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

In the year to Sep 13, 2026, with distributions reinvested, IWB returned +16.7% and MBB returned −0.1%, so IWB returned more. One year is one year; the longer windows are in the table.

Which is cheaper, IWB or MBB?

IWB charges 0.15% 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

IWB vs MBB: how they differ

IWB and MBB hold 0% of their weight in the same names, and IWB returned more over the year.

iShares Russell 1000 ETF and iShares MBS ETF.

What they hold in common

By the books each fund has filed, IWB 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 IWB	Only in MBB
NVIDIA 7.26%	BLACKROCK CASH CL INST SL AGENCY 7.26%
APPLE 6.73%	GNMA2 SF 30YR 0.09%
MICROSOFT 5.21%	GNMA II 30YR SF - JUMBO-CONFORMING 0.08%
AMAZON.COM INC 3.49%	GNMA2 SINGLE FAMILY 30YR 0.04%
ALPHABET CLASS A 2.77%	GNMA II 30YR 0.03%
BROADCOM INC 2.40%	GNMA2 30YR TBA(REG C) 0.03%
ALPHABET CLASS C 2.24%	UMBS 15YR TBA(REG B) 0.03%
META PLATFORMS CLASS A 2.02%	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 Sep 10, 2026.

IWB and MBB on the fields both publish, as of Sep 13, 2026. Source: ETFIQ.
	IWB iShares Russell 1000 ETF	MBB iShares MBS ETF
Where it sits	Core index fund	Core index fund
Issuer	iShares	iShares
What it is	Russell 1000	Mbs
Total return, 1 year	+16.7%	−0.1%
S&P 500 over the same days	+17.5%	+17.5%
Gap to the S&P 500	−0.8 pts	−17.6 pts
Expense ratio	0.15%	0.04%
Holdings	945	2599

IWB in plain words

IWB is an index equity fund tracking the Russell 1000. Over the year to Sep 11, 2026 it returned +16.7% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.15% a year. By its holdings filed for Sep 10, 2026, 92% of the fund by weight is stocks the S&P 500 also holds, across 945 positions, with the top ten at 35.2%.

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, IWB or MBB?: In the year to Sep 13, 2026, with distributions reinvested, IWB returned +16.7% and MBB returned −0.1%, so IWB returned more. One year is one year; the longer windows are in the table.
Which is cheaper, IWB or MBB?: IWB charges 0.15% a year and MBB charges 0.04%, 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.

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

A comparison is not a recommendation. Standards and sources