MUB's largest holdings are Board of Regents of the University of Texas System, New York State Thruway Authority, San Antonio Water System, New York State Dormitory Authority, WILLIAM MARSH RICE UNIV. The full top list is on this page.

How concentrated is MUB?

The top 10 holdings are 1.4% of the fund, across 7,038 positions.

The total expense ratio on record is 0.05%. That is cheaper than 92% of the 864 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)

7,038 holdings as of 2026-08-27 · top 10 = 1.4% · TER 0.05%

Add to portfolioStart with this fund, then add the others you hold.

Concentration

Well diversifiedtop 10 = 1.4%

diversifiedconcentrated

GROWTH · PRICE DEVELOPMENTrebased to 0%

Holdings

7,038

as of 2026-08-27

Top 10

1.4%

TER

0.05%

cheaper than 92% of peers

Net assets

US$45.4B

reported in USD

Largest

0.2%

P / E

–

Sections

Holdings as of 2026-08-27.

01Overview

the fund's regulatory facts

Fund currency

USD

Domicile

United States

Volatility 1Y

3.2%

Tracked index

ICE AMT-Free US National Municipal Index

How it tracks

Index, sampling

02Performance

market price return · as of 2026-09-11

-2.7%

-3.6%

-3.8%

YTD

-3.7%

-3.1%

Trackingfund minus ICE AMT-Free US National Municipal Index · annualised

1Y return gap

+0.02 pp/yr

3Y return gap

-0.12 pp/yr

5Y return gap

-0.03 pp/yr

3Y tracking error

0.12%

A positive return gap means the fund finished ahead of the index over that window. The 3Y tracking error shows how variable that monthly gap was; lower means steadier tracking. MethodologyReturn gap and tracking errorReturn gap is the fund's return minus its index over the same months, converted to a yearly rate. Tracking error is the annualised standard deviation of those monthly fund-minus-index returns. Both lines come from the manager's own chart, in the same currency and the exact index variant the fund tracks. We use month-end values so different intraday valuation times are not mistaken for tracking error.. Not investment advice.

03Holdings

50 largest · as of 2026-08-27

#	Company	Identifier	Weight
1	Board of Regents of the University of Texas System US	US91514ANG66	0.2
2	New York State Thruway Authority US	US650028ZA41	0.2
3	San Antonio Water System US	US79642GTU66	0.1
4	New York State Dormitory Authority US	NYSHGR	0.1
5	WILLIAM MARSH RICE UNIV US	HOUHGR	0.1
6	Northwest Independent School District US	US667826HG94	0.1
7	New Jersey (State of) US	US646039YM35	0.1
8	Ohio State University/The US	OHSHGR	0.1
9	State of California US	US13063D7Q50	0.1
10	Washington (State of) (Bid Group 2) US	US93974EVY93	0.1
11	Chicago Transit Authority Sales Tax Receipts Fund US	US16772PEP71	0.1
12	East County Advanced Water Purification Joint Powers Authority US	EAWWTR	0.1
13	City of Seattle US	US812643ZK32	0.1
14	Triborough Bridge & Tunnel Authority US	US89602RPH20	0.1
15	City of Houston TX Combined Utility System Revenue US	US44244CN944	0.1
16	ILLINOIS ST US	ILS	0.1
17	Washoe County School District US	US940859BX82	0.1
18	New Jersey Educational Facilities Authority US	US646067KD94	0.1
19	County of King WA Sewer Revenue US	US495290ET12	0.1
20	Commonwealth of Massachusetts US	US57582R8A79	0.1
21	State of California US	US13063D4Q87	0.1
22	Commonwealth of Massachusetts US	US57582R2F21	0.1
23	DIST OF COLUMBIA UNIV REVENUE US	US25484JDJ60	0.1
24	New York City Municipal Water Finance Authority US	US64972GH724	0.1
25	City of New York US	US64966SPY62	0.1
26	City of Chicago IL US	US167486T338	0.1
27	City of Colorado Springs Utilities System US	US1966326N82	0.1
28	METROPOLITAN ATLANTA RAPID TRA US	US591746EE80	0.1
29	San Diego Unified School District US	US797356BY75	0.1
30	Triborough Bridge & Tunnel Authority US	US89602HGZ47	0.1
31	New York City Municipal Water Finance Authority US	US64972GPZ18	0.1
32	NEW JERSEY ST TRANSPRTN TRUST US	US646136EV97	0.1
33	New York (State of) Thruway Authority US	US650028ZU05	0.1
34	Triborough Bridge & Tunnel Authority US	US89602HAB33	0.1
35	Ohio Water Development Authority US	US67766WQ212	0.1
36	California Educational Facilities Authority US	US130179YE89	0.1
37	Los Angeles Unified School District US	US544647BX71	0.1
38	University of California US	US91412HPR83	0.1
39	Pennsylvania Turnpike Commission US	US7092248P76	0.1
40	Empire State Development Corp US	US650036AP19	0.1
41	New Jersey Educational Facilities Authority US	US646067HR28	0.1
42	New York State Thruway Authority US	US650028YW79	0.1
43	New York State Thruway Authority US	US650028D427	0.1
44	Commonwealth of Massachusetts US	US57582R2Z84	0.1
45	Metropolitan Government of Nashville & Davidson County US	US592112XP62	0.1
46	Massachusetts Bay Transportation Authority Sales Tax US	US575579W298	0.1
47	Commonwealth of Massachusetts Transportation Fund US	US57604TKJ42	0.1
48	City of New York NY US	US64966SCS32	0.1
49	Bay Area Toll Authority US	US072024YU07	0.1
50	University of California US	US91412HPS66	0.1

Add this fund to your portfolio →

04Exposure

Bonds 98.5%Cash 1.5%

By country

USUnited States97.2%

CurrencyUSD 97.2%

See this fund inside your whole portfolio

Paste every fund you hold and see the companies you actually own, merged across all of them, with overlap, concentration and portfolio P/E. You can also test what adding this ETF would change.

Add to portfolio →