BLACKROCK ETF TRUST II

BlackRock High Yield Muni Income Bond ETF

BlackRock Intermediate Municipal Income Bond ETF

(each, a “Fund” and together, the “Funds”)

Supplement dated March 27, 2023 (the “Supplement”) to the Funds’

Statement of Additional Information dated November 28, 2022

The following changes are made to the Funds’ Statement of Additional Information:

The section of the Statement of Additional Information entitled “Investment Advisory, Administrative and Distribution Services — Portfolio Managers” is deleted in its entirety and replaced with the following:

Portfolio Managers. As of July 31, 2022, the individuals named as Portfolio Managers in the Funds’ Prospectuses were also primarily responsible for the day-to-day management of other BlackRock funds and certain other types of portfolios and/or accounts as follows:

Kevin Maloney, CFA
Types of Accounts	Number	Total Assets
Registered Investment Companies	7	$4.83 Billion
Other Pooled Investment Vehicles	0	0
Other Accounts	0	0

James Mauro
Types of Accounts	Number	Total Assets
Registered Investment Companies	122	$548.83 Billion
Other Pooled Investment Vehicles	24	47.73 Billion
Other Accounts	6	8.57 Billion

Ryan McDonald, CFA1
Types of Accounts	Number	Total Assets
Registered Investment Companies	5	$11.20 Billion
Other Pooled Investment Vehicles	0	0
Other Accounts	0	0

¹  Information provided as of February 28, 2023.

Christian Romaglino, CFA
Types of Accounts	Number	Total Assets
Registered Investment Companies	11	$6.26 Billion
Other Pooled Investment Vehicles	0	0
Other Accounts	0	0

Phillip Soccio, CFA
Types of Accounts	Number	Total Assets
Registered Investment Companies	10	$5.63 Billion
Other Pooled Investment Vehicles	0	0
Other Accounts	0	0

Pursuant to BFA’s policy, investment opportunities are allocated equitably among the Funds and other portfolios and accounts. For example, under certain circumstances, an investment opportunity may be restricted due to limited supply in the market, legal constraints or other factors, in which event the investment opportunity will be allocated equitably among those portfolios and accounts, including the Funds, seeking such investment opportunity. As a consequence, from time to time the Fund may receive a smaller allocation of an investment opportunity than it would have if the Portfolio Managers and BFA and its affiliates did not manage other portfolios or accounts.

Like the Funds, the other portfolios or accounts for which the Portfolio Managers are primarily responsible for the day-to-day portfolio management generally pay an asset-based fee to BFA or its affiliates, as applicable, for its advisory services. One or more of those other portfolios or accounts, however, may pay BFA or its affiliates a performance-based fee in lieu of, or in addition to, an asset-based fee for its advisory services. A portfolio or account with a performance-based fee would pay BFA or its affiliates a portion of that portfolio’s or account’s gains, or would pay BFA or its affiliates more for its services than would otherwise be the case if BFA or any of its affiliates meets or exceeds specified performance targets. Performance-based fee arrangements could present an incentive for BFA or its affiliates to devote greater resources, and allocate more investment opportunities, to the portfolios or accounts that have those fee arrangements, relative to other portfolios or accounts, in order to earn larger fees. Although BFA and each of its affiliates have an obligation to allocate resources and opportunities equitably among portfolios and accounts and intend to do so, shareholders of the Funds should be aware that, as with any group of portfolios and accounts managed by an investment adviser and/or its affiliates pursuant to varying fee arrangements, including performance-based fee arrangements, there is the potential for a conflict of interest, which may result in the Portfolio Managers favoring those portfolios or accounts with performance-based fee arrangements.

The tables below show, for each Portfolio Manager, the number of portfolios or accounts of the types set forth in the above tables and the aggregate of total assets in those portfolios or accounts with respect to which the investment management fees are based on the performance of those portfolios or accounts as of July 31, 2022:

Kevin Maloney, CFA
Types of Accounts	Number of Other Accounts with Performance Fees Managed by Portfolio Manager		Aggregate of Total Assets
Registered Investment Companies		0		$	0
Other Pooled Investment Vehicles		0			0
Other Accounts		0			0

James Mauro
Types of Accounts	Number of Other Accounts with Performance Fees Managed by Portfolio Manager		Aggregate of Total Assets
Registered Investment Companies		0		$	0
Other Pooled Investment Vehicles		0			0
Other Accounts		0			0

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Ryan McDonald, CFA1
Types of Accounts	Number of Other Accounts with Performance Fees Managed by Portfolio Manager		Aggregate of Total Assets
Registered Investment Companies		0		0
Other Pooled Investment Vehicles		0		0
Other Accounts		0		0

¹  Information provided as of February 28, 2023.

Christian Romaglino, CFA
Types of Accounts	Number of Other Accounts with Performance Fees Managed by Portfolio Manager		Aggregate of Total Assets
Registered Investment Companies		0		$	0
Other Pooled Investment Vehicles		0			0
Other Accounts		0			0

Phillip Soccio, CFA
Types of Accounts	Number of Other Accounts with Performance Fees Managed by Portfolio Manager		Aggregate of Total Assets
Registered Investment Companies		0		$	0
Other Pooled Investment Vehicles		0			0
Other Accounts		0			0

The discussion below describes the compensation each Portfolio Manager other than Mr. McDonald as of July 31, 2022 and the compensation of Mr. McDonald as of February 28, 2023.

Portfolio Manager Compensation Overview

BlackRock, Inc.’s financial arrangements with its portfolio managers, its competitive compensation and its career path emphasis at all levels reflect the value senior management places on key resources. Compensation may include a variety of components and may vary from year to year based on a number of factors. The principal components of compensation include a base salary, a performance-based discretionary bonus, participation in various benefits programs and one or more of the incentive compensation programs established by BlackRock, Inc.

Base compensation. Generally, portfolio managers receive base compensation based on their position with the firm.

Discretionary Incentive Compensation. Discretionary incentive compensation is a function of several components: the performance of BlackRock, Inc., the performance of the portfolio manager’s group within BlackRock, the investment performance, including risk-adjusted returns, of the firm’s assets under management or supervision by that portfolio manager, and the individual’s performance and contribution to the overall performance of these portfolios and BlackRock. Among other things, BlackRock’s Chief Investment Officers make a subjective determination with respect to each portfolio manager’s compensation based on the performance of the Funds and other accounts managed by each portfolio manager. Performance of multi-asset

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class funds is generally measured on a pre-tax basis over various time periods including 1-, 3- and 5- year periods, as applicable. With respect to these portfolio managers, such benchmarks for the Fund and other accounts are:

Portfolio Manager	Benchmarks
Kevin Maloney Michael Perilli Christian Romaglino Phil Soccio Ryan McDonald	A combination of market-based indices (e.g., Bloomberg Municipal Bond Index), certain customized indices and certain fund industry peer groups.
James Mauro	A combination of market-based indices (e.g., Bloomberg MBS Index and the Bloomberg U.S. TIPS 0-5 Years Index).

Distribution of Discretionary Incentive Compensation. Discretionary incentive compensation is distributed to portfolio managers in a combination of cash, deferred BlackRock, Inc. stock awards, and/or deferred cash awards that notionally track the return of certain BlackRock investment products.

Portfolio managers receive their annual discretionary incentive compensation in the form of cash. Portfolio managers whose total compensation is above a specified threshold also receive deferred BlackRock, Inc. stock awards annually as part of their discretionary incentive compensation. Paying a portion of discretionary incentive compensation in the form of deferred BlackRock, Inc. stock puts compensation earned by a portfolio manager for a given year “at risk” based on BlackRock’s ability to sustain and improve its performance over future periods. In some cases, additional deferred BlackRock, Inc. stock may be granted to certain key employees as part of a long-term incentive award to aid in retention, align interests with long-term shareholders and motivate performance. Deferred BlackRock, Inc. stock awards are generally granted in the form of BlackRock, Inc. restricted stock units that vest pursuant to the terms of the applicable plan and, once vested, settle in BlackRock, Inc. common stock. The portfolio managers of these Funds have deferred BlackRock, Inc. stock awards.

For certain portfolio managers, a portion of the discretionary incentive compensation is also distributed in the form of deferred cash awards that notionally track the returns of select BlackRock investment products they manage, which provides direct alignment of portfolio manager discretionary incentive compensation with investment product results. Deferred cash awards vest ratably over a number of years and, once vested, settle in the form of cash. Only portfolio managers who manage specified products and whose total compensation is above a specified threshold are eligible to participate in the deferred cash award program.

Other Compensation Benefits. In addition to base compensation and discretionary incentive compensation, portfolio managers may be eligible to receive or participate in one or more of the following:

Incentive Savings Plans — BlackRock, Inc. has created a variety of incentive savings plans in which BlackRock, Inc. employees are eligible to participate, including a 401(k) plan, the BlackRock Retirement Savings Plan (“RSP”), and the BlackRock Employee Stock Purchase Plan (“ESPP”). The employer contribution components of the RSP include a company match equal to 50% of the first 8% of eligible pay contributed to the plan capped at $5,000 per year, and a company retirement contribution equal to 3-5% of eligible compensation up to the U.S. Internal Revenue Service (the “IRS”) limit ($305,000 for 2022). The RSP offers a range of investment options, including registered investment companies and collective investment funds managed by the firm. BlackRock, Inc. contributions follow the investment direction set by participants for their own contributions or, absent participant investment direction, are invested into an index target date fund that corresponds to, or is closest to, the year in which the participant attains age 65. The ESPP allows for investment in BlackRock, Inc. common stock at a 5% discount on the fair market value of the stock on the purchase date. Annual participation in the ESPP is limited to the purchase of 1,000 shares of common stock or a dollar value of $25,000 based on its fair market value on the Purchase Date. All of the eligible portfolio managers are eligible to participate in these plans.

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As of July 31, 2022, the Portfolio Managers other than Mr. McDonald did not beneficially own shares of their respective Funds, and as of February 28, 2023, Mr. McDonald did not beneficially own shares of BlackRock High Yield Muni Income Bond ETF.

Shareholders should retain this Supplement for future reference.

SAI-HYMIBE-0323SUP

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