MUB's largest holdings are BlackRock Liquidity Funds MuniCash, Board of Regents of the University of Texas System, Connecticut State Health & Educational Facilities Authority, City of Atlanta GA Water & Wastewater Revenue, Northwest Independent School District. The full top list is on this page.

How concentrated is MUB?

The top 10 holdings are 2.1% of the fund, across 6264 positions.

The total expense ratio on record is 0.05%. That is cheaper than 91% of the 786 US-listed bond funds we track.

US-listed · United States

MUB

The Fund seeks to track the investment results of an index composed of investment-grade U.S. municipal bonds.

iShares National Muni Bond ETF

US4642884146 · BlackRock (iShares)

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Concentration

Well diversifiedtop 10 = 2.1%

diversifiedconcentrated

GROWTH · NAV (USD)rebased to 0%

Holdings

6264

as of 2026-02-28

Top 10

2.1%

TER

0.05%

cheaper than 91% of peers

Net assets

≈ US$43.0B

as filed

Largest

0.6%

P / E

–

Sections

Holdings as of 2026-02-28.

01Overview

the fund's regulatory facts

Fund currency

USD

Domicile

United States

Volatility 1Y

3.0%

How it tracks

Index, sampling

02Performance

price · as of 2026-07-23

-1.6%

-1.1%

-0.5%

YTD

-0.1%

+5.0%

03Holdings

50 largest · as of 2026-02-28

#	Company	Identifier	Weight
1	BlackRock Liquidity Funds MuniCash US	MCSXX	0.6
2	Board of Regents of the University of Texas System US	US91514ANG66	0.2
3	Connecticut State Health & Educational Facilities Authority US	US20775DL756	0.2
4	City of Atlanta GA Water & Wastewater Revenue US	ATLUTL	0.2
5	Northwest Independent School District US	US667826HG94	0.2
6	New York State Thruway Authority US	US650028ZA41	0.2
7	WILLIAM MARSH RICE UNIV US	HOUHGR	0.2
8	New York State Dormitory Authority US	NYSHGR	0.1
9	Ohio State University/The US	US677632T926	0.1
10	State of California US	US13063D7Q50	0.1
11	New Jersey (State of) US	US646039YM35	0.1
12	Washington (State of) (Bid Group 2) US	US93974EVY93	0.1
13	Pennsylvania Turnpike Commission US	US709224M309	0.1
14	Chicago Transit Authority Sales Tax Receipts Fund US	US16772PEP71	0.1
15	New Jersey Educational Facilities Authority US	US646067HR28	0.1
16	Washoe County School District US	US940859BX82	0.1
17	New Jersey Educational Facilities Authority US	US646067KD94	0.1
18	East County Advanced Water Purification Joint Powers Authority US	EAWWTR	0.1
19	State of California US	US13063D4Q87	0.1
20	ILLINOIS ST US	US452152P965	0.1
21	Commonwealth of Massachusetts US	US57582R8A79	0.1
22	DIST OF COLUMBIA UNIV REVENUE US	US25484JDJ60	0.1
23	New York City Municipal Water Finance Authority US	US64972GH724	0.1
24	Commonwealth of Massachusetts US	US57582R2F21	0.1
25	City of New York US	US64966SPY62	0.1
26	California Educational Facilities Authority US	US130179YE89	0.1
27	San Diego Unified School District US	US797356BY75	0.1
28	City of Colorado Springs Utilities System US	US1966326N82	0.1
29	Triborough Bridge & Tunnel Authority US	US89602HGZ47	0.1
30	NEW JERSEY ST TRANSPRTN TRUST US	US646136EV97	0.1
31	Los Angeles Unified School District US	US544647BX71	0.1
32	University of California US	US91412HPR83	0.1
33	Empire State Development Corp US	US650036AP19	0.1
34	New York City Municipal Water Finance Authority US	US64972GPZ18	0.1
35	Commonwealth of Pennsylvania US	PAS	0.1
36	Triborough Bridge & Tunnel Authority US	US89602HAB33	0.1
37	New York (State of) Thruway Authority US	US650028ZU05	0.1
38	New York State Thruway Authority US	US650028YW79	0.1
39	Ohio Water Development Authority US	US67766WQ212	0.1
40	State of Maryland US	US574193WD67	0.1
41	Metropolitan Government of Nashville & Davidson County US	US592112XP62	0.1
42	New York State Thruway Authority US	US650028D427	0.1
43	Pennsylvania Turnpike Commission US	US7092248P76	0.1
44	Maryland (State of) Stadium Authority (Baltimore City Public Schools) US	US574296AX73	0.1
45	City of New Orleans US	US64763FJ592	0.1
46	Commonwealth of Massachusetts US	US57582R2Z84	0.1
47	Massachusetts Bay Transportation Authority Sales Tax US	US575579W298	0.1
48	University of California US	US91412HPS66	0.1
49	Prosper Independent School District US	US7436005D64	0.1
50	County of Ector US	US279245KU72	0.1

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04Exposure

Equity 0.6%Bonds 98.4%Cash 1.1%

By country

USUnited States99.5%

CurrencyUSD 99.5%

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