Schedule of Investments (unaudited) August 31, 2022 BlackRock Impact Municipal Fund (Percentages shown are based on Net Assets)

Security	Par (000)		Value
Municipal Bonds
Alabama — 0.2%
Sumter County Industrial Development Authority, RB, AMT, 6.00%, 07/15/52(a)	$	100	$	98,166
Arizona — 1.9%
Arizona Industrial Development Authority, RB, Series A, 4.00%, 02/01/50		1,000		922,846
Arkansas — 2.3%
University of Arkansas, RB, Series A, 5.00%, 04/01/47		1,000		1,097,003
California — 17.4%
California Community Choice Financing Authority, RB, Series A, 4.00%, 10/01/52(a)		1,500		1,575,679
California Public Finance Authority, RB
Series A, 4.00%, 07/15/51		1,000		963,867
Series B-3, 2.13%, 11/15/27(b)		250		232,040
California School Finance Authority, RB, 5.00%, 08/01/42(b)		125		129,364
California State Public Works Board, RB, Series D, Class D, 4.00%, 05/01/45		1,000		999,456
City of Los Angeles California Wastewater System Revenue, Refunding RB, Series A, Subordinate, 4.00%, 06/01/52		1,500		1,434,022
CSCDA Community Improvement Authority, RB, M/F Housing(b)
3.25%, 04/01/57		250		185,101
Series A-2, 3.00%, 02/01/57		350		250,966
Los Angeles County Metropolitan Transportation Authority Sales Tax Revenue, RB, Series A, 4.00%, 06/01/37		1,000		1,035,636
Los Angeles Unified School District, GO, 4.00%, 07/01/37		500		512,213
Val Verde Unified School District, GO, Series B, (AGM), 4.00%, 08/01/51		1,000		968,418
				8,286,762
Colorado — 1.2%
Denver City & County School District No. 1, GO, Series A, (SAW), 5.00%, 12/01/42		500		562,439
Connecticut — 5.4%
Connecticut State Health & Educational Facilities Authority, RB, Series A, Class A, 4.00%, 07/01/51		500		455,909
State of Connecticut, GO, 2020, 4.00%, 01/15/37		1,000		1,009,937
University of Connecticut, RB, Series A, 5.00%, 05/01/39		1,000		1,121,487
				2,587,333
Delaware — 0.2%
Affordable Housing Opportunities Trust, Series AH-01, Class B, 6.88%, 05/01/39(b)(c)		80		75,943
District of Columbia — 2.3%
District of Columbia, RB, Class A-AMT, AMT, 5.50%, 02/28/34		1,000		1,102,857
Florida — 6.6%
Brevard County Health Facilities Authority, Refunding RB, Series A, 4.00%, 04/01/52		1,000		889,551
Broward County Florida Water & Sewer Utility Revenue, RB, Series A, 4.00%, 10/01/47		500		485,741
County of Miami-Dade Florida Water & Sewer System Revenue, RB, 4.00%, 10/01/48		1,000		943,665

Security	Par (000)		Value
Florida (continued)
Florida Development Finance Corp., RB
Series A, Class A, 4.00%, 06/15/42	$	500	$	445,205
Series A, Class A, 5.00%, 06/15/47		375		381,719
				3,145,881
Georgia — 0.7%
Georgia Housing & Finance Authority, Refunding RB, S/F Housing, Series A, Class A, 4.00%, 06/01/49		325		337,687
Illinois — 2.7%
Chicago Transit Authority Sales Tax Receipts Fund, Refunding RB, Series A, Class A, 2nd Lien, 5.00%, 12/01/52		1,200		1,283,138
Indiana — 0.8%
City of Bloomington Indian Sewage Works Revenue, RB, (BAM), 4.00%, 01/01/39		400		387,044
Kentucky — 2.9%
City of Henderson Kentucky, RB, Series SE, Class A, AMT, 4.70%, 01/01/52(b)		350		339,171
Louisville/Jefferson County Metropolitan Government, RB, Series A, (AGM), 5.00%, 05/15/47		1,000		1,058,525
				1,397,696
Louisiana — 2.6%
Jefferson Parish Consolidated Sewerage District No. 1, RB, (BAM), 4.00%, 02/01/42		1,000		972,308
Louisiana Public Facilities Authority, RB, Series A, 6.38%, 06/01/52(b)		250		256,868
				1,229,176
Maine — 0.2%
Finance Authority of Maine, RB, AMT, 8.00%, 12/01/51(b)		100		83,395
Maryland — 1.6%
Maryland Economic Development Corp., RB, Class B, AMT, 5.25%, 06/30/47		715		754,858
Massachusetts — 5.6%
Massachusetts Bay Transportation Authority Assessment Revenue, Refunding RB, Series A, 5.00%, 07/01/52		1,500		1,659,311
University of Massachusetts Building Authority, RB, Series 1, 4.00%, 11/01/46		1,000		1,000,576
				2,659,887
Michigan — 2.0%
Ludington Area School District, GO, Series II, (BAM), 4.00%, 05/01/51		1,000		943,252
Minnesota — 1.1%
Duluth Economic Development Authority, RB, Class B, 5.25%, 06/15/42		500		523,498
New Hampshire — 1.5%
New Hampshire Housing Finance Authority, RB, M/F Housing,Series 2022, 4.38%, 09/20/36		748		718,084
New York — 12.1%
Battery Park City Authority, RB, 4.00%, 11/01/44		1,500		1,519,756
Build NYC Resource Corp., RB, Series A, 5.00%, 07/01/32		245		236,857
Metropolitan Transportation Authority, Refunding RB, Series A-1, 5.00%, 11/15/49		1,000		1,025,121
New York City Municipal Water Finance Authority, RB, Series CC-1, 4.00%, 06/15/52		1,000		946,047

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Schedule of Investments (unaudited) (continued) August 31, 2022 BlackRock Impact Municipal Fund (Percentages shown are based on Net Assets)

Security	Par (000)		Value
New York (continued)
New York Power Authority, RB
(AGM), 4.00%, 11/15/39	$	1,000	$	1,004,581
(AGM), 4.00%, 11/15/40		1,000		1,004,699
				5,737,061
North Carolina — 0.5%
North Carolina Housing Finance Agency, RB, S/F Housing, (FHLMC, FNMA, GNMA), 3.75%, 07/01/52		250		250,972
North Dakota — 0.5%
North Carolina Housing Finance Agency, RB, S/F Housing, Series A, 4.00%, 01/01/53		230		235,078
Ohio — 3.5%
Ohio State University, RB, Series B-1, VRDN, 1.53%, 12/01/39(a)(d)		1,500		1,500,000
Southern Ohio Port Authority, RB, Series A, AMT, 7.00%, 12/01/42(b)		200		174,856
				1,674,856
Oklahoma — 2.1%
Oklahoma Water Resources Board, RB, Series A, 4.00%, 10/01/51		995		980,913
Oregon — 1.4%
Oregon State Facilities Authority, RB, Series A, 5.00%, 06/01/52		125		131,494
State of Oregon Housing & Community Services Department, RB, S/F Housing, Series A, 4.00%, 07/01/51		545		548,497
				679,991
Pennsylvania — 3.4%
City of Philadelphia Pennsylvania Water & Wastewater Revenue, RB, Series C, 5.50%, 06/01/47		1,000		1,130,634
Pennsylvania Housing Finance Agency, Refunding RB, S/F Housing, Series 2022, 4.25%, 10/01/52		475		487,485
				1,618,119
South Carolina — 1.5%
South Carolina State Housing Finance & Development Authority, RB, S/F Housing, Series A, 4.00%, 01/01/52		680		690,677
Tennessee — 0.4%
Tennessee Housing Development Agency, Refunding RB, S/F Housing, Series 1, 3.75%, 07/01/52		200		201,330
Texas — 4.2%
Arlington Higher Education Finance Corp., RB (PSF), 5.00%, 08/15/47		500		549,249

Security	Par (000)		Value
Texas (continued)
Arlington Higher Education Finance Corp., RB (continued)
Series A, 5.25%, 08/15/32	$	250	$	252,315
City of El Paso Texas Water & Sewer Revenue, Refunding RB, 5.00%, 03/01/46		1,000		1,086,129
New Hope Cultural Education Facilities Finance Corp., Refunding RB, Class A, 6.63%, 10/01/43		100		100,510
				1,988,203
Utah — 3.7%
University of Utah, RB, Series A, 4.00%, 08/01/43		1,500		1,474,261
Utah Infrastructure Agency, RB, 5.00%, 10/15/32		250		265,415
				1,739,676
Virginia — 2.2%
Henrico County Economic Development Authority, Refunding RB, Class A, 5.00%, 10/01/47		1,000		1,056,554
Total Long-Term Investments — 94.7% (Cost: $47,511,747)				45,050,375
	Shares
Short-Term Securities
Money Market Funds — 3.9%
BlackRock Liquidity Funds, MuniCash, Institutional Class, 1.19%(e)(f)		1,878,710		1,878,898
Total Short-Term Securities — 3.9% (Cost: $1,878,922)				1,878,898
Total Investments — 98.6% (Cost: $49,390,669)				46,929,273
Other Assets Less Liabilities — 1.4%				664,167
Net Assets — 100.0%			$	47,593,440

^(a)  Variable rate security. Interest rate resets periodically. The rate shown is the effective interest rate as of period end. Security description also includes the reference rate and spread if published and available.

^(b)  Security exempt from registration pursuant to Rule 144A under the Securities Act of 1933, as amended. These securities may be resold in transactions exempt from registration to qualified institutional investors.

^(c)  Security is valued using significant unobservable inputs and is classified as Level 3 in the fair value hierarchy.

^(d)  Variable rate security. Rate as of period end and maturity is the date the principal owed can be recovered through demand.

^(e)  Affiliate of the Fund.

^(f)  Annualized 7-day yield as of period end.

For Fund compliance purposes, the Fund’s sector classifications refer to one or more of the sector sub-classifications used by one or more widely recognized market indexes or rating group indexes, and/or as defined by the investment adviser. These definitions may not apply for purposes of this report, which may combine such sector sub-classifications for reporting ease.

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Schedule of Investments (unaudited) (continued) August 31, 2022 BlackRock Impact Municipal Fund

Affiliates

Investments in issuers considered to be affiliate(s) of the Fund during the period ended August 31, 2022 for purposes of Section 2(a)(3) of the Investment Company Act of 1940, as amended, were as follows:

Affiliated Issuer	Value at 05/31/22		Purchases at Cost		Proceeds from Sales			Net Realized Gain (Loss)		Change in Unrealized Appreciation (Depreciation)			Value at 08/31/22		Shares Held at 08/31/22		Income		Capital Gain Distributions from Underlying Funds
BlackRock Liquidity Funds, MuniCash, Institutional Class	$	1,983,841	$	—	$	(104,837	)(a)	$	120	$	(226	)	$	1,878,898		1,878,710	$	2,171	$	—

^(a)  Represents net amount purchased (sold).

Derivative Financial Instruments Outstanding as of Period End

Futures Contracts

Description	Number of Contracts		Expiration Date		Notional Amount (000)		Value/ Unrealized Appreciation (Depreciation)
Short Contracts
10-Year U.S. Treasury Note		28		12/20/22	$	3,273	$	33,381
U.S. Long Bond		32		12/20/22		4,347		4,201
5-Year U.S. Treasury Note		12		12/30/22		1,330		4,551
							$	42,133

Fair Value Hierarchy as of Period End

Various inputs are used in determining the fair value of financial instruments. These inputs to valuation techniques are categorized into a fair value hierarchy consisting of three broad levels for financial reporting purposes as follows:

• Level 1 – Unadjusted price quotations in active markets/exchanges for identical assets or liabilities that the Fund has the ability to access;

• Level 2 – Other observable inputs (including, but not limited to, quoted prices for similar assets or liabilities in markets that are active, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the assets or liabilities (such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks and default rates) or other market–corroborated inputs); and

• Level 3 – Unobservable inputs based on the best information available in the circumstances, to the extent observable inputs are not available (including the Valuation Committee’s assumptions used in determining the fair value of financial instruments).

The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). Accordingly, the degree of judgment exercised in determining fair value is greatest for instruments categorized in Level 3. The inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes, the fair value hierarchy classification is determined based on the lowest level input that is significant to the fair value measurement in its entirety. Investments classified within Level 3 have significant unobservable inputs used by the Valuation Committee in determining the price for Fair Valued Investments. Level 3 investments include equity or debt issued by privately held companies or funds. There may not be a secondary market, and/or there are a limited number of investors. The categorization of a value determined for financial instruments is based on the pricing transparency of the financial instruments and is not necessarily an indication of the risks associated with investing in those securities. For information about the Fund’s policy regarding valuation of financial instruments, refer to its most recent financial statements.

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Schedule of Investments (unaudited) (continued) August 31, 2022 BlackRock Impact Municipal Fund

Fair Value Hierarchy as of Period End (continued)

The following table summarizes the Fund’s financial instruments categorized in the fair value hierarchy. The breakdown of the Fund’s financial instruments into major categories is disclosed in the Schedule of Investments above.

	Level 1		Level 2		Level 3		Total
Assets
Investments
Long-Term Investments
Municipal Bonds	$	—	$	44,974,432	$	75,943	$	45,050,375
Short-Term Securities
Money Market Funds		1,878,898		—		—		1,878,898
	$	1,878,898	$	44,974,432	$	75,943	$	46,929,273
Derivative Financial Instruments(a)
Assets
Interest Rate Contracts	$	42,133	$	—	$	—	$	42,133

^(a)  Derivative financial instruments are futures contracts. Futures contracts are valued at the unrealized appreciation (depreciation) on the instrument.

Portfolio Abbreviation

AGM	Assured Guaranty Municipal Corp.
AMT	Alternative Minimum Tax
BAM	Build America Mutual Assurance Co.
FHLMC	Federal Home Loan Mortgage Corp.
FNMA	Federal National Mortgage Association
GNMA	Government National Mortgage Association
GO	General Obligation Bonds
M/F	Multi-Family
PSF	Permanent School Fund
RB	Revenue Bond
S/F	Single-Family
SAW	State Aid Withholding
VRDN	Variable Rate Demand Note

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