Which returned more over the last year, MBB or MUB?

In the year to Sep 12, 2026, with distributions reinvested, MBB returned −0.1% and MUB returned +0.1%, so MUB returned more. One year is one year; the longer windows are in the table.

Which is cheaper, MBB or MUB?

MBB charges 0.04% a year and MUB charges 0.05%, so MBB is cheaper. Fees come from each fund's prospectus.

Data as of Sep 12, 2026. Both funds on the fields they both publish, from the same sources.

ETFIQetfiq.com · independent ETF data

MBB vs MUB: how they differ

MBB and MUB hold 0% of their weight in the same names.

iShares MBS ETF and iShares National Muni Bond ETF.

What they hold in common

By the books each fund has filed, MBB and MUB hold 0% of their money in the same securities at the same weight.

Largest positions each one holds and the other does not
Only in MBB	Only in MUB
Freddie Mac 1.07%	Board of Regents of the University of Te 0.20%
Government National Mortgage Association 0.97%	New York State Thruway Authority 0.16%
UMBS, TBA 0.85%	New York State Dormitory Authority 0.14%
Government National Mortgage Association 0.69%	Houston Higher Education Finance Corp. 0.13%
UMBS, TBA 0.66%	Northwest Independent School District 0.13%
Government National Mortgage Association 0.56%	Ohio State University (The) 0.13%
Government National Mortgage Association 0.55%	State of New Jersey 0.13%
Government National Mortgage Association 0.54%	State of California 0.13%

Weight overlap is an ETFIQ calculation: for every security both funds hold, the smaller of the two weights, summed. Above 50%, holding both is close to holding one of them twice. Holdings dated May 31, 2026.

MBB and MUB on the fields both publish, as of Sep 12, 2026. Source: ETFIQ.
	MBB iShares MBS ETF	MUB iShares National Muni Bond ETF
Where it sits	Core index fund	Core index fund
Issuer	iShares	iShares
What it is	Mbs	National Muni Bond
Total return, 1 year	−0.1%	+0.1%
S&P 500 over the same days	+17.5%	+17.5%
Gap to the S&P 500	−17.6 pts	−17.4 pts
Expense ratio	0.04%	0.05%
Holdings	11144	6603

MBB in plain words

MBB is a bond fund tracking the Mbs. Over the year to Sep 11, 2026 it returned −0.1% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.04% a year. It sat 3.3% below its high of Feb 27, 2026 on Sep 11, 2026.

MUB in plain words

MUB is a bond fund tracking the National Muni Bond. Over the year to Sep 11, 2026 it returned +0.1% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.05% a year. It sat 3.6% below its high of Jul 6, 2026 on Sep 11, 2026.

Questions people ask

Which returned more over the last year, MBB or MUB?: In the year to Sep 12, 2026, with distributions reinvested, MBB returned −0.1% and MUB returned +0.1%, so MUB returned more. One year is one year; the longer windows are in the table.
Which is cheaper, MBB or MUB?: MBB charges 0.04% a year and MUB charges 0.05%, so MBB is cheaper. Fees come from each fund's prospectus.

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Where these figures came from

ETFIQ links to the documents behind every figure. It is not affiliated with any issuer, and a link is not an endorsement.

MBB against MUB, ETFIQ, data as of Sep 12, 2026. Every figure is arithmetic on a named public source; the method is at etfiq.com/methodology. A comparison is not a recommendation.

Cite this page. ETFIQ, MBB against MUB, data as of Sep 12, 2026. https://etfiq.com/compare/any/MBB-MUB Free to use with attribution; the underlying files are at Open data.

A comparison is not a recommendation. Standards and sources