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

In the year to Sep 13, 2026, with distributions reinvested, IUSB returned −0.3% and MBB returned −0.1%, so MBB returned more. One year is one year; the longer windows are in the table.

Which is cheaper, IUSB or MBB?

IUSB charges 0.06% a year and MBB charges 0.04%, so MBB is cheaper. Fees come from each fund's prospectus.

Data as of Sep 13, 2026. Both funds on the fields they both publish, from the same sources.

ETFIQetfiq.com · independent ETF data

IUSB vs MBB: how they differ

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

iShares Core Universal USD Bond ETF and iShares MBS ETF.

What they hold in common

By the books each fund has filed, IUSB and MBB 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 IUSB	Only in MBB
United States of America 0.38%	BLACKROCK CASH CL INST SL AGENCY 7.26%
United States of America 0.37%	GNMA2 SF 30YR 0.09%
United States of America 0.37%	GNMA II 30YR SF - JUMBO-CONFORMING 0.08%
United States of America 0.37%	GNMA2 SINGLE FAMILY 30YR 0.04%
United States of America 0.36%	GNMA II 30YR 0.03%
United States of America 0.36%	GNMA2 30YR TBA(REG C) 0.03%
United States of America 0.36%	UMBS 15YR TBA(REG B) 0.03%
United States of America 0.35%	FNMA 30YR UMBS MEGA REMIC SUPER 0.02%

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 Apr 30, 2026 and Sep 10, 2026.

IUSB and MBB on the fields both publish, as of Sep 13, 2026. Source: ETFIQ.
	IUSB iShares Core Universal USD Bond ETF	MBB iShares MBS ETF
Where it sits	Core index fund	Core index fund
Issuer	iShares	iShares
What it is	Core Universal USD Bond	Mbs
Total return, 1 year	−0.3%	−0.1%
S&P 500 over the same days	+17.5%	+17.5%
Gap to the S&P 500	−17.8 pts	−17.6 pts
Expense ratio	0.06%	0.04%
Holdings	17819	2599

IUSB in plain words

IUSB is a bond fund tracking the Core Universal USD Bond. Over the year to Sep 11, 2026 it returned −0.3% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.06% a year.

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.

Questions people ask

Which returned more over the last year, IUSB or MBB?: In the year to Sep 13, 2026, with distributions reinvested, IUSB returned −0.3% and MBB returned −0.1%, so MBB returned more. One year is one year; the longer windows are in the table.
Which is cheaper, IUSB or MBB?: IUSB charges 0.06% a year and MBB charges 0.04%, so MBB is cheaper. Fees come from each fund's prospectus.

Other comparisons

Where to next

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.

IUSB against MBB, ETFIQ, data as of Sep 13, 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, IUSB against MBB, data as of Sep 13, 2026. https://etfiq.com/compare/any/iusb-vs-mbb Free to use with attribution; the underlying files are at Open data.

A comparison is not a recommendation. Standards and sources