the stock order form, you may not designate withdrawal from Needham Bank accounts with check-writing privileges; instead, please submit a check. If you request that we directly withdraw the funds from an account with check writing privileges, we reserve the right to interpret that as your authorization to treat those funds as if we had received a check for the designated amount, and we will immediately withdraw the amount from your checking account. Funds received in the subscription and community offerings and, if applicable, the syndicated community offering will be held in a segregated account at Needham Bank and will earn interest at 0.05% until completion or termination of the offering. You may not authorize direct withdrawal from a Needham Bank retirement account. See “ – Using Retirement Account Funds to Purchase Shares of Common Stock in the Subscription and Community Offerings.”

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In order to purchase shares of common stock in the subscription offering and community offering, you must submit a signed and completed original stock order form, together with full payment payable to NB Bancorp or authorization to withdraw funds from one or more of your Needham Bank deposit accounts. We will not be required to accept incomplete order forms, unsigned order forms, or orders submitted on photocopied or facsimiled order forms. We must receive all order forms before 4:00 p.m., Eastern Time, on November 14, 2023. Orders received after 4:00 p.m., Eastern Time, on November 14, 2023 will be rejected unless we extend this expiration date. You may submit your stock order form and payment by mail using the stock order reply envelope provided, by paying for overnight delivery to our Stock Information Center at the address noted on the stock order form or by hand-delivery to the drop box at Needham Bank’s office, located at 1063 Great Plain Avenue, Needham, Massachusetts. We will accept order forms only at this location. Please do not mail stock order forms to Needham Bank. Once submitted, your order will be irrevocable unless the offering is terminated or is extended beyond December 29, 2023, or the number of shares of common stock to be sold is increased to greater than 40,997,500 shares or decreased to fewer than 26,350,000 shares.

For a complete description of how to purchase shares in the offering, see “The Conversion and Plan of Distribution – Procedure for Purchasing Shares.”

Using Retirement Account Funds to Purchase Shares of Common Stock in the Subscription and Community Offerings

You may be able to subscribe for shares of common stock using funds in your IRA or other retirement account. If you wish to use some or all of the funds in your Needham Bank IRA or other retirement account, the applicable funds must be transferred to a self-directed account maintained by an independent custodian or trustee, such as a brokerage firm, and the purchase must be made through that account. If you do not have such an account, you will need to establish one before placing your stock order. An annual administrative fee may be payable to the independent custodian or trustee. Because individual circumstances differ and the processing of retirement fund orders takes additional time, we recommend that you contact our Stock Information Center promptly, preferably at least two weeks before the November 14, 2023 offering deadline, for assistance with purchases using funds in your IRA or other retirement account you may have at Needham Bank or elsewhere. Whether you may use such funds to purchase shares in the offering may depend on timing constraints and, possibly, limitations imposed by the institution where the funds are held.

See “The Conversion and Plan of Distribution – Procedure for Purchasing Shares in the Subscription and Community Offerings – Payment for Shares” and “ – Using Retirement Account Funds” for a complete description of how to use IRA funds to purchase shares of common stock in the offering.

Purchases by Executive Officers and Directors and Ownership by Benefit Plans

We expect our directors and executive officers, together with their associates, to subscribe for 762,500 shares ($7,625,000) of common stock in the offering, or 3.0% of the shares to be sold at the minimum of the offering range (excluding shares issued to our charitable foundation). Our directors and executive officers will pay the same $10.00 per share price for the common stock as all other subscribers in the offering. Purchases of the common stock by our directors and executive officers are for investment purposes for these individuals and not with a view towards resale, and pursuant to applicable conversion regulations, our directors and executive officers generally will not be permitted to sell any shares of the common stock that they purchase in the offering for a period of at least one year from the closing of the conversion and offering. See “Subscriptions by Directors and Executive Officers.”

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Additionally, we expect our ESOP to purchase 8% of the total number of shares of common stock that we issue in the offering (including shares contributed to our charitable foundation), and also expect, following completion of the conversion, and subject to stockholder approval, to adopt and implement one or more stock-based benefit plans. The shares owned by these plans will increase the ownership of our officers and directors. See “ – Benefits to Management and Potential Dilution to Stockholders Following the Conversion.”

How We Intend to Use the Proceeds From the Offering

Assuming we sell 31,000,000 shares of common stock in the offering, the midpoint of the offering range, and we have net proceeds of $303.2 million, we intend to distribute the net proceeds as follows:

· $151.6 million (50.0% of the net proceeds) will be invested in Needham Bank;

· $25.8 million (8.5% of the net proceeds) will be loaned to our ESOP to fund its purchase of our shares of common stock;

· $2.0 million (0.8% of the net proceeds) will be contributed to our charitable foundation; and

· $123.8 million (40.7% of the net proceeds) will be retained by NB Bancorp. We may use the funds we receive for investments, to pay cash dividends, to repurchase shares of common stock and for other general corporate purposes, subject to regulatory approval as applicable. Needham Bank may use the proceeds from the offering it receives from NB Bancorp to support increased lending and to increase its capital position. The net proceeds retained by NB Bancorp and Needham Bank also may be used for future business expansion through de novo branching and/or branch acquisitions. We have no current arrangements or agreements with respect to any such branching. Initially, a substantial portion of the net proceeds will be invested in short-term investments consistent with our investment policy.

We do not anticipate the number of shares we sell in the offering will result in significant changes in the respective uses of proceeds by Needham Bank and NB Bancorp. Please see the section of this prospectus entitled “How We Intend to Use the Proceeds From the Offering” for more information on the proposed use of the proceeds from the offering, including a table showing the distribution of net proceeds at different points in the offering range.

Our Contribution of Cash and Shares of Our Common Stock to Needham Bank Charitable Foundation

To further our commitment to our local community, we have established a charitable foundation as part of the conversion and offering and have received approval from our depositors to fund the charitable foundation with shares of our common stock and cash. Such contribution will consist of $2.0 million in cash and a number of shares of our common stock equal to 4% of the shares that will be outstanding immediately after this contribution. As a result of the issuance of shares of common stock and the contribution of cash to the charitable foundation, at the maximum of the offering range, we will record an after-tax expense of approximately $12.3 million during the quarter in which the offering is completed.

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The charitable foundation will be dedicated exclusively to supporting charitable causes and community development activities in the communities in which we operate now and in the future. The charitable foundation will be required to distribute annually in grants or donations a minimum of 5% of the average fair market value of its net investment assets. Assuming we close the stock offering at the maximum of the offering range, the charitable foundation is expected to make contributions totaling approximately $819,000 in its first year of operation.

Issuing shares of common stock and contributing cash to the charitable foundation will:

· dilute the voting interests of purchasers of shares of our common stock in the offering; and

· result in an expense, and a reduction in earnings, during the quarter in which the contribution is made, equal to the full amount of the contribution to the charitable foundation, offset in part by a corresponding tax benefit.

The amount of common stock that we would offer for sale would be greater if the offering were to be completed without the formation and funding of Needham Bank Charitable Foundation. For a further discussion of the financial impact of the charitable foundation, including its effect on those who purchase shares in the offering, see “Risk Factors – Risks Related to the Charitable Foundation – The contribution to the charitable foundation will dilute your ownership interest and adversely affect net income in the year in which we consummate the Conversion” and “Needham Bank Charitable Foundation.”

You May Not Sell or Transfer Your Subscription Rights

Applicable regulations prohibit you from transferring your subscription rights. If you order shares of common stock in the subscription offering, you will be required to state that you are purchasing the shares of common stock for yourself and that you have no agreement or understanding to sell or transfer your subscription rights. We intend to take legal action, including reporting persons to federal or state regulatory agencies, against anyone who we believe has sold or given away his or her subscription rights. We will not accept your order if we have reason to believe that you have sold or transferred your subscription rights.

When registering your stock purchase on the stock order form, you cannot add the name(s) of others for joint stock registration unless they are also named on the qualifying deposit account, and you cannot delete names of others except in the case of certain orders placed through an IRA, 401(k) or similar plan, and except in the event of death of a named eligible depositor. In addition, the stock order form requires that you list all qualifying accounts, giving all names on each account and the account number at the applicable eligibility date. Failure to provide this information, or providing incomplete or incorrect information, may result in a loss of part or all of your share allocation if there is an oversubscription.

Deadline for Orders of Shares of Common Stock in the Subscription and Community Offerings

If you wish to purchase shares of common stock in the offering, we must receive a properly signed and completed original stock order form, together with full payment for the shares of common stock, no later than 4:00 p.m., Eastern Time, on November 14, 2023, unless we extend the subscription offering and/or the community offering. Orders received after 4:00 p.m., Eastern Time, on November 14, 2023 will be rejected unless we extend the offering. If you wish to purchase shares of common stock, a properly completed and signed original stock order form, together with full payment, must be received (not postmarked) by this time.

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Although we will make reasonable attempts to provide this prospectus and offering materials to holders of subscription rights, the subscription offering and all subscription rights will expire at 4:00 p.m., Eastern Time, on November 14, 2023, whether or not we have been able to locate each person entitled to subscription rights.

For a complete description of the deadline for purchasing shares in the offering, see “The Conversion and Plan of Distribution – Procedure for Purchasing Shares – Expiration Date.”

Steps We May Take If We Do Not Receive Orders for the Minimum Number of Shares

If we do not receive orders for at least 26,350,000 shares of common stock (not counting shares to be contributed to our charitable foundation), we may take additional steps to complete the offering. Specifically, we may:

· increase the purchase limitations; and/or

· seek regulatory approval, to the extent required, to extend the offering beyond December 29, 2023, so long as we resolicit persons that have previously subscribed in the offering.

If we extend the offering past December 29, 2023, we will resolicit subscribers. You will have the opportunity to confirm, change or cancel your order within a specified period of time. If you do not respond during that period of time, your stock order will be cancelled and your deposit account withdrawal authorizations will be cancelled or your funds submitted will be returned promptly with interest at 0.05% from the date the stock order was processed. If one or more purchase limitations are increased, subscribers in the subscription offering who ordered the maximum amount will be given the opportunity to increase their subscriptions up to the newly applicable limit.

Possible Change in the Offering Range

RP Financial, LC. will update its appraisal before we complete the offering. If, as a result of demand for the shares, changes in market conditions or changes to our financial condition, operating results or other aspects of our business, RP Financial, LC. determines that our pro forma market value has increased, we may sell up to 40,997,500 shares in the offering without further notice to you. If our pro forma market value at that time is either below $263.5 million or above $410.0 million, then, after consulting with the Federal Reserve Board and the Commissioner, we may:

· terminate the offering, cancel deposit account withdrawal authorizations and promptly return all funds received in the offering with interest at 0.05%;

· set a new offering range; or

· take such other actions as may be permitted, to the extent such permission is required, by the Commissioner, the Federal Reserve Board, the SEC and the Financial Industry Regulatory Authority, or “FINRA”.

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If we set a new offering range, we will promptly return funds, with interest at 0.05% for funds received in the offering, cancel deposit account withdrawal authorizations and commence a resolicitation. In connection with the resolicitation, we will notify subscribers of their right to place a new stock order for a specified period of time.

Possible Termination of the Offering

We may terminate the offering at any time with the approval, to the extent such approval is required, of the Commissioner and the Federal Reserve Board.

We must sell a minimum of 26,350,000 shares to complete the offering (not including the shares that we will contribute to the charitable foundation). If we terminate the offering because we fail to sell the minimum number of shares or for any other reason, we will promptly return your funds with interest at 0.05%, and we will cancel deposit account withdrawal authorizations.

Conditions to Completion of the Conversion and the Offering

We cannot complete the conversion and the offering unless:

· the plan of conversion is approved by a majority of the votes cast by members of NB Financial, MHC, who are the depositors of Needham Bank, at a special meeting of members of NB Financial, MHC. A special meeting of the members of NB Financial, MHC was held on July 26, 2023 at which meeting the members approved the plan of conversion and the establishment and funding of the charitable foundation by the required votes;

· we have received and accepted orders to purchase at least the minimum number of shares of common stock offered; and

· we receive all required final approvals of the Commissioner and the Federal Reserve Board to complete the conversion and the offering.

In addition, the merger of NB Financial, MHC with NB Financial, Inc. was approved by a majority of the corporators of NB Financial, MHC in office and entitled to vote.  The merger was approved at a special meeting of corporators held on July 26, 2023.

Benefits to Management and Potential Dilution to Stockholders Following the Conversion

We expect our ESOP to purchase 8% of the total number of shares of common stock that we issue in the offering (including shares contributed to our charitable foundation), or 2,875,000 shares of common stock, assuming we sell the maximum of the shares proposed to be sold.

We also intend to implement one or more stock-based benefit plans after completion of the conversion and offering. Stockholder approval of these plans will be required, and the stock-based benefit plans cannot be implemented until at least six months after the completion of the conversion pursuant to applicable regulations. We have not yet determined whether we will present these plans for stockholder approval within 12 months following the completion of the conversion or more than 12 months after the completion of the conversion. If presented more than 12 months after the completion of the conversion, these plans would require the approval of our stockholders by a majority of votes cast; otherwise, they would require the approval of our stockholders by a majority of votes eligible to be cast. Further, there are a number of restrictions that would apply to these plans if adopted within one year of the conversion (and with regard to vesting, within three years), including limits on awards to non-employee directors and officers and vesting. See “Management of NB Bancorp – Benefits to be Considered Following Completion of the Offering.” For example, if adopted within 12 months following the completion of the conversion, the stock-based benefit plans will reserve a number of shares of common stock equal to not more than 4% of the shares issued in the conversion (including shares contributed to our charitable foundation) for restricted stock awards to key employees and directors, at no cost to the recipients, and will also reserve a number of stock options equal to not more than 10% of the shares of common stock issued in the conversion (including shares contributed to our charitable foundation) for key employees and directors.

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If 4% of the shares of common stock issued in the conversion (including shares contributed to our charitable foundation) are awarded under a stock-based benefit plan and come from authorized but unissued shares of common stock, stockholders would experience dilution of up to 3.85% in their ownership interest in NB Bancorp. If 10% of the shares of common stock issued in the conversion (including shares contributed to our charitable foundation) are issued upon the exercise of options granted under a stock-based benefit plan and come from authorized but unissued shares of common stock, stockholders would experience dilution of 9.09% in their ownership interest in NB Bancorp.

In connection with the conversion, we expect to establish change in control agreements with certain of our other executive officers. See “Management of NB Bancorp – Executive Compensation” for a further discussion of these agreements, including their terms and potential costs, as well as a description of other benefits arrangements.

The following table summarizes the number of shares of common stock and aggregate dollar value of grants (valuing each share granted at the offering price of $10.00) that will be available under our ESOP and one or more stock-based benefit plans if such plans are adopted within one year following the completion of the conversion and the offering. The table shows the dilution to stockholders if all these shares are issued from authorized but unissued shares, instead of shares purchased in the open market. The table also sets forth the number of shares of common stock to be acquired by the ESOP for allocation to all employees. A portion of the stock awards and stock option grants shown in the table below may be made to non-management employees.

	Number of Shares to be Granted or Purchased (1)							Dilution Resulting			Value of Grants (3)
	At Minimum of Offering Range		At Adjusted Maximum of Offering Range		As a Percentage of Common Stock to be Issued (2)			From Issuance of Shares for Stock Benefit Plans			At Minimum Offering Range		At Adjusted Maximum Offering Range
											(Dollars in thousands)
ESOP		2,195,833		3,416,458		8.00	%		—		$	21,958	$	34,165
Stock awards		1,097,917		1,708,229		4.00			3.85	%		10,979		17,082
Stock options		2,744,792		4,270,573		10.00			9.09	%		13,916		21,652
Total		6,038,542		9,395,260		22.00	%		12.28	%	$	46,853	$	72,899

(1) The stock-based benefit plans may award a greater number of options and shares, respectively, if the plans are adopted more than 12 months after the completion of the conversion.

(2) For plans adopted within 12 months of the completion of the conversion, applicable regulations permit stock awards to encompass up to 4.0% and the ESOP and stock awards to encompass in the aggregate up to 12.0% of the shares issued, provided Needham Bank has tangible capital of 10.0% or more following the conversion.

(3) The actual value of restricted stock awards will be determined based on their fair value as of the date grants are made. For purposes of this table, fair value is assumed to be the same as the offering price of $10.00 per share. The fair value of stock options has been estimated at $5.07 per option using the Black-Scholes option pricing model with the following assumptions: a grant-date share price and option exercise price of $10.00; dividend yield of 0%; an expected option life of 10 years; a risk-free interest rate of 3.81%; and a volatility rate of 32.30% based on an index of publicly traded thrift institutions. The actual expense of stock options granted under a stock-based benefit plan will be determined by the grant-date fair value of the options, which will depend on a number of factors, including the valuation assumptions used in the option pricing model ultimately adopted, which may or may not be the Black-Scholes model.

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Market for Common Stock

We anticipate that the common stock sold in the offering will be listed on the Nasdaq Capital Market under the symbol “NBBK” following the completion of the offering. Piper Sandler & Co. has advised us that it intends to make a market in our common stock following the conversion and offering, but it is under no obligation to do so. See “Market for the Common Stock.”

Our Policy Regarding Dividends

Following completion of the offering, our board of directors will have the authority to declare dividends on our shares of common stock. The board’s determination of whether to declare a dividend and the amount of any such dividend is subject to our capital requirements, our financial condition and results of operations, tax considerations, statutory and regulatory limitations, and general economic conditions. No decision has been made with respect to the amount, if any, and timing of any dividend payments. We cannot assure you that we will pay dividends in the future, or that any such dividends will not be reduced or eliminated in the future. For information regarding our proposed dividend policy, see “Our Policy regarding Dividends.”

Material Income Tax Consequences

The conversion qualifies as a tax-free reorganization. None of NB Financial, MHC, NB Financial, Inc., NB Bancorp, Needham Bank, nor persons eligible to subscribe in the subscription offering will recognize any gain or loss as a result of the conversion. See “The Conversion and Plan of Distribution – Material Income Tax Consequences” for a complete discussion of the income tax consequences of the transaction.

Delivery of Shares of Common Stock

All shares of common stock of NB Bancorp sold in the subscription offering and community offering will be issued in book entry form and held electronically on the books of our transfer agent. Stock certificates will not be issued. A statement reflecting ownership of shares of common stock sold in the offering will be mailed by our transfer agent to the persons entitled thereto at the address noted by them on their stock order form as soon as practicable following consummation of the conversion. Shares of common stock sold in the syndicated community offering may be delivered electronically through the services of The Depository Trust Company. We expect trading in the stock to begin on the business day of or on the business day immediately following the completion of the conversion and offering. It is possible that until a statement reflecting ownership of shares of common stock is available and delivered to purchasers, purchasers might not be able to sell the shares of common stock that they ordered, even though the common stock will have begun trading. Your ability to sell the shares of common stock before receiving your statement will depend on arrangements you may make with a brokerage firm.

Emerging Growth Company Status

We qualify as an “emerging growth company” under the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”). For as long as we are an emerging growth company, we may choose to take advantage of exemptions from various reporting requirements applicable to other public companies but not to emerging growth companies. See “Risk Factors – Risks Related to the Offering – We are an emerging growth company, and any decision on our part to comply only with certain reduced reporting and disclosure requirements applicable to emerging growth companies could make our common stock less attractive to investors” and “Regulation and Supervision – Emerging Growth Company Status.”

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We may remain an emerging growth company for up to five years from the closing of the offering, or until the earliest of (i) the last day of the first fiscal year in which our annual gross revenues exceed $1.24 billion, (ii) the date that we become a “large accelerated filer” as defined in Rule 12b-2 under the Securities Exchange Act of 1934, as amended, or the “Exchange Act,” which would occur if the market value of our common stock that is held by non-affiliates exceeds $700 million as of the last business day of our most recently completed second fiscal quarter, or (iii) the date on which we have issued more than $1 billion in non-convertible debt during the preceding three-year period.

An emerging growth company may elect to use the extended transition period to delay adoption of new or revised accounting pronouncements applicable to public companies until such pronouncements are made applicable to private companies, but must make such election when the company is first required to file a registration statement. Such an election is irrevocable during the period a company is an emerging growth company. We have elected to use the extended transition period to delay adoption of new or revised accounting pronouncements applicable to public companies until such pronouncements are made applicable to private companies. Accordingly, our financial statements may not be comparable to the financial statements of public companies that comply with such new or revised accounting standards.

Important Risks in Owning NB Bancorp’s Common Stock

An investment in our common stock involves substantial risks and uncertainties. Investors should carefully consider all of the information in this prospectus, including the detailed discussion of these and other risks under “Risk Factors” beginning on page 18, before investing in our common stock.

Specific areas of risk related to our business include those related to: our lending activities; market interest rates; economic conditions; our funding and liquidity; laws and regulations; our business strategy; competitive matters; operational matters; accounting matters; our reputation and business.

Specific risks related to this offering include those related to the future trading price of our common stock; the use of the net offering proceeds; the trading market for our common stock; our return on equity after the completion of the offering; intended new stock-based benefit plans; anti-takeover factors; a forum selection provision for certain litigation; the irrevocability of your investment decision; potential adverse tax consequences related to subscription rights; and our contribution to our charitable foundation.

Before making an investment decision, you should read this entire document carefully, including the section entitled “Risk Factors” that immediately follows and that discusses the above risks in further detail.

How You Can Obtain Additional Information – Stock Information Center

Our banking personnel may not, by law, assist with investment-related questions about the offering. If you have questions regarding the conversion or offering, please call our Stock Information Center. The toll-free telephone number is (844) 305-2265. The Stock Information Center is open Monday through Friday, between 10:00 a.m. and 4:00 p.m., Eastern Time. The Stock Information Center will be closed on bank holidays.

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TO ENSURE THAT EACH PERSON IN THE OFFERING RECEIVES A PROSPECTUS AT LEAST 48 HOURS PRIOR TO THE EXPIRATION DATE OF NOVEMBER 14, 2023 AND IN ACCORDANCE WITH FEDERAL LAW, NO PROSPECTUS WILL BE MAILED OR HAND-DELIVERED ANY LATER THAN FIVE DAYS OR TWO DAYS, RESPECTIVELY, PRIOR TO NOVEMBER 14, 2023.

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RISK FACTORS

You should carefully consider the following risk factors that may affect our business, future operating results and financial condition, as well as the other information set forth in this prospectus, before making a decision to invest in our common stock. If any of the following risks actually occur, our business, financial condition or results of operations would likely be materially adversely affected. In such case, the trading price of our common stock would likely decline due to any of these risks, and you may lose all or part of your investment. The following risks are not the only risks we face. Additional risks that are not presently known or that we presently deem to be immaterial also could have a material adverse effect on our financial condition, results of operations and business.

Risks Related to our Lending Activities

Our portfolios of commercial real estate loans and commercial and industrial loans have increased in recent periods, and we intend to continue originating these types of loans. These loans involve credit risks that could adversely affect our financial condition and results of operations.

At June 30, 2023, commercial real estate and multifamily loans and construction and land development loans, totaled $1.80 billion, or 51.0% of our loan portfolio, and commercial and industrial loans totaled $431.3 million, or 12.2% of our loan portfolio. These loans generally have more risk than the one-to four-family residential real estate loans we originate. Such loans typically involve larger loan balances to single borrowers or groups of related borrowers compared to one- to four-family residential mortgage loans. In addition, the repayment of these types of loans depends on the successful management and operation of the borrower’s businesses or properties. The repayment of such loans can be affected by adverse conditions in the local real estate market or economy. Also, many of our commercial borrowers have more than one loan outstanding with us. At June 30, 2023, our loans-to-one borrower limit was $80.7 million and our four largest borrower relationships, including available lines of credit, were $71.7 million, $70.0 million, $68.5 million and $67.6 million, respectively. Further, the offering will allow us to increase our loans-to-one borrower limit, which may result in larger loan balances. Consequently, an adverse development with respect to one loan or one credit relationship can expose us to a significantly greater risk of loss compared to an adverse development with respect to a one- to four-family residential real estate loan. Commercial and industrial loans expose us to additional risk since they typically are dependent on the borrower’s ability to make repayments from the cash flows of the business and are secured by non-real estate collateral that may depreciate over time. Further, our commercial and industrial loans may be secured by collateral other than real estate, such as inventory and accounts receivable, the value of which may be more difficult to appraise, control or collect and may be more susceptible to fluctuation in value at the time of default. In addition, if we foreclose on commercial real estate loans, our holding period for the collateral may be longer than for a single-family residential property if there are fewer potential purchasers of the collateral. Furthermore, if loans that are collateralized by commercial real estate become troubled and the value of the real estate has been significantly impaired, then we may not be able to recover the full contractual amount of principal and interest that we anticipated at the time we originated the loan. Any of these risks could cause us to increase our provision for credit losses and adversely affect our operating results and financial condition.

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The level of our commercial real estate loan portfolio subjects us to additional regulatory scrutiny.

The Federal Reserve Board and the other federal bank regulatory agencies have promulgated joint guidance on sound risk management practices for financial institutions with concentrations in commercial real estate lending. Under the guidance, a financial institution that is actively involved in commercial real estate lending should perform a risk assessment to identify concentrations. A financial institution may have a concentration in commercial real estate lending if, among other factors, (i) total reported loans for construction, land acquisition and development, and other land represent 100% or more of total capital, or (ii) total reported loans secured by multifamily and non-farm residential properties, loans for construction, land acquisition and development and other land, and loans otherwise sensitive to the general commercial real estate market, including loans to non-owner occupied commercial real estate related entities, represent 300% or more of total capital.

Based on these factors we have a concentration in commercial real estate lending, as such loans represent approximately 344.1% of our total capital as of June 30, 2023. The guidance focuses on exposure to commercial real estate loans that is dependent on the cash flow from the real estate held as collateral and that is likely to be at greater risk to conditions in the commercial real estate market (as opposed to real estate collateral held as a secondary source of repayment or as an abundance of caution). The guidance assists banks in developing risk management practices and capital levels commensurate with the level and nature of real estate concentrations. The guidance states that management should employ heightened risk management practices including board and management oversight and strategic planning, development of underwriting standards, risk assessment and monitoring through market analysis and stress testing. While we believe we have implemented policies and procedures with respect to our commercial real estate loan portfolio consistent with this guidance, bank regulators could require us to implement additional policies and procedures consistent with their interpretation of the guidance that may result in additional costs to us or that may result in a curtailment of our commercial real estate lending, including multifamily and construction and land development lending, and/or the requirement that we maintain higher levels of regulatory capital, either of which would adversely affect our loan originations and profitability.

Our construction and land development loans involve credit risks that could adversely affect our financial condition and results of operations.

At June 30, 2023, construction loans and loans to finance the acquisition of developable land which we refer to as “land development loans” totaled $568.0 million, or 16.1% of our loan portfolio. Construction lending involves additional risks when compared with permanent finance lending because funds are advanced upon the security of the project, which is of uncertain value before its completion. Because of the uncertainties inherent in estimating construction costs, as well as the market value of the completed project and the effects of governmental regulation of real property, it is relatively difficult to accurately evaluate the total funds required to complete a project and the related loan-to-value ratio. In addition, generally during the term of a construction loan, interest may be funded by the borrower or disbursed from an interest reserve set aside from the construction loan budget. These loans often involve the disbursement of substantial funds with repayment substantially dependent on the success of the ultimate project and the ability of the borrower to sell or lease the property or obtain permanent take-out financing, rather than the ability of the borrower or guarantor to repay principal and interest. If the appraised value of a completed project proves to be overstated, we may have inadequate security for the repayment of the loan upon completion of construction of the project and may incur a loss. In addition, speculative construction loans, which are loans made to home builders who, at the time of loan origination, have not yet secured an end buyer for the home under construction, typically carry higher risks than those associated with traditional construction loans. These increased risks arise because of the risk that there will be inadequate demand to ensure the sale of the property within an acceptable time. As a result, in addition to the risks associated with traditional construction loans, speculative construction loans carry the added risk that the builder will have to pay the property taxes and other carrying costs of the property until an end buyer is found. Land loans have substantially similar risks to speculative construction loans. As our construction and land loan portfolio increases, the corresponding risks and potential for losses from these loans may also increase.

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Lack of seasoning of certain portions of our commercial and industrial loan portfolio, especially with respect to cannabis, wind and solar customers, may increase the risk of credit defaults in the future.

We have experienced significant loan growth in recent years in our larger commercial and industrial loans, which we refer to as Structured Finance loans. Most of these loans are to new customers in the cannabis, wind and solar industries. We believe we have grown these loan portfolios consistent with prudent underwriting standards but in general, loans do not begin to show signs of credit deterioration or default until they have been outstanding for some period of time, a process referred to as “seasoning.” As a result, a portfolio of older loans will usually behave more predictably than a newer portfolio. It will take several years to determine our borrowers’ payment histories, with respect to many of these new lending relationships and, as a result, we may not be able to reliably evaluate the quality of the loan portfolio until that time.

Our historical emphasis on residential mortgage loans exposes us to lending risks.

At June 30, 2023, $1.01 billion, or 28.7% of our loan portfolio, was secured by one- to four-family residential real estate and we intend to continue to emphasize this type of lending after the offering. One- to four-family residential mortgage lending is generally sensitive to regional and local economic conditions that significantly impact the ability of borrowers to meet their loan payment obligations, making loss levels difficult to predict. Declines in real estate values could cause some of our residential mortgages to be inadequately collateralized, which would expose us to a greater risk of loss if we seek to recover on defaulted loans by selling the real estate collateral.

The geographic concentration of our loan portfolio and lending activities makes us vulnerable to a downturn in the local economy.

We primarily serve individuals and businesses located in the Greater Boston metropolitan area and surrounding communities, including eastern Connecticut, southern New Hampshire and Rhode Island. At June 30, 2023, approximately $2.8 billion, or 79.0% of our total loans, was primarily secured by real estate in this market area. Therefore, our success is largely dependent on the economic conditions, including employment levels, population growth, income levels, savings trends and government policies, in this market area. Although our loan portfolio has very limited exposure to commercial office space in downtown Boston, increased vacancies in this market resulting in depressed prices could have a ripple effect on the Greater Boston Metropolitan area. Moreover, the continued trend of hybrid and remote work would likely result in increased vacancy rates in commercial office space throughout the Greater Boston metropolitan area which could also negatively affect the demand for retail occupancy and sales in surrounding areas, any of which could adversely affect the value of the properties used as collateral for such loans. Similarly, weaker economic conditions caused by recessions, unemployment, inflation, a decline in real estate values or other factors beyond our control may adversely affect the ability of our borrowers to service their debt obligations and could result in higher loan and lease losses and lower net income for us.

Although there is not a single employer or industry in our market area on which a significant number of our customers are dependent, a substantial portion of our loan portfolio is composed of loans secured by property located in the Greater Boston metropolitan area. This makes us vulnerable to a downturn in the local economy and real estate markets. Decreases in local real estate values caused by economic conditions or other events could adversely affect the value of the property used as collateral for our loans, which could cause us to realize a loss in the event of a foreclosure.

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A worsening of business and economic conditions generally or specifically in the principal markets in which we conduct business could have adverse effects on our business, including the following:

· a decrease in the demand for, or the availability of, loans and other products and services offered by us;

· a decrease in the value of our loans or other assets secured by residential or commercial real estate;

· a decrease in interest income from variable rate loans due to declines in interest rates; and

· an increase in the number of customers and counterparties who become delinquent, file for protection under bankruptcy laws or default on their loans or other obligations to us, which could result in a higher level of nonperforming assets, net charge-offs, provisions for credit losses, and valuation adjustments on loans held for sale.

Moreover, a significant decline in general economic conditions, caused by inflation, recession, acts of terrorism, an outbreak of hostilities or other international or domestic calamities, unemployment, public health crises or other factors beyond our control could further impact these local economic conditions and could further negatively affect the financial results of our banking operations. In addition, deflationary pressures, while possibly lowering our operating costs, could have a significant negative effect on our borrowers, especially our business borrowers, and the values of underlying collateral securing loans, which could negatively affect our financial performance. In the event of severely adverse business and economic conditions generally or specifically in the principal markets in which we conduct business, there can be no assurance that the federal government and the Federal Reserve Board would intervene. If economic conditions worsen or volatility increases, our business, financial condition and results of operations could be materially adversely affected. For more information about our market area, please see the section of this prospectus titled “Business of Needham Bank – Market Area.”

If our allowance for credit losses is not sufficient to cover actual credit losses, our earnings could decrease.

We maintain an allowance for credit losses, which is established through a provision for credit losses that represents management’s best estimate of the current expected losses within the loan portfolio. We make various assumptions and judgments about the collectability of our loan portfolio, including the creditworthiness of our borrowers and the value of the real estate and other assets serving as collateral for the repayment of many of our loans. In determining the amount of the allowance for credit losses, we review our loans and our loss and delinquency experience, and we evaluate economic conditions. If our assumptions or the results of our analyses are incorrect, our allowance for credit losses may not be sufficient to cover losses inherent in our loan portfolio, resulting in additions to our allowance. In addition, our emphasis on loan growth and on increasing our portfolios of commercial real estate loans, as well as any future credit deterioration or changes in economic conditions could require us to increase our allowance for credit losses in the future. At June 30, 2023, our allowance for credit losses was 0.89% of total loans and 235% of non-performing loans. Material additions to our allowance would materially decrease our net income.

We adopted the Current Expected Credit Loss, or “CECL,” standard on January 1, 2023. CECL requires financial institutions to determine periodic estimates of lifetime expected credit losses on loans, and recognize the expected credit losses as allowances for credit losses. This has changed the current method of providing allowances for credit losses that are incurred or probable, which has required us to increase our allowance for credit losses, and to greatly increase the types of data we need to collect and review to determine the appropriate level of the allowance for credit losses. Our day one CECL adjustment on January 1, 2023, was $2.1 million, net of tax, and is reflected in our financial statements at and for the three months ended March 31, 2023.

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In addition, bank regulators periodically review our allowance for credit losses and, as a result of such reviews, we may be required to increase our provision for credit losses or recognize further loan charge-offs. However, regulatory agencies are not directly involved in the process of establishing the allowance for credit losses, as the process is our responsibility and any adjustment of the allowance is the responsibility of our management. Any increase in our allowance for credit losses or loan charge-offs as a result of such review or otherwise may have a material adverse effect on our financial condition and results of operations.

We provide banking services to customers who do business in the cannabis industry and the strict enforcement of federal laws regarding cannabis would likely result in our inability to continue to provide banking services to these customers and we could have legal action taken against us by the federal government.

We have deposit and loan customers that are licensed in various States to do business in the cannabis industry as growers, processors, and dispensaries. While cannabis is legal in each of these States, it remains classified as a Schedule I controlled substance under the Federal Controlled Substances Act, or CSA. As such, the cultivation, use, distribution, and possession of cannabis is a violation of federal law that is punishable by imprisonment and fines. Moreover, the U.S. Supreme Court ruled in USA v. Oakland Cannabis Buyers’ Coop. that the federal government has the authority to regulate and criminalize cannabis, including medical marijuana.

In January 2018, the U.S. Department of Justice, or DOJ, rescinded the “Cole Memo” and related memoranda which characterized the enforcement of the CSA against persons and entities complying with state regulatory systems permitting the use, manufacture and sale of medical marijuana as an inefficient use of their prosecutorial resources and discretion. The impact of the DOJ’s rescission of the Cole Memo and related memoranda is unclear, but may result in the DOJ increasing its enforcement actions against the regulated cannabis industry generally.

As in past years, the U.S. Congress has enacted an omnibus spending bill that includes a provision prohibiting the DOJ and the U.S. Drug Enforcement Administration from using funds appropriated by that bill to prevent states from implementing their medical-use cannabis laws. This provision was recently renewed as part of the Consolidated Appropriations Act of 2022. While this provision has been re-enacted every year since 2014, and is expected to continue to be re-enacted in future federal spending bills, if Congress and the President fail to further renew the provision, then the ability of medical cannabis businesses to act in this area, and our ability to provide banking products and services to such businesses, may be impeded. Further, the U.S. Court of Appeals for the Ninth Circuit held in USA v. McIntosh that this provision prohibits the DOJ from spending funds from relevant appropriations acts to prosecute individuals who engage in conduct permitted by state medical-use cannabis laws and who strictly comply with such laws. There is no guarantee that the U.S. Congress will extend this provision or that U.S. Federal courts located outside the Ninth Circuit will follow the ruling in USA v. McIntosh. As of the date of filing this prospectus, we are aware of no federal or state court in or for Massachusetts that has addressed the merits of the McIntosh ruling.

Federal prosecutors have significant discretion and there can be no assurance that a federal prosecutor in any of the federal districts in which we operate will not choose to strictly enforce the federal laws governing cannabis, including medical-use cannabis, or that any of these federal courts will follow the Ninth Circuit’s ruling in USA v. McIntosh. Any change in the federal government’s enforcement position, could cause us to immediately cease providing banking services to the medical-use cannabis industry in the States where we operate.

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Additionally, as the possession and use of cannabis remains illegal under the CSA, we may be deemed to be aiding and abetting illegal activities through the services that we provide to these customers and could have legal action taken against us by the Federal government, including imprisonment and fines. Any change in position or potential action taken against us could result in significant financial damage to us and our stockholders.

The Financial Crimes Enforcement Network, or “FinCEN,” published guidelines in 2014 for financial institutions servicing state legal cannabis business. These guidelines were issued for the explicit purpose so “that financial institutions can provide services to marijuana-related businesses in a manner consistent with their obligations to know their customers and to report possible criminal activity.” Needham Bank has and will continue to follow this and other FinCEN guidance in the areas of cannabis banking. Any adverse change in this FinCEN guidance, any new regulations or legislation, any change in existing regulations or oversight, whether a change in regulatory policy or a change in a regulator’s interpretation of a law or regulation, could have a negative impact on our interest income and noninterest income, as well as the cost of our operations, increasing our cost of regulatory compliance and of doing business, and/or otherwise affect us, which may materially affect our profitability.

Environmental liability associated with our lending activities could result in losses.

In the course of business, we may acquire, through foreclosure, properties securing loans originated or purchased that are in default. Particularly in commercial real estate lending, there is a risk that material environmental violations could be discovered on these properties. In this event, we might be required to remedy these violations at the affected properties at our sole cost and expense. The cost of remedial action could substantially exceed the value of affected properties. We may not have adequate remedies against the prior owner or other responsible parties and could find it difficult or impossible to sell the affected properties. These events could have an adverse effect on our financial condition and results of operations.

Uncertainty about the future of interest rate benchmarks which replace the London Interbank Offered Rate, or “LIBOR,” may adversely affect our business.

LIBOR has been used extensively in the United States as a benchmark for various commercial and financial contracts, including funding sources, adjustable rate mortgages, corporate debt, interest rate swaps and other derivatives. LIBOR is set based on interest rate information reported by certain banks, which stopped reporting such information after June 30, 2023. Other benchmarks may perform differently than LIBOR or may have other consequences that cannot currently be anticipated. It is also uncertain what will happen with instruments that relied on LIBOR for future interest rate adjustments and which of those instruments may remain outstanding or be renegotiated once LIBOR ceases to exist. All of our financial instruments which were set by reference to LIBOR as a benchmark have been converted to a Secured Overnight Financing Rate, or SOFR. The transition from LIBOR to SOFR could have adverse impacts on our funding costs or net interest margins, as well as any floating-rate obligations, loans, deposits, derivatives, and other financial instruments that previously used LIBOR as a benchmark rate and, ultimately, adversely affect our financial condition and results of operations.

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The foreclosure process may adversely impact our recoveries on non-performing loans.

The judicial foreclosure process is protracted, which delays our ability to resolve non-performing loans through the sale of the underlying collateral. The longer timelines have been the result of the economic turmoil largely related shutdowns resulting from the COVID-19 pandemic, additional consumer protection initiatives related to the foreclosure process, increased documentary requirements and judicial scrutiny, and, both voluntary and mandatory programs under which lenders may consider loan modifications or other alternatives to foreclosure. These reasons and the legal and regulatory responses have impacted the foreclosure process and completion time of foreclosures for residential mortgage lenders. This may result in a material adverse effect on collateral values and our ability to minimize its losses.

Risks Related to Market Interest Rates

The reversal of the historically low interest rate environment may adversely affect our net interest income and profitability.

The Federal Reserve Board decreased benchmark interest rates significantly, to near zero, in response to the COVID-19 pandemic. The Federal Reserve Board has reversed its policy of near zero interest rates given its concerns over inflation. Market interest rates have risen significantly in response to the Federal Reserve Board’s recent rate increases. The increase in market interest rates could have an adverse effect on our net interest income and profitability, and we expect that it will have an adverse effect on the present net value of our assets and liabilities and the corresponding value of our equity.

Changes in interest rates could reduce our profits and asset values.

We derive our income mainly from the difference or “spread” between the interest earned on loans, securities and other interest-earning assets and interest paid on deposits, borrowings and other interest-bearing liabilities. In general, the larger the spread, the more we earn. When market rates of interest change, the interest we receive on our assets and the interest we pay on our liabilities will fluctuate. This can cause decreases in our spread and can adversely affect our income. For the past several years, we have been asset sensitive, which indicates that assets generally reprice faster than liabilities. In a rising rate environment, asset sensitivity is preferable as it results in improvement to our net interest margin.

Interest rates also affect how much money we lend. For example, when interest rates rise, the cost of borrowing increases and loan originations tend to decrease. A rising rate environment can also negatively impact us if the higher debt service costs on adjustable-rate loans lead to borrowers’ inability to pay contractual obligations. In addition, changes in interest rates can affect the average life of loans and securities. For example, a reduction in interest rates generally results in increased prepayments of loans and mortgage-backed securities, as borrowers refinance their debt to reduce their borrowing cost. This causes reinvestment risk, because we generally are not able to reinvest prepayments at rates that are comparable to the rates we earned on the prepaid loans or securities in a declining rate environment.

Any substantial, unexpected, prolonged change in market interest rates could have a material adverse effect on our financial condition, liquidity and results of operations. Changes in the level of interest rates also may negatively affect the value of our assets, including the value of our available-for-sale investment securities, which generally decrease when market interest rates rise, and ultimately affect our earnings. During the six months ended June 30, 2023 and the year ended December 31, 2022, we incurred other comprehensive income (losses) of $49,000 and $(12.1) million, respectively, primarily related to net changes in unrealized holding gains (losses) in the available-for-sale investment securities portfolio.

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Changes in the level of interest rates also may negatively affect our ability to originate real estate loans, the value of our assets, and our ability to realize gains from the sale of our assets, all of which ultimately affect our earnings. Also, our interest rate risk modeling techniques and assumptions likely may not fully predict or capture the impact of actual interest rate changes on our balance sheet or projected operating results. See “Management’s Discussion and Analysis of Financial Condition and Results of Operations – Management of Market Risk.”

Hedging against interest rate exposure may adversely affect our earnings.

On occasion we have employed various financial risk methodologies that limit, or “hedge,” the adverse effects of rising or decreasing interest rates on our loan portfolios and short-term liabilities. We also engage in hedging strategies with respect to arrangements where our customers swap floating interest rate obligations for fixed interest rate obligations, or vice versa. Our hedging activity varies based on the level and volatility of interest rates and other changing market conditions. There are no perfect hedging strategies, and interest rate hedging may fail to protect us from loss. Moreover, hedging activities could result in losses if the event against which we hedge does not occur. Additionally, interest rate hedging could fail to protect us or adversely affect us because, among other things:

· available interest rate hedging may not correspond directly with the interest rate risk for which protection is sought;

· the duration of the hedge may not match the duration of the related liability;

· the party owing money in the hedging transaction may default on its obligation to pay;

· the credit quality of the party owing money on the hedge may be downgraded to such an extent that it impairs our ability to sell or assign our side of the hedging transaction;

· the value of derivatives used for hedging may be adjusted from time to time in accordance with accounting rules to reflect changes in fair value; and/or

· downward adjustments, or “mark-to-market” losses, would reduce our stockholders’ equity.

Risks Related to Economic Conditions

Inflation can have an adverse impact on our business and on our customers.

Inflation risk is the risk that the value of assets or income from investments will be worth less in the future as inflation decreases the value of money. Recently, there has been a rise in inflation and the Federal Reserve Board has raised certain benchmark interest rates in an effort to combat inflation. As discussed above under “– Risks Related to Market Interest Rates – Changes in interest rates could reduce our profits and asset values,” as inflation increases and market interest rates rise, the value of our investment securities, particularly those with longer maturities, would decrease, although this effect can be less pronounced for floating rate instruments. In addition, inflation generally increases the cost of goods and services we use in our business operations, such as electricity and other utilities, which increases our noninterest expenses. Furthermore, our customers are also affected by inflation and the rising costs of goods and services used in their households and businesses, which could have a negative impact on their ability to repay their loans with us.

A worsening of economic conditions in our market area could reduce demand for our products and services and/or result in increases in our level of non-performing loans, which could adversely affect our operations, financial condition and earnings.

Local and regional economic conditions have a significant impact on the ability of our borrowers to repay loans and the value of the collateral securing loans. A deterioration in economic conditions, especially local conditions, could have the following consequences, any of which could have a material adverse effect on our business, financial condition, liquidity and results of operations, and could more negatively affect us compared to a financial institution that operates with more geographic diversity:

· demand for our products and services may decline;

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· loan delinquencies, problem assets and foreclosures may increase;

· collateral for loans, especially real estate, may decline in value, thereby reducing customers’ future borrowing power, and reducing the value of assets and collateral associated with existing loans, causing an increase in our allowance for credit losses; and

· the net worth and liquidity of loan guarantors may decline, impairing their ability to honor commitments to us.

Moreover, a significant decline in general economic conditions caused by inflation, recession, acts of terrorism, civil unrest, an outbreak of hostilities or other international or domestic calamities, an epidemic or pandemic, unemployment or other factors beyond our control could further impact these local economic conditions and could further negatively affect the financial results of our banking operations. In addition, deflationary pressures, while possibly lowering our operating costs, could have a significant negative effect on our borrowers, especially our business borrowers, and the values of underlying collateral securing loans, which could negatively affect our financial performance.

Further, a U.S. government debt default would have a material adverse impact on our business and financial performance, including a decrease in the value of U.S. Treasury securities and other government securities held by us, which could negatively impact our capital position and our ability to meet regulatory requirements. Other negative impacts could be volatile capital markets, an adverse impact on the U.S. economy and the U.S. dollar, as well as increased default rates among borrowers in light of increased economic uncertainty. Some of these impacts might occur even in the absence of an actual default but as a consequence of extended political negotiations around the threat of such a default and a government shutdown.

We have a high concentration of loans secured by real estate in our market area. Adverse economic conditions, both generally and in our market area, could adversely affect our financial condition and results of operations.

Most of our loans are inside of our market area and, as a result, we have a greater risk of loan defaults and losses in the event of a further economic downturn in our market area, as adverse economic conditions may have a negative effect on the ability of our borrowers to make timely payments of their loans. A return of recessionary conditions and/or negative developments in the domestic and international credit markets may significantly affect the markets in which we do business, the value of our loans, investments, and collateral securing our loans, and our ongoing operations, costs and profitability. Any of these negative events may result in higher-than-expected loan delinquencies, increase our levels of nonperforming and classified assets, and reduce demand for our products and services, which may cause us to incur losses and may adversely affect our capital, liquidity and financial condition.

Adverse developments affecting the financial services industry, such as actual events or concerns involving liquidity, defaults, or non-performance by financial institutions or transactional counterparties, could adversely affect our financial condition and results of operations.

Actual events involving limited liquidity, defaults, non-performance or other adverse developments that affect financial institutions, transactional counterparties or other companies in the financial services industry or the financial services industry generally, or concerns or rumors about any events of these kinds or other similar risks, have in the past and may in the future lead to market-wide liquidity problems. For example, on May 1, 2023, First Republic Bank went into receivership and its deposits and substantially all of its assets were acquired by JPMorgan Chase Bank, National Association. Similarly, on March 10, 2023, Silicon Valley Bank went into receivership, and on March 12, Signature Bank went into receivership.

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Inflation and rapid increases in interest rates have led to a decline in the trading value of previously issued government securities with interest rates below current market interest rates. Although the Treasury, FDIC and Federal Reserve Board have announced a program to provide up to $25 billion of loans to financial institutions secured by certain of such government securities held by financial institutions to mitigate the risk of potential losses on the sale of such instruments, widespread demands for customer withdrawals or other liquidity needs of financial institutions for immediately liquidity may exceed the capacity of such program. Additionally, there is no guarantee that the Treasury, FDIC and Federal Reserve Board will provide access to uninsured funds in the future in the event of the closure of other banks or financial institutions, or that they would do so in a timely fashion.

Inflationary pressures and rising prices may affect our results of operations and financial condition.

Inflation rose sharply at the end of 2021 and throughout 2022. Inflationary pressures are currently expected to remain elevated throughout 2023. Small to medium-sized businesses may be impacted more during periods of high inflation as they are not able to leverage economics of scale to mitigate cost pressures compared to larger businesses. Consequently, the ability of our business customers to repay their loans may deteriorate, and in some cases this deterioration may occur quickly, which would adversely impact our results of operations and financial condition. Furthermore, a prolonged period of inflation could cause wages and other costs increase, which could adversely affect our results of operations and financial condition.

Our securities portfolio performance in difficult market conditions could have adverse effects on our results of operations.

Unrealized losses on investment securities result from changes in credit spreads and liquidity issues in the marketplace, along with changes in the credit profile of individual securities issuers. Under GAAP, we are required to review our investment portfolio periodically for the presence of credit losses of our securities, taking into consideration current and future market conditions, the extent and nature of changes in fair value, issuer rating changes and trends, volatility of earnings, current analysts’ evaluations, our ability and intent to hold investments until a recovery of fair value, as well as other factors. Adverse developments with respect to one or more of the foregoing factors may require us to deem particular securities to be impaired, with the credit-related portion of the reduction in the value recognized as a charge to our earnings through an allowance. Subsequent valuations, in light of factors prevailing at that time, may result in significant changes in the values of these securities in future periods. Any of these factors could require us to recognize further impairments in the value of our securities portfolio, which may have an adverse effect on our results of operations in future periods.

The fair value of our investment securities can fluctuate due to factors outside of our control.

Factors beyond our control can significantly influence the fair value of securities in our portfolio and can cause potential adverse changes to the fair value of these securities. These factors include, but are not limited to, rating agency actions with respect to individual securities, defaults by the issuer or with respect to the underlying securities, and changes in market interest rates and continued instability in the capital markets. Any of these factors, among others, could cause credit losses and realized and/or unrealized losses in future periods and declines in other comprehensive income, which could materially and adversely affect our business, results of operations, financial condition and prospects. The process for determining whether impairment of a security is related to credit usually requires complex, subjective judgments about the future financial performance and liquidity of the issuer and any collateral underlying the security in order to assess the probability of receiving all contractual principal and interest payments on the security. Significant negative changes to valuations could result in credit losses on our securities portfolio, which could have an adverse effect on our financial condition or results of operations. As of June 30, 2023, we had approximately $14.4 million of accumulated other comprehensive losses. During the six months ended June 30, 2023, we had $49,000 of after-tax other comprehensive income, which resulted primarily from $350,000 in unrealized valuation gains on available-for-sale investment securities.

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Potential downgrades of U.S. government securities by one or more of the credit ratings agencies could have a material adverse effect on our operations, earnings and financial condition.

A possible future downgrade of the sovereign credit ratings of the U.S. government and a decline in the perceived creditworthiness of U.S. government-related obligations could impact our ability to obtain funding that is collateralized by affected instruments, as well as affect the pricing of that funding when it is available. A downgrade may also adversely affect the market value of such instruments. We cannot predict if, when or how any changes to the credit ratings or perceived creditworthiness of these organizations will affect economic conditions. Such ratings actions could result in a significant adverse impact on us. Among other things, a downgrade in the U.S. government’s credit rating could adversely impact the value of our securities portfolio and may trigger requirements that we post additional collateral for trades relative to these securities. A downgrade of the sovereign credit ratings of the U.S. government or the credit ratings of related institutions, agencies or instruments would significantly exacerbate the other risks to which we are subject and any related adverse effects on the business, financial condition and results of operations.

The soundness of other financial institutions could adversely affect us.

Our ability to engage in routine funding transactions could be adversely affected by the actions and commercial soundness of other financial institutions. Financial services institutions are interrelated as a result of trading, clearing, counterparty and other relationships. We have exposure to many different counterparties, and we routinely execute transactions with counterparties in the financial industry, including brokers and dealers, other commercial banks, investment banks, mutual and hedge funds, and other financial institutions. As a result, defaults by, or even rumors or questions about, one or more financial services institutions, or the financial services industry generally, could lead to market-wide liquidity problems and losses or defaults by us or by other institutions and organizations. Many of these transactions expose us to credit risk in the event of default of our counterparty or client. In addition, our credit risk may be exacerbated when the collateral held by us cannot be liquidated or is liquidated at prices not sufficient to recover the full amount of the financial instrument exposure due to us. There is no assurance that any such losses would not materially and adversely affect our results of operations.

Risks Related to Our Funding

Our inability to generate core deposits may cause us to rely more heavily on wholesale funding strategies for funding and liquidity needs, which could have an adverse effect on our net interest margin and profitability.

We must maintain sufficient funds to respond to the needs of depositors and borrowers. Deposits have traditionally been our primary source of funds for use in lending and investment activities. We also receive funds from loan repayments, investment maturities and income on other interest-earning assets. While we emphasize generating transaction accounts, we cannot guarantee if and when this will occur. Further, the considerable competition for deposits in our market area also has made, and may continue to make, it difficult for us to obtain reasonably priced deposits. Moreover, deposit balances can decrease if customers perceive alternative investments as providing a better risk/return tradeoff. If we are not able to increase our lower-cost transactional deposits at a level necessary to fund our asset growth or deposit outflows, we may be forced seek other sources of funds, including other certificates of deposit, FHLB advances, brokered deposits and lines of credit to meet the borrowing and deposit withdrawal requirements of our customers, which may be more expensive and have an adverse effect on our net interest margin and profitability. In addition, if our capital levels fell such that we were no longer considered “well capitalized,” under federal law we would be subject to restrictions on accepting brokered deposits and on paying above-market rates for deposits. Additionally, if, based on a decrease in our tangible equity, the FHLB were to determine that we have inadequate capital levels, in its discretion, it may limit our ability to utilize FHLB advances.

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Additionally, through our April 2022 purchase of cannabis-related and money service businesses from another financial institution, we acquired approximately $297.7 million of deposits.  At June 30, 2023, this portfolio was approximately $283.9 million. Of this total, approximately $239.9 million are cannabis-related deposits.  Due to the unique industry-specific risks of this business, if we were forced to terminate this business line, we could lose many or most of these deposits, all of which are core deposits.

Our funding sources may prove insufficient to replace deposits at maturity and support our future growth.

We must maintain sufficient funds to respond to the needs of depositors and borrowers. As a part of our liquidity management, we use a number of funding sources in addition to core deposit growth and repayments and maturities of loans and investments. As we continue to grow, we are likely to become more dependent on these sources, which may include FHLB advances, proceeds from the sale of loans, federal funds purchased and brokered certificates of deposit. Adverse operating results or changes in industry conditions could lead to difficulty or an inability to access these additional funding sources. Our financial flexibility will be severely constrained if we are unable to maintain our access to funding or if adequate financing is not available to accommodate future growth at acceptable interest rates. If we are required to rely more heavily on more expensive funding sources to support future growth, our revenues may not increase proportionately to cover our costs. In this case, our operating margins and profitability would be adversely affected.

Risks Related to Laws and Regulations

Changes in laws and regulations and the cost of regulatory compliance with new laws and regulations may adversely affect our operations and/or increase our costs of operations.

Needham Bank is subject to extensive regulation, supervision and examination by the Commissioner and the Federal Reserve Board, and, also by the FDIC as insurer of Needham Bank’s deposit accounts and, upon completion of the conversion and offering, NB Bancorp will be subject to extensive regulation, supervision and examination by the Federal Reserve Board. Such regulation and supervision govern the activities in which an institution and its holding company may engage and are intended primarily for the protection of the federal deposit insurance fund and the depositors of Needham Bank, rather than for our stockholders. Regulatory authorities have extensive discretion in their supervisory and enforcement activities, including the imposition of restrictions on our operations, the classification of our assets and determination of the adequacy of the level of our allowance for credit losses. These regulations, along with existing tax, accounting, securities, insurance and monetary laws, rules, standards, policies, and interpretations, control the methods by which financial institutions conduct business, implement strategic initiatives and tax compliance, and govern financial reporting and disclosures. Any change in such regulation and oversight, whether in the form of regulatory policy, regulations, legislation or supervisory action, may have a material impact on our operations.

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Our cannabis-related business, money service business and ATM business present compliance risks that are different in kind or degree compared to those that we are accustomed to managing and have required us to implement new or enhance existing procedures, systems and controls.

Our April 2022 acquisition resulted in our operation of three different business lines that are new to us and have necessitated robust compliance policies and procedures in order to comply with various laws and regulations. We provide depository services to cannabis businesses, including cannabis retailers and cannabis dispensaries. We also provide loans to various cannabis-related businesses. We also provide depository services to money service businesses and ATM businesses.

These acquired portfolios are mature portfolios which have been previously reviewed and managed by the management team and employees now employed by Needham Bank who were previously employed by the selling institution. However, these business lines are relatively new to us and have required, and we expect will continue to require, proportionately greater compliance and risk management resources than our other business lines in order for us to comply with laws and regulations related to the prevention of financial crimes and combating terrorism, including the U.S. Patriot Act of 2001. These laws and regulations require us to, among other things, implement specific policies and procedures related to those business lines, including enhanced licensing procedures and policies, and anti-money laundering, anti-bribery and corruption, fraud, compliance, suspicious activities, currency transaction reporting, and due diligence on new and existing customers.

With respect to cannabis-related businesses, the Controlled Substances Act makes it illegal under federal law to manufacture, distribute, or dispense cannabis, and therefore federal law, including the money laundering statutes and the Bank Secrecy Act, apply to cannabis-related conduct. Financial transactions involving proceeds generated by cannabis-related conduct can form the basis for prosecution under the money laundering statutes. Financial institutions must report currency transactions and conduct suspicious activity monitoring and reporting in connection with cannabis-related businesses to FinCEN.

Our ability to comply with anti-money laundering laws and our reporting obligations to FinCEN depend on our ability to maintain robust customer due diligence, surveillance, detection, reporting and analytic capabilities. Although we believe that we have policies, systems and procedures designed to comply with these laws and regulations, to the extent our policies or procedures are not fully effective or do not meet heightened regulatory standards or expectations, we may be subject to fines, penalties, restrictions on certain activities including future acquisitions, reputational harm, or other adverse consequences from our federal bank regulators, the Department of Justice or FinCEN.

Non-compliance with the USA PATRIOT Act, Bank Secrecy Act, or other laws and regulations could result in fines or sanctions.

The USA PATRIOT and Bank Secrecy Acts require financial institutions to develop programs to prevent financial institutions from being used for money laundering and terrorist activities. If such activities are suspected, financial institutions are obligated to file suspicious activity reports with FinCEN. These rules require financial institutions to establish procedures for identifying and verifying the identity of customers seeking to open new financial accounts. Failure to comply with these regulations could result in fines or sanctions, including restrictions on pursuing acquisitions or establishing new branches. The policies and procedures we have adopted that are designed to assist in compliance with these laws and regulations may not be effective in preventing violations of these laws and regulations. Furthermore, these rules and regulations continue to evolve and expand.

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Monetary policies and regulations of the Federal Reserve Board could adversely affect our business, financial condition and results of operations.

In addition to being affected by general economic conditions, our earnings and growth are affected by the policies of the Federal Reserve Board. An important function of the Federal Reserve Board is to regulate the money supply and credit conditions. Among the instruments used by the Federal Reserve Board to implement these objectives are open market purchases and sales of U.S. government securities, adjustments of the discount rate and changes in banks’ reserve requirements against bank deposits. These instruments are used in varying combinations to influence overall economic growth and the distribution of credit, bank loans, investments and deposits. Their use also affects interest rates charged on loans or paid on deposits.

The monetary policies and regulations of the Federal Reserve Board have had a significant effect on the operating results of financial institutions in the past and are expected to continue to do so in the future. The effects of such policies upon our business, financial condition and results of operations cannot be predicted.

We are subject to stringent capital requirements, which may adversely impact our return on equity, require us to raise additional capital, or limit our ability to pay dividends or repurchase shares.

Federal regulations establish minimum capital requirements for insured depository institutions, including minimum risk-based capital and leverage ratios, and define “capital” for calculating these ratios. The minimum capital requirements are: (1) a common equity Tier 1 capital ratio of 4.5%; (2) a Tier 1 to risk-based assets capital ratio of 6%; (3) a total capital ratio of 8%; and (4) a Tier 1 leverage ratio of 4%. The regulations also establish a “capital conservation buffer” of 2.5%, which results in the following minimum ratios: (1) a common equity Tier 1 capital ratio of 7.0%; (2) a Tier 1 to risk-based assets capital ratio of 8.5%; and (3) a total capital ratio of 10.5%. An institution will be subject to limitations on paying dividends, engaging in share repurchases and paying discretionary bonuses if its capital level falls below the capital conservation buffer amount.

The application of these capital requirements could, among other things, result in lower returns on equity, and result in regulatory actions if we are unable to comply with such requirements. Specifically, following the completion of the offering, Needham Bank’s ability to pay dividends to NB Bancorp will be limited if it does not maintain the capital conservation buffer required by the capital rules, which may limit NB Bancorp’s ability to pay dividends to its stockholders. See “Supervision and Regulation – Banking Regulation – Capital Requirements.”

We are an emerging growth company, and any decision on our part to comply only with certain reduced reporting and disclosure requirements applicable to emerging growth companies could make our common stock less attractive to investors.

NB Bancorp is an emerging growth company, and we expect we will cease to be an emerging growth company at the end of the fiscal year following the fifth anniversary of the completion of the offering. For as long as we continue to be an emerging growth company, we may choose to take advantage of exemptions from various reporting requirements applicable to other public companies, including, but not limited to, reduced disclosure obligations regarding executive compensation in our periodic reports and proxy statements, and exemptions from the requirements of holding a non-binding advisory vote on executive compensation and shareholder approval of any golden parachute payments not previously approved. We have also elected to use the extended transition period to delay adoption of new or revised accounting pronouncements applicable to public companies until such pronouncements are made applicable to private companies. Accordingly, our financial statements may not be comparable to the financial statements of public companies that comply with such new or revised accounting standards. Investors may find our common stock less attractive since we have chosen to rely on these exemptions. If some investors find our common stock less attractive as a result of any choices to reduce future disclosure, there may be a less active trading market for our common stock and the price of our common stock may be more volatile.

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If our deposits grow too large, we may lose the benefits of excess deposit insurance provided by the Depositors Insurance Fund.

The deposits of Needham Bank are insured in full beyond federal deposit insurance coverage limits by the Depositors Insurance Fund, or the DIF, a private excess deposit insurer created under Massachusetts law. We believe offering full deposit insurance gives us a competitive advantage for individual, corporate and municipal depositors having deposit balances in excess of FDIC insurance limits.  However, the DIF may require member institutions that pose greater than normal loss exposure risk to the DIF to take certain risk-mitigating measures or withdraw from the DIF and become a Massachusetts trust company by operation of law, subject to the Commissioner’s approval.  In such an event, an institution may be required to reduce its level of excess deposits, pay for the reinsurance of excess deposits, make an additional capital contribution to the DIF, provide collateral or take other risk-mitigating measures that the DIF may require, which may include entering into reciprocal deposit programs with other financial institutions or reciprocal deposit services. Reducing excess deposits by taking any of the above risk-mitigating measures, which allows deposits to run off, reduces our overall level of deposits and increases the extent to which we may need to rely in the future on other, more expensive or less stable sources for funding, including FHLB advances, which would reduce net income. Shifting excess deposits into reciprocal deposit programs may result in higher funding costs, which also would reduce net income.

The Federal Reserve Board may require us to commit capital resources to support our bank subsidiary.

Federal law requires that a holding company act as a source of financial and managerial strength to its subsidiary bank and to commit resources to support such subsidiary bank. Under the “source of strength” doctrine, the Federal Reserve Board may require a holding company to make capital injections into a troubled subsidiary bank and may charge the holding company with engaging in unsafe and unsound practices for failure to commit resources to a subsidiary bank. A capital injection may be required at times when the holding company may not have the resources to provide it and therefore may be required to borrow the funds or raise capital. Thus, any borrowing or funds needed to raise capital required to make a capital injection becomes more difficult and expensive and could have an adverse effect on our business, financial condition and results of operations.

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We may become subject to enforcement actions even though noncompliance was inadvertent or unintentional.

The financial services industry is subject to intense scrutiny from bank supervisors in the examination process and aggressive enforcement of federal and state regulations, particularly with respect to mortgage-related practices and other consumer compliance matters, and compliance with anti-money laundering, Bank Secrecy Act and Office of Foreign Assets Control regulations, and economic sanctions against certain foreign countries and nationals. Enforcement actions may be initiated for violations of laws and regulations and unsafe or unsound practices. We maintain systems and procedures designed to ensure that we comply with applicable laws and regulations; however, some legal/regulatory frameworks provide for the imposition of fines or penalties for noncompliance even though the noncompliance was inadvertent or unintentional and even though there was in place at the time systems and procedures designed to ensure compliance. Failure to comply with these and other regulations, and supervisory expectations related thereto, may result in fines, penalties, lawsuits, regulatory sanctions, reputation damage, or restrictions on our business.

We face significant legal risks, both from regulatory investigations and proceedings and from private actions brought against us.

As a participant in the financial services industry, many aspects of our business involve substantial risk of legal liability. From time to time, customers and others make claims and take legal action pertaining to the performance of our responsibilities. Whether customer claims and legal action related to the performance of our responsibilities are founded or unfounded, if such claims and legal actions are not resolved in a manner favorable to us, they may result in significant expenses, attention from management and financial liability. Any financial liability or reputational damage could have a material adverse effect on our business, which, in turn, could have a material adverse effect on our financial condition and results of operations. There is no assurance that litigation with private parties will not increase in the future. Actions currently pending against us may result in judgments, settlements, fines, penalties or other results adverse to us, which could materially adversely affect our business, financial condition or results of operations, or cause serious reputational harm to us.

Risks Related to our Business Strategy

Our business strategy includes growth, and our financial condition and results of operations could be negatively affected if we fail to grow or fail to manage our growth effectively. Growing our operations could also cause our expenses to increase faster than our revenues.

Our business strategy includes growth in assets, deposits and the scale of our operations. Achieving such growth will require us to attract customers that currently bank at other financial institutions in our market area. Our ability to successfully grow will depend on a variety of factors, including our ability to attract and retain experienced bankers, the continued availability of desirable business opportunities and the level of competition from other financial institutions. Growth opportunities may not be available or we may not be able to manage our growth successfully. If we do not manage our growth effectively, our financial condition and operating results could be negatively affected. Furthermore, there can be considerable costs involved in expanding lending capacity, and generally a period of time is required to generate the necessary revenues to offset these costs, especially in areas in which we do not have an established presence. Accordingly, any such business expansion can be expected to negatively impact our earnings until certain economies of scale are reached.

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Our continued pace of growth may require us to raise additional capital in the future, but that capital may not be available when it is needed.

We are required by banking regulatory authorities to maintain adequate levels of capital to support our operations.  We may at some point need to raise additional capital to support our continued growth. If we raise capital through the issuance of additional shares of our common stock or other securities, it would dilute the ownership interests of stockholders and may dilute the per share book value of our common stock. New investors may also have rights, preferences and privileges senior to our current stockholders, which may adversely impact our current stockholders. Also, the need to raise additional capital may force our management to spend more time in managerial and financing-related activities than in operational activities.

Our ability to raise additional capital, if needed, will depend on conditions in the capital markets at that time, which are outside of our control, and on our financial performance. Accordingly, we may not be able to raise additional capital, if needed, with favorable terms. If we cannot raise additional capital when needed, our ability to further expand our operations through internal growth and acquisitions could be materially impaired.

We depend on our management team to implement our business strategy and execute successful operations and we could be harmed by the loss of their services.

We depend on the services of the members of our senior management team who direct our strategy and operations. Our executive officers and lending personnel possess substantial expertise, extensive knowledge of our markets and key business relationships. Any one of them could be difficult to replace. Additionally, in recent years, we have grown our Structured Finance loan portfolio largely through lending relationships to cannabis, wind and solar companies. These industries can entail unique regulatory and operational risks and we believe we have experienced team members who are able to understand and assess these risks when originating and managing these relationships. Our loss of these persons, or our inability to hire additional qualified personnel, could impact our ability to implement our business strategy and could have a material adverse effect on our results of operations and our ability to compete in our markets. See “Management of NB Bancorp.”

Development of new products and services may impose additional costs on us and may expose us to increased operational risk.

The introduction of new products and services can entail significant time and resources, including regulatory approvals. Substantial risks and uncertainties are associated with the introduction of new products and services, including technical and control requirements that may need to be developed and implemented, rapid technological change in the industry, our ability to access technical and other information from its clients, the significant and ongoing investments required to bring new products and services to market in a timely manner at competitive prices and the preparation of marketing, sales and other materials that fully and accurately describe the product or service and its underlying risks. Our failure to manage these risks and uncertainties also exposes it to enhanced risk of operational lapses which may result in the recognition of financial statement liabilities. Regulatory and internal control requirements, capital requirements, competitive alternatives, vendor relationships and shifting market preferences may also determine if such initiatives can be brought to market in a manner that is timely and attractive to our clients. Products and services relying on internet and mobile technologies may expose us to fraud and cybersecurity risks. Failure to successfully manage these risks in the development and implementation of new products or services could have a material adverse effect on our business and reputation, as well as on its consolidated results of operations and financial condition.

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Risks Related to Competitive Matters

Strong competition within our market area may limit our growth and profitability.

Competition in the banking and financial services industry is intense. We compete with commercial banks, savings institutions, mortgage brokerage firms, credit unions, finance companies, mutual funds, insurance companies, brokerage and investment banking firms, financial technology or “fintech companies,” and unregulated or less regulated non-banking entities. Many of these competitors are substantially larger than we are and have substantially greater resources and higher lending limits than we have and offer certain services that we do not or cannot provide. In addition, some of our competitors offer loans with lower interest rates and/or more attractive terms than loans we offer. Competition also makes it increasingly difficult and costly to attract and retain qualified employees. We expect competition to increase in the future as a result of legislative, regulatory and technological changes and the continuing trend of consolidation in the financial services industry. Our profitability depends upon our continued ability to successfully compete for business and qualified employees in our market areas. The greater resources and deposit and loan products offered by some of our competitors may limit our ability to increase our interest-earning assets.

Risks Related to Operational Matters

We face significant operational risks because of our reliance on technology. Our information technology systems may be subject to failure, interruption or security breaches.

Information technology systems are critical to our business. Our business requires us to collect, process, transmit and store significant amounts of confidential information regarding our customers, employees and our own business, operations, plans and business strategies. We use various technology systems to manage our customer relationships, general ledger, investments, deposits, and loans. Our computer systems, data management and internal processes, as well as those of third parties, are integral to our performance. Our operational risks include the risk of malfeasance by employees or persons outside our company, errors relating to transaction processing and technology, systems failures or interruptions, breaches of our internal control systems and compliance requirements, and business continuation and disaster recovery. There have been increasing efforts by third parties to breach data security at financial institutions. Such attacks include computer viruses, malicious or destructive code, phishing attacks, denial of service or information or other security breaches that could result in the unauthorized release, gathering, monitoring, misuse, loss or destruction of confidential, proprietary and other information, damages to systems, or other material disruptions to network access or business operations. We have established policies and procedures to prevent or limit the impact of system failures, interruptions and security breaches, including privacy breaches and cyber-attacks. Although we take protective measures and believe that we have not experienced any of the data breaches described above, the security of our computer systems, software, and networks may be vulnerable to breaches, unauthorized access, misuse, computer viruses, or other malicious code and cyber-attacks that could have an impact on information security. Because the techniques used to cause security breaches change frequently, we may be unable to proactively address these techniques or to implement adequate preventative measures.

In the event of a breakdown in our internal control systems, improper operation of systems or improper employee actions, or a breach of our security systems, including if confidential or proprietary information were to be mishandled, misused or lost, we could suffer financial loss, loss of customers and damage to our reputation, and face regulatory action or civil litigation. Any of these events could have a material adverse effect on our financial condition and results of operations. Insurance coverage may not be available for such losses, or where available, such losses may exceed insurance limits.

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We outsource critical operations to third-party service providers. Systems failures, interruptions and cybersecurity breaches could have a material adverse effect on us.

We outsource a majority of our data processing requirements to third-party providers. Accordingly, our operations are exposed to the risk that these vendors will not perform in accordance with our contractual agreements with them, or we also could be adversely affected if such an agreement is not renewed by the third-party vendor or is renewed on terms less favorable to us. If our third-party providers encounter difficulties, or if we have difficulty communicating with those service providers, our ability to adequately process and account for transactions could be affected, and our business operations could be adversely affected, which could have a material adverse effect on our financial condition and results of operations. Threats to information security also exist in the processing of customer information through various other vendors and their personnel, and our third-party service providers may be vulnerable to unauthorized access, computer viruses, phishing schemes and other security breaches. We may have to expend additional resources to protect against the threat of such security breaches and computer viruses, or to alleviate problems caused by such security breaches or viruses. To the extent that the activities of our third-party service providers or the activities of our customers involve the storage and transmission of confidential information, security breaches and viruses could expose us to claims, regulatory scrutiny, litigation costs and other possible liabilities. To our knowledge, the services and programs provided to us by third parties have not experienced any material security breaches. However, the existence of cyber-attacks or security breaches at third parties with access to our data, such as vendors, may not be disclosed to us in a timely manner.

Our business may be adversely affected by an increasing prevalence of fraud and other financial crimes.

Our loans to businesses and individuals and our deposit relationships and related transactions are subject to exposure to the risk of loss due to fraud and other financial crimes. Nationally, reported incidents of fraud and other financial crimes have increased. To our knowledge, we have not experienced material losses due to apparent fraud or other financial crimes.  While we have policies and procedures designed to prevent such losses, losses may still occur.

We participate in a multiple employer defined benefit pension plan for the benefit of certain of our employees. We may determine to withdraw from this plan in the future. We could incur a substantial expense in connection with the withdrawal, which would negatively affect our income during the year of withdrawal.

We participate in a multiple employer defined benefit pension plan for the benefit of employees of Needham Bank who were employees prior to April 1, 2018, the date on which we froze the future accrual of benefits under this plan. We may choose to withdraw from the plan in the future. The cost to withdraw from the plan is primarily dependent on the value of the plan’s assets and applicable interest rates at the time of any such withdrawal. We cannot estimate the actual costs associated with a potential withdrawal from the plan until the date of the withdrawal, but if these costs were material, it will negatively impact future earnings in the year of withdrawal.

Risks Related to Accounting Matters

Changes in management’s estimates and assumptions may have a material impact on our consolidated financial statements and our financial condition or operating results.

In preparing this prospectus, as well as periodic reports we will be required to file under the Exchange Act, including our consolidated financial statements, our management is and will be required under applicable rules and regulations to make estimates and assumptions as of a specified date. These estimates and assumptions are based on management’s best estimates and experience as of that date and are subject to substantial risk and uncertainty. Materially different results may occur as circumstances change and additional information becomes known. The area requiring significant estimates and assumptions by management include our evaluation of the adequacy of our allowance for credit losses.

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Changes in accounting standards could affect reported earnings.

The regulatory bodies responsible for establishing accounting standards, including the Financial Accounting Standards Board, the SEC and other regulatory bodies, periodically change the financial accounting and reporting guidance that governs the preparation of our financial statements. These changes can be hard to predict and can materially impact how we record and report our financial condition and results of operations. In some cases, we could be required to apply new or revised guidance retroactively.

Other Risks Related to Our Business

We operate as a community bank and our ability to maintain our reputation, which is critical to the success of our business, may materially adversely affect our performance.

We are a community bank, and our reputation is one of the most valuable components of our business. A key component of our business strategy is to rely on our reputation for customer service and knowledge of local markets to expand our presence by capturing new business opportunities from existing and prospective customers in our market area and contiguous areas. Threats to our reputation can come from many sources, including adverse sentiment about financial institutions generally, unethical practices, employee misconduct, failure to deliver minimum standards of service or quality, compliance deficiencies, cybersecurity incidents and questionable or fraudulent activities of our customers. Negative publicity regarding our business, employees, or customers, with or without merit, may result in the loss of customers and employees, costly litigation and increased governmental regulation, any or all of which could adversely affect our business and operating results.

The cost of additional finance and accounting systems, procedures and controls in order to satisfy our new public company reporting requirements will increase our expenses.

As a result of the completion of the offering, we will become a public reporting company. The obligations of being a public company, including the substantial public reporting obligations, will require significant expenditures and place additional demands on our management team. We will make changes to our internal controls and procedures for financial reporting and accounting systems to meet our reporting obligations as a public company. Any failure to achieve and maintain an effective internal control environment could have a material adverse effect on our business and stock price. In addition, we may need to hire additional compliance, accounting and financial staff with appropriate public company experience and technical knowledge, and we may not be able to do so in a timely fashion. As a result, we may need to rely on outside consultants to provide these services for us until qualified personnel are hired. These obligations will increase our operating expenses and could divert our management’s attention from our operations.

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Societal responses to climate change could adversely affect our business and performance, including indirectly through impacts on our customers.

Concerns over the long-term impacts of climate change have led and will continue to lead to governmental efforts around the world to mitigate those impacts. Consumers and businesses also may change their behavior as a result of these concerns. We and our customers will need to respond to new laws and regulations as well as consumer and business preferences resulting from climate change concerns. The impact on our customers will likely vary depending on their specific attributes, including reliance on or role in carbon intensive activities. Among the impacts to us could be a drop in demand for our products and services, particularly in certain sectors. In addition, we could face reductions in creditworthiness on the part of some customers or in the value of assets securing loans. Our efforts to take these risks into account in making lending and other decisions, including by increasing our business with climate-friendly companies, may not be effective in protecting us from the negative impact of new laws and regulations or changes in consumer or business behavior.

Risks Related to the Offering

The future price of our common stock may be less than the purchase price in the offering.

If you purchase shares of common stock in the stock offering, you may not be able to sell them at or above the purchase price in the offering. The purchase price in the offering is based upon an independent third-party appraisal of the pro forma market value of NB Bancorp. The appraisal is not intended, and should not be construed, as a recommendation of any kind as to the advisability of purchasing shares of our common stock, and such appraisal is based on certain estimates, assumptions and projections, all of which are subject to change from time to time. Our aggregate pro forma market value as reflected in the final independent appraisal may exceed the market price of our shares of common stock after the completion of the offering, which may result in our stock trading below the initial offering price of $10.00 per share.

After the shares of our common stock begin trading, the trading price of the common stock will be determined by the marketplace, and will be influenced by many factors outside of our control, including prevailing interest rates, investor perceptions, securities analyst research reports and general industry, geopolitical and economic conditions. Publicly traded stocks, including stocks of financial institutions, often experience substantial market price volatility. Price fluctuations in our common stock may be unrelated to our operating performance.

We have broad discretion in using the net proceeds of the stock offering. Our failure to effectively deploy the net proceeds of the offering may have an adverse effect on our financial performance and the value of our common stock.

We intend to invest between $128.6 million and $174.6 million of the net proceeds of the offering (or $201.0 million at the adjusted maximum of the offering range) in Needham Bank. We also expect to use a portion of the net proceeds to make a cash contribution to our charitable foundations and fund a loan for the purchase of shares of common stock in the offering by our ESOP. We may use the remaining net proceeds (if any) to invest in short-term and other investments and for other general corporate purposes, including the repurchase of shares of our common stock. Needham Bank intends to use the net proceeds it receives to fund new loans, enhance existing products and services, invest in securities, or for other general corporate purposes. However, with the exception of the loan to the ESOP and the contribution to the charitable foundation, we have not allocated specific amounts of the net proceeds for any of these purposes, and we will have significant flexibility in determining the amount of the net proceeds we apply to different uses and when we apply or reinvest such proceeds. We have not established a timetable for investing the net proceeds, and, accordingly, we may not invest the net proceeds at a time that is most beneficial to NB Bancorp, Needham Bank or our stockholders. For additional information see “How We Intent to Use the Proceed From the Offering.”

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There may be a limited trading market in our common stock, which would hinder your ability to sell our common stock and may lower the market price of the stock.

We have never issued capital stock and there is no established market for our common stock. We expect that our common stock will be traded on the Nasdaq Capital Market, subject to completion of the offering and compliance with certain conditions. Piper Sandler & Co. has advised us that it intends to make a market in our common stock following the offering, but it is under no obligation to do so or to continue to do so once trading begins. The development of an active trading market depends on the existence of willing buyers and sellers, the presence of which is not within our control, or that of any market maker. The number of active buyers and sellers of the shares of common stock at any particular time may be limited. Under such circumstances, you could have difficulty selling your shares of common stock on short notice, and, therefore, you should not view the shares of common stock as a short-term investment. If you purchase shares of common stock, you may not be able to sell them at or above $10.00 per share. Purchasers of common stock in this stock offering should have long-term investment intent and should recognize that there may be a limited trading market in the common stock. This may make it difficult to sell the common stock after the stock offering and may have an adverse impact on the price at which the common stock can be sold.

The capital we raise in the stock offering may negatively impact our return on equity until we can fully implement our business plan. This could negatively affect the trading price of our shares of common stock.

Net income divided by average equity, known as “return on equity,” is a ratio many investors use to compare the performance of a financial institution to its peers. Our return on equity may be relatively low until we are able to implement our business plan and leverage the additional capital we receive from the offering. Although we anticipate increasing net interest income using proceeds of the offering, our return on equity will be reduced by the capital raised in the offering, higher expenses from the costs of being a public company, and added expenses associated with our ESOP and the stock-based benefit plan we intend to adopt. Until we can implement our business plan and increase our net interest income through investment of the proceeds of the offering, our return on equity may remain relatively low compared to our peer group, which may reduce the value of our shares.

Our stock-based benefit plans will increase our expenses, which will reduce our net income.

We intend to implement a stock-based benefit plan after the offering, subject to shareholder approval, which would increase our annual compensation and benefit expenses related to stock options and stock awards granted to participants under the stock-based benefit plan. The amount of these stock-related compensation and benefit expenses would depend on the number of options and stock awards granted, the fair value of the options and our stock on the date of grant, the vesting period, and other factors that we cannot predict at this time. If we implement stock-based benefit plan within one year following the completion of the offering, the total shares of common stock reserved for issuance pursuant to awards of restricted stock and grants of options under such plan would be limited to 4% and 10%, respectively, of the shares of our common stock issued in the offering, including shares contributed to the charitable foundation. If we adopt a stock-based benefit plan more than 12 months after the completion of the conversion, any such plan could allow for greater amounts of awards and options and, therefore, we could award restricted shares of common stock or grant options in excess of these amounts, which would further increase costs.

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We anticipate that our ESOP will purchase 8% of the shares of common stock issued in the offering, including shares contributed to the charitable foundation. The cost of acquiring the shares of common stock for the ESOP is estimated to be between $22.0 million at the minimum of the offering range and $34.2 million at the adjusted maximum of the offering range (assuming we are able to purchase all of such shares in the offering). We will record annual ESOP expenses in an amount equal to the fair value of shares of common stock committed to be released to employees. If shares of common stock appreciate in value over time, compensation expense relating to the ESOP will increase.

The estimated expense in the first year following the offering for shares purchased in the offering (or in the after-market if the offering is oversubscribed by the eligible account holders) by our ESOP and for a stock-based benefit plan implemented within one year after the offering, subject to receipt of shareholder approval, is approximately $9.4 million ($7.0 million after tax) at the adjusted maximum of the offering range as set forth in the pro forma financial information under “Pro Forma Data,” assuming the $10.00 per share offering price as fair market value. Actual expense may be higher if the price of our common stock at the time the shares are allocated or awarded is greater than $10.00 per share. For further discussion of our proposed stock-based plans, see “Management – Benefits to be Considered Following Completion of the Stock Offering.”

The implementation of a stock-based benefit plan is likely to dilute your ownership interest.

We intend to adopt one or more new stock-based benefit plans following the offering. These plans may be funded either through open market purchases of our common stock or from the issuance of authorized but unissued shares of common stock. Our ability to repurchase shares of our common stock to fund these plans will be subject to many factors, including applicable regulatory restrictions on stock repurchases, the availability of stock in the market, the trading price of our stock, our capital levels, alternative uses for our capital and our financial performance. While our intention is to fund the new stock-based benefit plans through open market purchases, stockholders would experience a 9.09% dilution in ownership interest if newly issued shares of our common stock are used to fund stock options in an amount equal to 10% of the sum of shares sold in the offering and contributed to the charitable foundation, and all such stock options are exercised, and a 3.85% dilution in ownership interest if newly issued shares of our common stock are used to fund grants of restricted common stock in an amount equal to 4% of the sum of shares sold in the offering and contributed to the charitable foundation. Such dilution would also reduce earnings per share. If we adopt the plans more than 12 months following the conversion, new stock-based benefit plans would not be subject to these size limitations and stockholders could experience even greater dilution.

Although the implementation of new stock-based benefit plans would be subject to stockholder approval, historically, the overwhelming majority of stock-based benefit plans adopted by savings institutions and their holding companies following mutual-to-stock conversions have been approved by stockholders.

We have not determined the timing of the adoption of stock-based benefit plan following the offering. Stock-based benefit plans adopted more than one year following the completion of the offering may exceed regulatory restrictions on the size of stock-based benefit plans adopted within one year, which would increase our expenses and the dilution to other stockholders.

If we adopt stock-based benefit plans more than 12 months following the completion of the conversion, then grants of shares of common stock or stock options under our proposed stock-based benefit plans may exceed 4% and 10%, respectively, of the sum of shares of common stock sold in the offering and contributed to the charitable foundation. Stock-based benefit plans that provide for awards in excess of these amounts would increase our costs beyond the amounts estimated in “– Our stock-based benefit plans will increase our expenses and reduce our income.” Stock-based benefit plans that provide for awards in excess of these amounts could also result in dilution to stockholders in excess of that described in “– The implementation of stock-based benefit plans may dilute your ownership interest. Historically, stockholders have approved these stock-based benefit plans.” Although the implementation of stock-based benefit plans would be subject to stockholder approval, the timing of the implementation of such plans will be at the discretion of our board of directors.

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Various factors may make takeover attempts more difficult to achieve.

Certain provisions of our articles of incorporation and bylaws and federal and state banking laws, including regulatory approval requirements, could make it more difficult for a third party to acquire control of NB Bancorp without our board of directors’ approval. Massachusetts and federal regulations applicable to the conversion state that for a period of three years following completion of the conversion, no person may offer to acquire or acquire beneficial ownership of more than 10% of our common stock without prior approval of the Federal Reserve Board. Under federal law, subject to certain exemptions, a person, entity or group must notify the Federal Reserve Board and receive the Federal Reserve Board’s non-objection before acquiring control of a bank holding company. There also are provisions in our articles of incorporation and bylaws that we may use to delay or block a takeover attempt, including a provision that prohibits any person from voting more than 10% of our outstanding shares of common stock. Furthermore, shares of restricted stock and stock options that we may grant to employees and directors, stock ownership by our management and directors and other factors may make it more difficult for companies or persons to acquire control of NB Bancorp without the consent of our board of directors, and may increase the cost of an acquisition. Taken as a whole, these statutory or regulatory provisions and provisions in our articles of incorporation and bylaws could result in NB Bancorp being less attractive to a potential acquirer and therefore could adversely affect the market price of our common stock. For additional information, see “Restrictions on Acquisition of NB Bancorp” and “Management of NB Bancorp – Benefits to be Considered Following Completion of the Conversion.”

Our articles of incorporation provide that, subject to limited exception, state and federal courts in the State of Maryland are the sole and exclusive forum for certain stockholder litigation matters, which could limit our stockholders’ ability to obtain a favorable judicial forum for disputes with us or our directors, officers, and other employees.

The articles of incorporation of NB Bancorp provide that, unless NB Bancorp consents in writing to the selection of an alternative forum, the sole and exclusive forum for (i) any derivative action or proceeding brought on behalf of NB Bancorp, (ii) any action asserting a claim of breach of a fiduciary duty owed by any director, officer or other employee of NB Bancorp to NB Bancorp or its stockholders, (iii) any action asserting a claim arising pursuant to any provision of the Maryland General Corporation Law, or (iv) any action asserting a claim governed by the internal affairs doctrine will be conducted in a state or federal court located within the State of Maryland, in all cases subject to the court having personal jurisdiction over the indispensable parties named as defendants. This exclusive forum provision does not apply to claims arising under the federal securities laws. This exclusive forum provision may limit a stockholder’s ability to bring a claim in a judicial forum it finds favorable for disputes with NB Bancorp and its directors, officers, and other employees or may cause a stockholder to incur additional expense by having to bring a claim in a judicial forum that is distant from where the stockholder resides, or both. In addition, if a court were to find this exclusive forum provision to be inapplicable or unenforceable in a particular action, we may incur additional costs associated with resolving the action in another jurisdiction, which could have a material adverse effect on our financial condition and results of operations.

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You may not revoke your decision to purchase NB Bancorp common stock in the subscription or community offerings after you send us your order.

Funds submitted or automatic withdrawals authorized in connection with the purchase of shares of common stock in the subscription and community offerings will be held by us until the completion or termination of the offering, including any extension of the expiration date and consummation of a syndicated offering. Because completion of the offering will be subject to regulatory approvals and an update of the independent appraisal prepared by RP Financial, among other factors, there may be one or more delays in completing the offering. Orders submitted in the subscription and community offerings are irrevocable, and purchasers will have no access to their funds unless the offering is terminated, or extended beyond December 29, 2023, or the number of shares to be sold in the offering is increased to more than 40,997,500 shares or decreased to fewer than 26,350,000 shares.

The distribution of subscription rights could have adverse income tax consequences.

If the subscription rights granted in connection with the offering are deemed to have an ascertainable value, receipt of such rights may be taxable in an amount equal to such value. Whether subscription rights are considered to have ascertainable value is an inherently factual determination. We have received an opinion of counsel, Luse Gorman, PC, that it is more likely than not that such rights have no value; however, such opinion is not binding on the Internal Revenue Service.

Risks Related to Our Contribution to the Charitable Foundations

The contribution to the charitable foundation will dilute your ownership interest and adversely affect net income in the year in which we consummate the conversion.

We intend to establish and fund a new charitable foundation in connection with the conversion and offering. We intend to contribute $2.0 million in cash and a number of shares of our common stock equal to 4% of the shares that will be outstanding immediately after this contribution. Assuming the sale of 31,000,000 shares at the midpoint of the offering range, we would contribute $2.0 million in cash and 1,291,667 shares to the charitable foundation. The contribution will have an adverse effect on our net income for the quarter and year in which we make the issuance and contribution to the charitable foundation. Assuming the sale of 31,000,000 shares at the midpoint of the offering range, the after-tax expense of the contribution is expected to reduce net income in the year of the contribution by approximately $10.9 million.

Our contribution to the charitable foundation may not be tax deductible, which could reduce our profits.

We may not have sufficient profits to be able to fully use the tax deduction from our contribution to the charitable foundation. Under the Internal Revenue Code, an entity is permitted to deduct up to 10% of its taxable income (generally income before federal income taxes and charitable contributions expense) in any one year for charitable contributions. Any contribution in excess of the 10% limit may be deducted for federal income tax purposes over each of the five years following the year in which the charitable contribution is made. Accordingly, a charitable contribution could, if necessary, be deducted over a six-year period and expires thereafter. Our contribution to the charitable foundation will result in the creation of a deferred tax asset. We will assess at least annually whether it is more likely than not that all or a portion of the deferred tax assets will be realized, taking into account projections of future taxable income during the relevant periods. If we conclude that it is more likely than not that a portion of the deferred tax asset will not be realized, we would establish a valuation allowance, which would be a charge against earnings in the year in which the allowance is established.

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SELECTED FINANCIAL AND OTHER DATA

The following tables set forth selected consolidated historical financial and other data of Needham Bank for the years and at the dates indicated. This information is derived in part from, and should be read together with, the audited consolidated financial statements and notes thereto of Needham Bank beginning at page F-1 of this prospectus. The following information is only a summary, and should be read in conjunction with our consolidated financial statements and notes beginning on page F-1 of this prospectus.

	At June 30,		At December 31,
	2023		2022		2021
	(In thousands)
Selected Financial Condition Data:
Total assets	$	4,028,617	$	3,592,335	$	2,922,671
Cash and cash equivalents		113,520		156,545		467,050
Investment securities available for sale		213,977		245,480		259,750
Loans, net of allowance for credit losses		3,490,041		2,990,417		2,086,341
Banking premises and equipment, net		35,982		35,344		29,208
Bank-owned life insurance		49,749		49,006		25,651
Prepaid expenses and other assets		61,850		57,167		26,452
Deposits		3,261,671		2,886,743		2,564,538
Accrued expenses and other liabilities		55,500		52,399		20,188
Equity		356,973		344,065		326,129

	For the Six Months Ended				For the Years Ended
	June 30,				December 31,
	2023		2022		2022		2021
	(In thousands)
Selected Operating Data:
Interest income	$	97,366	$	49,374	$	120,512	$	90,641
Interest expense		35,306		3,818		15,548		12,630
Net interest income		62,060		45,556		104,964		78,011
Provision for credit losses		6,019		1,250		6,700		2,050
Net interest income after provision for credit losses		56,041		44,306		98,264		75,961
Non-interest income		9,179		4,667		9,275		8,654
Non-interest expense		44,784		34,381		71,151		56,983
Income before income taxes		20,436		14,592		36,388		27,632
Income tax expense		5,459		3,649		6,323		6,057
Net income	$	14,977	$	10,943	$	30,065	$	21,575

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	At or For the Six Months Ended June 30,						At or For the Years Ended December 31,
	2023			2022			2022			2021
Performance Ratios:
Return on average assets (1)		0.81	%		0.74	%		0.96	%		0.76	%
Return on average equity (1)		8.51	%		6.70	%		9.06	%		6.82	%
Interest rate spread (2)		2.96	%		3.09	%		3.33	%		2.69	%
Net interest margin (1) (3)		3.51	%		3.18	%		3.49	%		2.81	%
Non-interest expense to average assets (1)		2.41	%		2.31	%		2.28	%		2.00	%
Efficiency ratio (4)		62.7	%		68.5	%		62.3	%		65.8	%
Average interest-earning assets to average interest-bearing liabilities		127.5	%		132.2	%		132.2	%		126.5	%
Capital Ratios:
Community bank leverage ratio		9.62	%		10.96	%		10.49	%		11.23	%
Average equity to average assets		9.47	%		10.99	%		10.64	%		11.11	%
Asset Quality Ratios:
Allowance for credit losses as a percentage of total loans		0.89	%		0.83	%		0.83	%		0.88	%
Allowance for credit losses as a percentage of non-performing loans		235	%		206	%		192	%		307	%
Net (charge-offs) recoveries to average outstanding loans during the period (1)		(0.05	)%		0.00	%		0.00	%		(0.16	)%
Non-performing loans as a percentage of total loans		0.38	%		0.40	%		0.43	%		0.29	%
Non-performing loans as a percentage of total assets		0.33	%		0.32	%		0.36	%		0.21	%
Total non-performing assets as a percentage of total assets		0.33	%		0.32	%		0.36	%		0.21	%
Other:
Number of offices		13			12			13			12
Number of full-time equivalent employees		330			292			307			257

(1) Annualized where appropriate.

(2) Represents the difference between the weighted average yield on interest-earning assets and the weighted average cost of interest-bearing liabilities.

(3) Represents net interest income as a percentage of average interest-earning assets.

(4) Represents noninterest expenses divided by the sum of net interest income and noninterest income.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus contains forward-looking statements, which can be identified by the use of words such as “estimate,” “project,” “believe,” “intend,” “anticipate,” “assume,” “plan,” “seek,” “expect,” “will,” “may,” “should,” “indicate,” “would,” “believe,” “contemplate,” “continue,” “intend,” “target” and words of similar meaning. These forward-looking statements include, but are not limited to:

· statements of our goals, intentions and expectations;

· statements regarding our business plans, prospects, growth and operating strategies;

· statements regarding the quality of our loan portfolio; and

· estimates of our risks and future costs and benefits.

These forward-looking statements are based on our current beliefs and expectations and are inherently subject to significant business, economic and competitive uncertainties and contingencies, many of which are beyond our control. In addition, these forward-looking statements are subject to assumptions with respect to future business strategies and decisions that are subject to change. We are under no duty to and do not undertake any obligation to update any forward-looking statements after the date of this prospectus.

The following factors, among others, could cause actual results to differ materially from the anticipated results or other expectations expressed in the forward-looking statements:

· general economic conditions, either nationally or in our market areas, that are worse than expected including as a result of employment levels and labor shortages, and the effects of inflation, a potential recession or slowed economic growth caused by supply chain disruptions or otherwise;

· inflation and changes in the interest rate environment that reduce our margins and yields, our mortgage banking revenues, the fair value of financial instruments, including our mortgage servicing rights asset, or our level of loan originations, or increase the level of defaults, losses and prepayments on loans we have made and make;

· changes in the level and direction of loan delinquencies and write-offs and changes in estimates of the adequacy of the allowance for loan and lease losses;

· the effect of any change in federal government enforcement of federal laws affecting the cannabis industry;

· changes in liquidity, including the size and composition of our deposit portfolio, including the percentage of uninsured deposits in the portfolio;

· our ability to access cost-effective funding;

· fluctuations in real estate values and both residential and commercial real estate market conditions;

· demand for loans and deposits in our market area;

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· our ability to implement and change our business strategies;

· competition among depository and other financial institutions;

· adverse changes in the securities or secondary mortgage markets;

· changes in laws or government regulations or policies affecting financial institutions, including changes in regulatory fees, capital requirements and insurance premiums;

· changes in the quality or composition of our loan or investment portfolios;

· technological changes that may be more difficult or expensive than expected;

· the inability of third-party providers to perform as expected;

· a failure or breach of our operational or security systems or infrastructure, including cyberattacks;

· our ability to manage market risk, credit risk and operational risk;

· our ability to enter new markets successfully and capitalize on growth opportunities;

· changes in consumer spending, borrowing and savings habits;

· changes in accounting policies and practices, as may be adopted by the bank regulatory agencies, the Financial Accounting Standards Board, the SEC or the Public Company Accounting Oversight Board;

· our ability to attract and retain key employees; and

· changes in the financial condition, results of operations or future prospects of issuers of securities that we own.

Because of these and a wide variety of other uncertainties, our actual future results may be materially different from the results indicated by these forward-looking statements. Please see “Risk Factors” beginning on page 18.

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HOW WE INTEND TO USE THE PROCEEDS FROM THE OFFERING

Although we cannot determine what the actual net proceeds from the sale of the shares of common stock in the offering will be until the offering is completed, we anticipate that the net proceeds will be between $257.3 million and $349.1 million, or $401.9 million if the offering range is increased to the adjusted maximum. Please see “Pro Forma Data” for additional information.

We intend to distribute the net proceeds from the offering as follows:

	Based Upon the Sale at $10.00 Per Share of
	26,350,000 shares						31,000,000 shares						35,650,000 shares						40,997,500 shares (1)
	Amount			Percent of Net Proceeds			Amount			Percent of Net Proceeds			Amount			Percent of Net Proceeds			Amount			Percent of Net Proceeds
		(Dollars in thousands)
Offering proceeds	$	263,500					$	310,000					$	356,500					$	409,975
Less offering expenses and fees		(6,233	)					(6,808	)					(7,384	)					(8,046	)
Net offering proceeds	$	257,267			100.0	%	$	303,192			100.0	%	$	349,116			100.0	%	$	401,929			100.0	%
Use of net proceeds:
To Needham Bank	$	128,634			50.0	%	$	151,596			50.0	%	$	174,558			50.0	%	$	200,965			50.0	%
To fund loan to ESOP		21,958			8.5	%		25,833			8.5	%		29,708			8.5	%		34,165			8.5	%
Cash contribution to charitable foundation		2,000			0.8	%		2,000			0.7	%		2,000			0.6	%		2,000			0.5	%
Retained by NB Bancorp.	$	104,676			40.7	%	$	123,763			40.8	%	$	142,850			40.9	%	$	164,800			41.0	%

(1) As adjusted to give effect to an increase in the number of shares, which could occur due to a 15% increase in the offering range to reflect demand for the shares or changes in market conditions following the commencement of the offering.

Payments for shares of common stock made through withdrawals from existing deposit accounts will not result in the receipt of new funds for investment but will result in a reduction of Needham Bank’s deposits. The net proceeds may vary because the total expenses relating to the offering may be more or less than our estimates. For example, our expenses would increase if a syndicated community offering were used to sell shares of common stock not purchased in the subscription and community offerings.

NB Bancorp intends to fund a loan to the ESOP to purchase shares of common stock in the stock offering and contribute cash and shares of common stock to our charitable foundation. NB Bancorp may also use the proceeds it retains from the offering:

· to invest in investment securities consistent with our investment policy;

· to pay cash dividends to stockholders;

· to repurchase shares of our common stock; and

· for other general corporate purposes.

With the exception of the funding of the loan to the ESOP and the contribution to our charitable foundation, NB Bancorp has not quantified its plans for use of the offering proceeds for each of the foregoing purposes. Initially, we intend to invest a substantial portion of the net proceeds in shorter term investment securities prior to deploying the proceeds into new loans.

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Under currently applicable regulations, we may not repurchase shares of our common stock during the first year following the conversion, except to fund equity benefit plans other than stock options or except when extraordinary circumstances exist and with prior regulatory approval.

Needham Bank will receive a capital contribution equal to at least 50% of the net proceeds of the offering. Needham Bank may use the net proceeds it receives from the offering:

· to fund new loans;

· to invest in investment securities consistent with our investment policy;

· to pay down existing borrowings and/or reduce our utilization of brokered deposits;

· to expand its banking franchise by establishing targeted de novo branches or acquiring branches from another financial institution, although no such acquisition transactions are contemplated at this time; and

· for other general corporate purposes.

Needham Bank has not quantified its plans for use of the offering proceeds for any of the foregoing purposes. The use of the proceeds outlined above may change based on many factors, including, but not limited to, changes in interest rates, equity markets, laws and regulations affecting the financial services industry, our relative position in the financial services industry, the attractiveness of opportunities to expand our operations through establishing or acquiring new branches, our ability to receive regulatory approval for any such expansion activities, and overall market conditions.

OUR POLICY REGARDING DIVIDENDS

Following completion of the offering, our board of directors will have the authority to declare dividends on our shares of common stock, subject to statutory and regulatory requirements. However, no decision has been made with respect to the payment of dividends. In determining whether to pay a cash dividend and the amount of such cash dividend, the board of directors is expected to take into account a number of factors, including capital requirements, our consolidated financial condition and results of operations, tax considerations, statutory and regulatory limitations and general economic conditions. No assurances can be given that any dividends will be paid or that, if paid, they will not be reduced or eliminated in the future. Special cash dividends, stock dividends or returns of capital, to the extent permitted by applicable law, regulations and policy, may be paid in addition to, or in lieu of, regular cash dividends. We will file a consolidated tax return with Needham Bank. Accordingly, it is anticipated that any cash distributions made by us to our stockholders would be treated as cash dividends and not as a non-taxable return of capital for federal and state tax purposes. Additionally, pursuant to bank conversion regulations, during the three-year period following the offering, we will not take any action to declare an extraordinary dividend to stockholders that would be treated by recipients as a tax-free return of capital for federal income tax purposes.

The dividends we can declare and pay will depend, in part, upon receipt of dividends from Needham Bank, because initially we will have no source of income other than dividends from Needham Bank, earnings from the investment of proceeds from the sale of shares of common stock, and interest payments received in connection with the loan to the ESOP. Applicable regulations impose significant limitations on “capital distributions” by depository institutions. See “Supervision and Regulation – Massachusetts Banking Laws and Supervision – Dividends” and “Supervision and Regulation – Federal Regulation – Capital Requirements.”

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MARKET FOR THE COMMON STOCK

NB Bancorp is a newly formed company which has never publicly issued capital stock, and there is no established market for our shares of common stock. We expect that our shares of common stock will be listed for trading on the Nasdaq Capital Market under the symbol “NBBK” subject to completion of the stock offering and compliance with certain listing conditions, including the presence of at least three registered and active market makers. Piper Sandler & Co. has advised us that it intends to make a market in shares of our common stock following the stock offering, but it is not obligated to do so or to continue to do so once it begins. While we will attempt before completion of the stock offering to obtain commitments from at least two other broker-dealers to make a market in shares of our common stock, there can be no assurance that we will be successful in obtaining such commitments.

The development and maintenance of a public market, having the desirable characteristics of depth, liquidity and orderliness, depends on the existence of willing buyers and sellers, the presence of which is not within our control or that of any market maker. The number of active buyers and sellers of shares of our common stock at any particular time may be limited, which may have an adverse effect on the price at which shares of our common stock can be sold. There can be no assurance that persons purchasing the shares of common stock will be able to sell their shares at or above the $10.00 offering purchase price per share.

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HISTORICAL AND PRO FORMA REGULATORY CAPITAL COMPLIANCE

At June 30, 2023, Needham Bank had opted in, and was in compliance with, the community bank leverage ratio framework. The table below sets forth the historical equity capital and regulatory capital of Needham Bank at June 30, 2023, and the pro forma equity capital and regulatory capital of Needham Bank, after giving effect to the sale of shares of common stock at a $10.00 per share purchase price. The table assumes the receipt by Needham Bank of 50% of the net offering proceeds. See “How We Intend to Use the Proceeds from the Offering.”

	Needham Bank Historical at June 30,					Needham Bank Pro Forma at June 30, 2023 Based Upon the Sale in the Offering of:
	2023					26,350,000 shares						31,000,000 shares						35,650,000 shares						40,997,500 shares (1)
	Amount		Percent of Assets			Amount			Percent of Assets			Amount			Percent of Assets			Amount			Percent of Assets			Amount			Percent of Assets
	(Dollars in thousands)
Equity	$	356,887		8.86	%	$	452,584			10.89	%	$	469,733			11.24	%	$	486,883			11.58	%	$	506,606			11.98	%
Tier 1 leverage capital (2)(3)	$	370,302		9.62	%	$	465,999			11.72	%	$	483,148			12.08	%	$	500,298			12.44	%	$	520,021			12.84	%
Tier 1 leverage requirement		192,376		5.00	%		198,808			5.00	%		199,956			5.00	%		201,104			5.00	%		202,424			5.00	%
Excess	$	177,926		4.62	%	$	267,191			6.72	%	$	283,192			7.08	%	$	299,194			7.44	%	$	317,597			7.84	%
Reconciliation of capital infused into Needham Bank:
Net proceeds						$	128,634					$	151,596					$	174,558					$	200,965
Less: Common stock acquired by ESOP							(21,958	)					(25,833	)					(29,708	)					(34,165	)
Less: Common stock acquired by stock-based incentive plans							(10,979	)					(12,917	)					(14,854	)					(17,082	)
Pro forma increase						$	95,697					$	112,846					$	129,996					$	149,718

(1) As adjusted to give effect to an increase in the number of shares which could occur due to a 15% increase in the offering range to reflect demand for the shares or changes in market conditions following the commencement of the offering.

(2) Leverage capital ratios are shown as a percentage of total adjusted assets.

(3) Pro forma amounts and percentages assume net proceeds are invested in assets that carry a 50% risk weighting.

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CAPITALIZATION

The following table presents the historical consolidated capitalization of NB Financial, MHC at June 30, 2023 and the pro forma consolidated capitalization of NB Bancorp, after giving effect to the conversion and the offering, based upon the assumptions set forth in the “Pro Forma Data” section.

	NB Financial,			Pro Forma at June 30, 2023, Based Upon the Sale in the Offering at $10.00 per Share of
	MHC at June 30, 2023			26,350,000 shares			31,000,000 shares			35,650,000 shares			40,997,500 shares (1)
		(Dollars in thousands)
Deposits (2)	$	3,261,671		$	3,261,671		$	3,261,671		$	3,261,671		$	3,261,671
Borrowings		337,637			337,637			337,637			337,637			337,637
Total deposits and borrowings	$	3,599,308		$	3,599,308		$	3,599,308		$	3,599,308		$	3,599,308
Stockholders’ equity:
Preferred stock $0.01 par value, 5,000,000 shares authorized; none issued or outstanding	$	—		$	—		$	—		$	—		$	—
Common stock $0.01 par value, 120,000,000 shares authorized; assuming shares outstanding as shown (3)		—			274			323			371			427
Additional paid-in capital (4)		—			267,972			315,786			363,599			418,584
Retained earnings (5)		371,325			371,325			371,325			371,325			371,325
Accumulated other comprehensive (loss)		(14,352	)		(14,352	)		(14,352	)		(14,352	)		(14,352	)
Net impact of foundation
Expense of donation to foundation		—			(12,979	)		(14,917	)		(16,854	)		(19,082	)
Tax benefit of donation to foundation		—			3,245			3,729			4,214			4,771
Less:
Common stock to be acquired by ESOP (6)		—			(21,958	)		(25,833	)		(29,708	)		(34,165	)
Common stock to be acquired by stock-based benefit plans (7)		—			(10,979	)		(12,917	)		(14,854	)		(17,082	)
Total stockholders’ equity	$	356,973		$	582,548		$	623,144		$	663,741		$	710,426
Total stockholders’ equity as a percentage of total assets (2)		8.86	%		13.69	%		14.51	%		15.31	%		16.21	%
Pro forma shares outstanding:
Shares offered for sale in offering		—			26,350,000			31,000,000			35,650,000			40,997,500
Shares issued to charitable foundation		—			1,097,917			1,291,667			1,485,417			1,708,229
Total shares outstanding		—			27,447,917			32,291,667			37,135,417			42,705,729

(1) As adjusted to give effect to an increase in the number of shares of common stock that could occur due to a 15% increase in the offering range to reflect demand for shares or changes in market conditions following the commencement of the subscription and community offerings.

(2) Does not reflect withdrawals from deposit accounts for the purchase of shares of common stock in the offering. These withdrawals would reduce pro forma deposits and assets by the amount of the withdrawals.

(3) No effect has been given to the issuance of additional shares of NB Bancorp common stock pursuant to one or more stock-based benefit plans. If these plans are implemented within 12 months following the completion of the offering, an amount up to 10% and 4% of the shares of NB Bancorp common stock sold in the offering, including shares issued to our charitable foundation, will be reserved for issuance upon the exercise of stock options and for issuance as restricted stock awards, respectively. See “Management of NB Bancorp – Benefits to be Considered Following Completion of the Stock Offering.”

(4) The sum of the par value of the total shares outstanding and additional paid-in capital equals the net offering proceeds at the offering price of $10.00 per share before deducting shares issued to the charitable foundation.

(5) The retained earnings of Needham Bank will be substantially restricted after the conversion. See “Our Policy Regarding Dividends,” “The Conversion and Plan of Distribution – Liquidation Rights” and “Supervision and Regulation.”

(6) Assumes that 8% of the shares issued in the conversion (including shares to be contributed to the charitable foundation) will be acquired by the ESOP financed by a loan from NB Bancorp. The loan will be repaid principally from Needham Bank’s contributions to the ESOP. Since NB Bancorp will finance the ESOP debt, this debt will be eliminated through consolidation and no asset or liability will be reflected on NB Bancorp’s consolidated financial statements. Under generally accepted accounting principles, the amount of common stock to be acquired by the ESOP represents unearned compensation. Accordingly, the amount of shares of common stock acquired by the ESOP is shown in this table as a reduction of total stockholders’ equity.

(7) Assumes a number of shares of common stock equal to 4% of the shares of common stock to be issued in the conversion (including shares to be contributed to the charitable foundation) will be purchased for grant by one or more stock-based benefit plans in open market purchases. The dollar amount of common stock to be purchased is based on the $10.00 per share subscription price in the offering and represents unearned compensation, which is presented as a reduction of stockholders’ equity. This amount does not reflect possible increases or decreases in the value of common stock relative to the subscription price in the offering. As NB Bancorp accrues compensation expense to reflect the vesting of shares pursuant to the stock-based benefit plans, the credit to equity will be offset by a charge to non-interest expense. Implementation of the stock-based benefit plans will require stockholder approval. Any funds to be used by the stock-based benefit plans to conduct open market purchases will be provided by NB Bancorp.

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PRO FORMA DATA

The following table summarizes historical data of NB Financial, MHC and pro forma data of NB Bancorp at and for the six months ended June 30, 2023 and at and for the year ended December 31, 2022. This information is based on assumptions set forth below and in the table, and should not be used as a basis for projections of market value of the shares of common stock following the conversion and offering.

The net proceeds in the tables are based upon the following assumptions:

· all shares of common stock will be sold in the subscription or community offerings;

· our ESOP will purchase 8% of the shares of common stock issued in the conversion (including shares contributed to the charitable foundation) with a loan from NB Bancorp. The loan will be repaid in substantially equal payments of principal and interest over a period of 20 years;

· we will pay Piper Sandler & Co. a fee equal to 1.35% of the aggregate dollar amount of the common stock sold in the subscription offering, assuming all shares are sold in the subscription offering (net of insider purchases, shares purchased by our ESOP and shares contributed to our charitable foundation);

· NB Bancorp will contribute $2.0 million in cash to our charitable foundation; and

· expenses of the offering, other than selling agent fees and expenses to be paid to Piper Sandler & Co., will be approximately $2.83 million.

We calculated pro forma consolidated net income for the six months ended June 30, 2023 and the year ended December 31, 2022 as if the estimated net proceeds we received had been invested at the beginning of the period at an assumed interest rate of 3.60% (2.70% on an after-tax basis). This represents the yield on the five-year U.S. Treasury Note as of June 30, 2023, which, in light of current market interest rates, we consider to more accurately reflect the pro forma reinvestment rate than the arithmetic average of the weighted average yield earned on our interest earning assets and the weighted average rate paid on our deposits, which is the reinvestment rate federal regulations provide that we assume in presenting pro forma data.

We further believe that the reinvestment rate is factually supportable because:

· the yield on the U.S, Treasury Note can be determined and/or estimated from third-party sources; and

· we believe that U.S. Treasury securities are not subject to credit losses due to a U.S. Government guarantee of payment of principal and interest.

We calculated historical and pro forma per share amounts by dividing historical and pro forma amounts of consolidated net income and stockholders’ equity by the indicated number of shares of common stock. We adjusted these figures to give effect to the shares of common stock purchased by the ESOP. We computed per share amounts for each period as if the shares of common stock were outstanding at the beginning of each period, but we did not adjust per share historical or pro forma stockholders’ equity to reflect the earnings on the estimated net proceeds.

52

The pro forma tables give effect to the implementation of stock-based benefit plans. Subject to the receipt of stockholder approval, we have assumed that the stock-based benefit plans will acquire for restricted stock awards a number of shares of common stock equal to 4% of our outstanding shares of common stock at the same price for which they were sold in the offering. We assume that shares of common stock are granted under the plans in awards that vest over a five-year period.

We have also assumed that options will be granted under the stock-based benefit plans to acquire shares of common stock equal to 10% of our outstanding shares of common stock. In preparing the tables below, we assumed that stockholder approval was obtained, that the exercise price of the stock options and the market price of the stock at the date of grant were $10.00 per share and that the stock options had a term of 10 years and vested over five years. We applied the Black-Scholes option pricing model to estimate a grant-date fair value of $5.07 for each option. In addition to the terms of the options described above, the Black-Scholes option pricing model assumed an estimated volatility rate of 32.30% for the shares of common stock, a dividend yield of 0%, an expected option life of 10 years and a risk-free interest rate of 3.81%.

We may grant options and award shares of common stock under one or more stock-based benefit plans in excess of 10% and 4%, respectively, of our total outstanding shares if the stock-based benefit plans are adopted more than one year following the offering. In addition, we may grant options and award shares that vest sooner than over a five-year period if the stock-based benefit plans are adopted more than one year following the offering.

As discussed under “How We Intend to Use the Proceeds from the Offering,” we intend to contribute at least 50% of the net proceeds to Needham Bank. We will retain the remainder of the net proceeds from the offering and use a portion of the proceeds we retain for the purpose of making a loan to the ESOP and retain the rest of the proceeds for future use.

The pro forma tables do not give effect to:

· withdrawals from deposit accounts for the purpose of purchasing shares of common stock in the offering;

· our results of operations after the offering, including the impact of additional expenses we expect to incur as a result of operating as a public company; or

· changes in the market price of the shares of common stock after the offering.

The following pro forma information may not represent the financial effects of the offering at the date on which the offering actually occurs and you should not use the table to indicate future results of operations. Pro forma stockholders’ equity represents the difference between the stated amount of our assets and liabilities, computed in accordance with GAAP. We did not increase or decrease stockholders’ equity to reflect the difference between the carrying value of loans and other assets and their market value. Pro forma stockholders’ equity is not intended to represent the fair market value of the shares of common stock and may be different than the amounts that would be available for distribution to stockholders if we liquidated. Pro forma stockholders’ equity does not give effect to the impact of intangible assets, the liquidation account we will establish in the conversion or tax bad debt reserves in the unlikely event we are liquidated.

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	At or For the Six Months Ended June 30, 2023 Based Upon the Sale at $10.00 Per Share of
	26,350,000 shares			31,000,000 shares			35,650,000 shares			40,997,500 shares (1)
	(Dollars in thousands, except per share amounts)
Gross proceeds of offering	$	263,500		$	310,000		$	356,500		$	409,975
Plus: Market value of shares issued to charitable foundation		10,979			12,917			14,854			17,082
Pro forma market capitalization	$	274,479		$	322,917		$	371,354		$	427,057
Gross proceeds of offering	$	263,500		$	310,000		$	356,500		$	409,975
Less: Expenses		(6,233	)		(6,808	)		(7,384	)		(8,046	)
Estimated net proceeds		257,267			303,192			349,116			401,929
Less:  Common stock purchased by ESOP (2)		(21,958	)		(25,833	)		(29,708	)		(34,165	)
Less:  Cash contribution to charitable foundation		(2,000	)		(2,000	)		(2,000	)		(2,000	)
Less:  Common stock awarded under stock-based benefit plans (3)		(10,979	)		(12,917	)		(14,854	)		(17,082	)
Estimated net cash proceeds	$	222,330		$	262,442		$	302,554		$	348,682
For the Six Months Ended June 30, 2023
Net income:
Historical	$	14,977		$	14,977		$	14,977		$	14,977
Pro forma income on net proceeds		3,444			4,065			4,686			5,400
Pro forma ESOP adjustment(2)		(412	)		(485	)		(557	)		(641	)
Pro forma stock award adjustment (3)		(824	)		(969	)		(1,114	)		(1,281	)
Pro forma stock option adjustment (4)		(1,305	)		(1,535	)		(1,765	)		(2,030	)
Pro forma net income (5)	$	15,880		$	16,053		$	16,227		$	16,425
Per share net income:
Historical	$	0.59		$	0.50		$	0.44		$	0.38
Pro forma income on net proceeds		0.14			0.14			0.14			0.14
Pro forma ESOP adjustment (2)		(0.02	)		(0.02	)		(0.02	)		(0.02	)
Pro forma stock award adjustment (3)		(0.03	)		(0.03	)		(0.03	)		(0.03	)
Pro forma stock option adjustment (4)		(0.05	)		(0.05	)		(0.05	)		(0.05	)
Pro forma net income per share (5) (6)	$	0.63		$	0.54		$	0.48		$	0.42
Offering price as a multiple of pro forma net income per share		7.94	x		9.26	x		10.42	x		11.90	x
Number of shares outstanding for pro forma net income per share calculations (5)		25,306,979			29,772,917			34,238,854			39,374,682
At June 30, 2023
Stockholders’ equity:
Historical	$	356,973		$	356,973		$	356,973		$	356,973
Estimated net proceeds		257,267			303,192			349,116			401,929
Market value of shares issued to charitable foundation		10,979			12,917			14,854			17,082
Expense of donation to foundation		(12,979	)		(14,917	)		(16,854	)		(19,082	)
Tax benefit of contribution to charitable foundation		3,245			3,729			4,214			4,771
Common stock acquired by ESOP (2)		(21,958	)		(25,833	)		(29,708	)		(34,165	)
Common stock awarded under stock-based benefit plans (3)		(10,979	)		(12,917	)		(14,854	)		(17,082	)
Pro forma stockholders’ equity (7)		582,548			623,144			663,741			710,426
Intangible assets		(1,303	)		(1,303	)		(1,303	)		(1,303	)
Pro forma tangible stockholders’ equity	$	581,245		$	621,841		$	662,438		$	709,123
Stockholders’ equity per share:
Historical	$	13.01		$	11.05		$	9.61		$	8.36
Estimated net proceeds		9.37			9.39			9.40			9.41
Market value of shares issued to charitable foundation		0.40			0.40			0.40			0.40
Expense of donation to foundation		(0.47	)		(0.46	)		(0.45	)		(0.45	)
Tax benefit of contribution to charitable foundation		0.12			0.12			0.11			0.11
Common stock acquired by ESOP (2)		(0.80	)		(0.80	)		(0.80	)		(0.80	)
Common stock awarded under stock-based benefit plans (3)		(0.40	)		(0.40	)		(0.40	)		(0.40	)
Pro forma stockholders’ equity per share (7)		21.23			19.30			17.87			16.63
Intangible assets		(0.05	)		(0.04	)		(0.04	)		(0.03	)
Pro forma tangible stockholders’ equity	$	21.18		$	19.26		$	17.83		$	16.60
Offering price as percentage of pro forma stockholders’ equity per share		47.10	%		51.81	%		55.96	%		60.13	%
Offering price as percentage of pro forma tangible stockholders’ equity per share		47.21	%		51.92	%		56.09	%		60.24	%
Number of shares outstanding for pro forma book value per share calculations (7)		27,447,917			32,291,667			37,135,417			42,705,729

footnotes begin on second following page)

54

	At or For the Year Ended December 31, 2022 Based Upon the Sale at $10.00 Per Share of
	26,350,000 shares			31,000,000 shares			35,650,000 shares			40,997,500 shares (1)
	(Dollars in thousands, except per share amounts)
Gross proceeds of offering	$	263,500		$	310,000		$	356,500		$	409,975
Plus: Market value of shares issued to charitable foundation		10,979			12,917			14,854			17,082
Pro forma market capitalization	$	274,479		$	322,917		$	371,354		$	427,057
Gross proceeds of offering	$	263,500		$	310,000		$	356,500		$	409,975
Expenses		(6,233	)		(6,808	)		(7,384	)		(8,046	)
Estimated net proceeds		257,267			303,192			349,116			401,929
Common stock purchased by ESOP (2)		(21,958	)		(25,833	)		(29,708	)		(34,165	)
Cash contribution to charitable foundation		(2,000	)		(2,000	)		(2,000	)		(2,000	)
Common stock awarded under stock-based benefit plans (3)		(10,979	)		(12,917	)		(14,854	)		(17,082	)
Estimated net cash proceeds	$	222,330		$	262,442		$	302,554		$	348,682
For the Year Ended December 31, 2022
Net income:
Historical	$	30,065		$	30,065		$	30,065		$	30,065
Pro forma income on net proceeds		6,887			8,129			9,372			10,800
Pro forma ESOP adjustment(2)		(823	)		(969	)		(1,114	)		(1,281	)
Pro forma stock award adjustment (3)		(1,647	)		(1,938	)		(2,228	)		(2,562	)
Pro forma stock option adjustment (4)		(2,609	)		(3,070	)		(3,530	)		(4,060	)
Pro forma net income (5)	$	31,873		$	32,217		$	32,565		$	32,962
Per share net income:
Historical	$	1.19		$	1.01		$	0.88		$	0.76
Pro forma income on net proceeds		0.27			0.27			0.27			0.27
Pro forma ESOP adjustment (2)		(0.03	)		(0.03	)		(0.03	)		(0.03	)
Pro forma stock award adjustment (3)		(0.06	)		(0.06	)		(0.06	)		(0.06	)
Pro forma stock option adjustment (4)		(0.10	)		(0.10	)		(0.10	)		(0.10	)
Pro forma net income per share (5) (6)	$	1.27		$	1.09		$	0.96		$	0.84
Offering price as a multiple of pro forma net income per share		7.87	x		9.17	x		10.42	x		11.90	x
Number of shares outstanding for pro forma net income per share calculations (5)		25,361,875			29,837,500			34,313,125			39,460,094
At December 31, 2022
Stockholders’ equity:
Historical	$	344,065		$	344,065		$	344,065		$	344,065
Estimated net proceeds		257,267			303,192			349,116			401,929
Market value of shares issued to charitable foundation		10,979			12,917			14,854			17,082
Expense of donation to foundation		(12,979	)		(14,917	)		(16,854	)		(19,082	)
Tax benefit of contribution to charitable foundation		3,245			3,729			4,214			4,771
Common stock acquired by ESOP (2)		(21,958	)		(25,833	)		(29,708	)		(34,165	)
Common stock awarded under stock-based benefit plans (3)		(10,979	)		(12,917	)		(14,854	)		(17,082	)
Pro forma stockholders’ equity (7)		569,640			610,236			650,833			697,518
Intangible assets		(1,377	)		(1,377	)		(1,377	)		(1,377	)
Pro forma tangible stockholders’ equity	$	568,263		$	608,859		$	649,456		$	696,141
Stockholders’ equity per share:
Historical	$	12.54		$	10.65		$	9.27		$	8.06
Estimated net proceeds		9.37			9.39			9.40			9.41
Market value of shares issued to charitable foundation		0.40			0.40			0.40			0.40
Expense of donation to foundation		(0.47	)		(0.46	)		(0.45	)		(0.45	)
Tax benefit of contribution to charitable foundation		0.12			0.12			0.11			0.11
Less:  Common stock acquired by ESOP (2)		(0.80	)		(0.80	)		(0.80	)		(0.80	)
Less:  Common stock awarded under stock-based benefit plans (3)		(0.40	)		(0.40	)		(0.40	)		(0.40	)
Pro forma stockholders’ equity per share (7)	$	20.76		$	18.90		$	17.53		$	16.33
Intangible assets		(0.05	)		(0.04	)		(0.04	)		(0.03	)
Pro forma tangible stockholders’ equity	$	20.71		$	18.86		$	17.49		$	16.30
Offering price as percentage of pro forma stockholders’ equity per share		48.17	%		52.91	%		57.05	%		61.24	%
Offering price as percentage of pro forma tangible stockholders’ equity per share		48.29	%		53.02	%		57.18	%		61.35	%
Number of shares outstanding for pro forma book value per share calculations (7)		27,447,917			32,291,667			37,135,417			42,705,729

(footnotes begin on following page)

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(1) As adjusted to give effect to an increase in the number of shares which could occur due to a 15% increase in the offering range to reflect demand for the shares or changes in market conditions following the commencement of the offering.

(2) Assumes that 8% of shares of common stock issued in the conversion (including shares to be contributed to the charitable foundation) will be purchased by the ESOP. For purposes of the tables, the funds used to acquire these shares are assumed to have been borrowed by the ESOP from NB Bancorp. Needham Bank intends to make annual contributions to the ESOP in an amount at least equal to the required principal and interest payments on the debt. Needham Bank’s total annual payments on the ESOP debt are based upon 20 equal annual installments of principal and interest. ASC 718-40 requires that an employer record compensation expense in an amount equal to the fair value of the shares committed to be released to employees. The pro forma adjustments assume that the ESOP shares are allocated in equal annual installments based on the number of loan repayment installments assumed to be paid by Needham Bank, the fair value of the common stock remains equal to the subscription price and the ESOP expense reflects an effective combined federal and state tax rate of 25%. The unallocated ESOP shares are reflected as a reduction of stockholders’ equity. No reinvestment is assumed on proceeds contributed to fund the ESOP. The pro forma net income further assumes that 54,896, 64,583, 74,271 and 85,411 shares were committed to be released during the six months ended June 30, 2023 at the minimum, midpoint, maximum and adjusted maximum of the offering range, respectively, and that 109,792, 129,167, 148,542 and 170,823 shares were committed to be released during the year ended December 31, 2022 at the minimum, midpoint, maximum and adjusted maximum of the offering range, respectively, and in accordance with ASC 718-40, only the ESOP shares committed to be released during the period were considered outstanding for purposes of income per share calculations.

(3) If approved by NB Bancorp’s stockholders, one or more stock-based benefit plans may grant an aggregate number of shares of common stock equal to 4% of the shares to be issued in the conversion, including shares contributed to the charitable foundation (or possibly a greater number of shares if the plan is implemented more than one year after completion of the conversion), as restricted stock awards to our officers, employees and directors. Stockholder approval of the stock-based benefit plans, and purchases by the plan, may not occur earlier than six months after the completion of the conversion. The shares may be acquired directly from NB Bancorp or through open market purchases. The funds to be used by the stock-based benefit plans to purchase the shares will be provided by NB Bancorp. The tables assume that (i) the stock-based benefit plans acquire the shares through open market purchases at $10.00 per share, (ii) 20% of the amount contributed to the stock-based benefit plans is amortized as an expense during the fiscal year and (iii) the stock-based benefit plans expense reflects an effective combined federal and state tax rate of 25%. Assuming stockholder approval of the stock-based benefit plans and that shares of common stock (equal to 4% of the shares issued in the conversion, including shares contributed to the charitable foundation) are awarded through the use of authorized but unissued shares of common stock, stockholders would have their ownership and voting interests diluted by approximately 3.85%.

(4) If approved by NB Bancorp’s stockholders, one or more stock-based benefit plans may grant options to acquire an aggregate number of shares of common stock equal to 10% of the shares to be issued in the conversion, including shares contributed to the charitable foundation (or possibly a greater number of shares if the plan is implemented more than one year after completion of the conversion). Stockholder approval of the stock-based benefit plans may not occur earlier than six months after the completion of the conversion. In calculating the pro forma effect of the stock options to be granted under stock-based benefit plans, it is assumed that the exercise price of the stock options and the trading price of the common stock at the date of grant were $10.00 per share, the estimated grant-date fair value determined using the Black-Scholes option pricing model was $5.07 for each option, the aggregate grant-date fair value of the stock options was amortized to expense on a straight-line basis over a five-year vesting period of the options, and that 25% of the amortization expense (or the assumed portion relating to options granted to directors) resulted in a tax benefit using an assumed tax rate of 25%. The actual expense of the stock options to be granted under the stock-based benefit plans will be determined by the grant-date fair value of the options, which will depend on a number of factors, including the valuation assumptions used in the option pricing model ultimately adopted. Under the above assumptions, the grant of options under the stock-based benefit plans will result in no additional shares under the treasury stock method for purposes of calculating earnings per share. There can be no assurance that the actual exercise price of the stock options will be equal to the $10.00 price per share. If a portion of the shares to satisfy the exercise of options under the stock-based benefit plans is obtained from the issuance of authorized but unissued shares, our net income per share and stockholders’ equity per share would decrease. Assuming stockholder approval of the stock-based benefit plans and that shares of common stock used to fund stock options (equal to 10% of the shares issued in the conversion, including shares contributed to