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

ETFIQetfiq.com · independent ETF data

MBB vs VOO: how they differ

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

iShares MBS ETF and Vanguard 500 Index Fund.

What they hold in common

By the books each fund has filed, MBB and VOO 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 MBBOnly in VOO
BLACKROCK CASH CL INST SL AGENCY 7.26%NVIDIA Corp 7.53%
GNMA2 SF 30YR 0.09%Apple Inc 6.61%
GNMA II 30YR SF - JUMBO-CONFORMING 0.08%Microsoft Corp 4.31%
GNMA2 SINGLE FAMILY 30YR 0.04%Amazon.com Inc 3.63%
GNMA II 30YR 0.03%Alphabet Inc 3.26%
GNMA2 30YR TBA(REG C) 0.03%Broadcom Inc 2.78%
UMBS 15YR TBA(REG B) 0.03%Alphabet Inc 2.60%
FNMA 30YR UMBS MEGA REMIC SUPER 0.02%Micron Technology Inc 2.02%

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 Jun 30, 2026 and Sep 10, 2026.

MBB and VOO on the fields both publish, as of Sep 13, 2026. Source: ETFIQ.
MBB
iShares MBS ETF
VOO
Vanguard 500 Index Fund
Where it sitsCore index fundCore index fund
IssueriSharesVanguard
What it isMbsS&P 500
Total return, 1 year−0.1%+17.6%
S&P 500 over the same days+17.5%+17.5%
Gap to the S&P 500−17.6 pts+0.1 pts
Expense ratio0.04%0.03%
Holdings2599506

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.

VOO in plain words

VOO is an index equity fund tracking the S&P 500. Over the year to Sep 11, 2026 it returned +17.6% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.03% a year. By its holdings filed for Jun 30, 2026, 100% of the fund by weight is stocks the S&P 500 also holds, across 506 positions, with the top ten at 36.5%.

Questions people ask

Which returned more over the last year, MBB or VOO?
In the year to Sep 13, 2026, with distributions reinvested, MBB returned −0.1% and VOO returned +17.6%, so VOO returned more. One year is one year; the longer windows are in the table.
Which is cheaper, MBB or VOO?
MBB charges 0.04% a year and VOO charges 0.03%, so VOO 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 VOO, 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, MBB against VOO, data as of Sep 13, 2026. https://etfiq.com/compare/any/mbb-vs-voo Free to use with attribution; the underlying files are at Open data.

A comparison is not a recommendation. Standards and sources