Filed Pursuant to Rule 424(b)(3)

Registration No. 333-194280

	PROSPECTUS  SUPPLEMENT NO. 1 DECEMBER 19, 2014
GRIFFIN CAPITAL ESSENTIAL ASSET REIT II

SUPPLEMENT NO. 1 DATED DECEMBER 19, 2014

TO THE PROSPECTUS DATED DECEMBER 8, 2014

This document supplements, and should be read in conjunction with, the prospectus of Griffin Capital Essential Asset REIT II, Inc. dated December 8, 2014. Unless otherwise defined in this supplement, capitalized terms used in this supplement shall have the same meanings as set forth in the prospectus.

The purpose of this supplement is to disclose:

• an update on the status of our offering;

• the addition of a "Debt Summary" section of our prospectus; and

• inclusion of a multi-product subscription agreement.

Status of Our Offering

We commenced the initial public offering of shares of our common stock on July 31, 2014. On September 23, 2014, we reached the minimum offering amount of $2.0 million in sales of shares as a result of a $2.0 million investment by a private investment program affiliated with our sponsor, and commenced operations at such point. On November 12, 2014, we announced that we were no longer offering shares of our Class T common stock in our offering, and thus we will reallocate the shares being offered such that we will be offering up to $2.0 billion in shares of Class A common stock in our primary offering and up to $200 million in shares of Class A common stock pursuant to our distribution reinvestment plan. As of November 12, 2014, we had not sold any shares of Class T common stock in the offering.

As of December 15, 2014, we have received gross offering proceeds of approximately $6.9 million from the sale of 719,957 Class A shares in our initial public offering, including proceeds raised and shares issued under our distribution reinvestment plan. As of December 15, 2014, approximately $2.193 billion in shares of common stock remained available for sale to the public under our initial public offering, including shares available under our distribution reinvestment plan.

Addition of "Debt Summary" Section

The following is added as a new subsection of the "Real Estate Investments" section of our prospectus:

Debt Summary

On December 12, 2014, we, through our operating partnership (the "Borrower"), entered into that certain revolving credit agreement related to a loan with a syndicate of lenders, under which KeyBank, National Association ("KeyBank") serves as administrative agent and JPMorgan Chase Bank, N.A. ("JPMorgan") serves as syndication agent, and various notes related thereto. In addition, we entered into a guaranty agreement.

Pursuant to the credit agreement, we were provided with a revolving credit facility (the "KeyBank Revolving Credit Facility") in an initial commitment amount of $250 million, which commitment may be increased under certain circumstances up to a maximum total commitment of $1.25 billion. The KeyBank Revolving Credit Facility is evidenced by promissory notes that are substantially similar related to each lender and the amount committed by such lender. Increases in the commitment amount must be made in amounts of not less than $100 million, and increases of $50 million in increments in excess thereof. The Borrower may also reduce the commitment amount in increments of $50 million, provided that at no time will the KeyBank Revolving Credit Facility be less than $100 million, and such a reduction will preclude the Borrower's ability to later increase the commitment amount.

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Amounts owed under the KeyBank Revolving Credit Facility will be evidenced by promissory notes that will be substantially similar other than identification of each lender and the amount committed by such lender. Amounts borrowed under the KeyBank Revolving Credit Facility may be repaid and re-borrowed, subject to the terms of the credit agreement, and are determined from time to time by book entry.

The KeyBank Revolving Credit Facility also provides for same day swingline advances to be provided by KeyBank (with participation by the other lenders equal to their pro rata share of the KeyBank Revolving Credit Facility), up to $25 million in the aggregate. Such swingline advances will reduce dollar for dollar the availability under the KeyBank Revolving Credit Facility, and must be repaid within 10 business days.

The KeyBank Revolving Credit Facility has an initial term of four years, maturing on December 12, 2018. The KeyBank Revolving Credit Facility may be extended for a one-year period if certain conditions are met and the Borrower pays an extension fee. Payments under the KeyBank Revolving Credit Facility are interest only and are due on the first day of each quarter.

The KeyBank Revolving Credit Facility has an interest rate calculated based on LIBOR plus the applicable LIBOR margin, as provided in the credit agreement, or the Base Rate plus the applicable base rate margin, as provided in the credit agreement. The applicable LIBOR margin and base rate margin are dependent on the consolidated leverage ratio of the Borrower, us, and our subsidiaries, as disclosed in the periodic compliance certificate provided to the Administrative Agent each quarter, and are dependent upon whether the security for the KeyBank Revolving Credit Facility has been released, as provided below. If the Borrower obtains an investment grade rating of its senior unsecured long term debt from Standard & Poor's Rating Services or Moody's Investors Service, Inc., the applicable LIBOR margin and base rate margin will be dependent on such rating.

The credit agreement relating to the KeyBank Revolving Credit Facility provides that the Borrower must maintain a pool of real properties (each a "Pool Property" and collectively the "Pool Properties") that meet certain requirements contained in the credit agreement. The credit agreement sets forth certain covenants relating to the Pool Properties, including, without limitation, the following:

• from September 12, 2015 through July 12, 2016, there must be no less than four Pool Properties; from July 12, 2016 through December 12, 2016, there must be no less than eight Pool Properties; and after December 12, 2016, there must be no less than 15 Pool Properties;

• for the one-year period following December 12, 2015, no greater than 35% of the aggregate pool value may be contributed by a single Pool Property; and for the one-year period following December 12, 2016, no greater than 15% of the aggregate pool value may be contributed by a single Pool Property;

• for the one-year period following December 12, 2015, no greater than 35% of the aggregate pool value may be contributed by a single tenant; and for the one-year period following December 12, 2016, no greater than 15% of the aggregate pool value may be contributed by a single tenant;

• no greater than 15% of the aggregate pool value may be contributed by Pool Properties subject to ground leases;

• no greater than 20% of the aggregate pool value may be contributed by Pool Properties which are under development;

• the minimum aggregate occupancy of all Pool Properties must be no less than 90%; and

• other limitations as determined by KeyBank upon further due diligence of the Pool Properties.

Borrowing availability under the KeyBank Revolving Credit Facility is limited to the lesser of (i) an asset pool leverage ratio of no greater than 60%, or (ii) an asset pool debt service coverage ratio of 1.35:1.00.

The KeyBank Revolving Credit Facility will initially be secured by a pledge of 100% of the ownership interests in each special purpose entity which owns a Pool Property. Upon the occurrence of each of the following as it relates to the Borrower, us, and our subsidiaries, the security for the KeyBank Revolving Credit Facility shall be released, at Borrower's request, provided there is no event of default then existing, and the facility will then be deemed an unsecured revolver:

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• total asset value of no less than $500 million;

• tangible net worth of no less than $250 million;

• fixed charge coverage ratio of no less than 1.50:1.00;

• consolidated leverage ratio of no greater than 60%;

• no less than 15 Pool Properties in the asset pool; and

• no single Pool Property represents greater than 15% of the asset pool value.

In connection with the KeyBank Revolving Credit Facility, the Borrower paid arrangement fees equal to a total of $875,000. The Borrower also paid a commitment fee equal to $987,500 based on the allocated commitments from each participating lender, and will pay KeyBank an administrative agent fee of $25,000 per year. In addition, an unused fee will be payable quarterly which is calculated based on the amount of the unused revolving loan commitments and is equal to 15 basis points if 50% or more of the loan commitments are used or 25 basis points if less than 50% of the loan commitments are used. At the time that the applicable LIBOR margin and base rate margin are determined in accordance with the Borrower's investment grade rating as provided above, the Borrower will pay a quarterly facility fee at a rate that is dependent on such rating and is based upon the total commitments.

The KeyBank Revolving Credit Facility may be prepaid and terminated, in whole or in part, at any time without fees or penalty. Guarantors of the KeyBank Revolving Credit Facility include us, each special purpose entity that owns a Pool Property, and each of our other subsidiaries which owns a direct or indirect equity interest in a special purpose entity that owns a Pool Property.

In addition to customary representations, warranties, covenants, and indemnities, the KeyBank Revolving Credit Facility requires us to comply with the following at all times, which will be tested on a quarterly basis:

• a maximum consolidated leverage ratio of 60%, or, once the collateral pledges are released, the ratio may increase to 65% for up to four consecutive quarters after a material acquisition only after the facility is deemed unsecured;

• a minimum consolidated tangible net worth of 80% of our consolidated tangible net worth at closing of the KeyBank Revolving Credit Facility, or approximately $4.7 million, plus 75% of net future equity issuances (including units of operating partnership interests in the Borrower);

• a minimum consolidated fixed charge coverage ratio of not less than 1.50:1.00, commencing as of the quarter ending March 31, 2016;

• a maximum total secured debt ratio of not greater than 40%, which ratio will increase by five percentage points for four quarters after closing of a material acquisition that is financed with secured debt;

• a maximum total secured recourse debt ratio, excluding recourse obligations associated with interest rate hedges, of 10% of our total asset value, at the time our tangible net worth equals or exceeds $250 million (secured debt is not permitted prior to the time our tangible net worth exceeds $250 million);

• aggregate maximum unhedged variable rate debt of not greater than 30% of our total asset value; and

• a maximum payout ratio of not greater than 95% of our core funds from operations, commencing as of the quarter ending March 31, 2018.

Furthermore, the activities of the Borrower, us, and our subsidiaries must be focused principally on the acquisition, operation, and maintenance of income producing office and industrial real estate properties. The credit agreement contains certain restrictions with respect to the investment activities of the Borrower, including, without limitation, the following: (i) undeveloped land may not exceed 5% of total asset value; (ii) developments that are pre-leased assets under development may not exceed 20% of total asset value; (iii) investments in unconsolidated affiliates may not exceed 10% of total asset value; and (iv) investments in mortgage notes receivable may not exceed 5% of total asset value. These investment limitations cannot exceed 25% in the aggregate, based on total asset value, as defined in the credit agreement.

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Subscription Agreement

Attached hereto as Appendix A is a multi-product subscription agreement for investors who wish to invest in our offering and in the offering of Griffin-American Healthcare REIT III, Inc., another non-traded REIT co-sponsored by our sponsor. This multi-product subscription agreement is for use only through participating dealers that have signed a participating dealer agreement with our dealer manager for each respective company's offering, and is subject to certain other restrictions outlined further in the document itself.

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Appendix A - 1

Appendix A - 2

Appendix A - 3

Appendix A - 4

Appendix A - 5