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

In the year to Oct 9, 2026, with distributions reinvested, MBB returned −1.2% and SMBS −1.0%.

Which is cheaper, MBB or SMBS?

SMBS is cheaper, by 0.01 percentage points a year. That is about $1 on $10,000 held for a year. Fees come from each fund's prospectus.

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MBB vs SMBS: Differences, Returns & Fees

On May 31, 2026 MBB's duration was 5.4 years and SMBS's 5.1; SMBS charges 0.03% to MBB's 0.04%. Net assets: $35.6bn on Oct 9, 2026 for iShares MBS ETF, and $6.4bn on May 31, 2026 for Schwab Mortgage-Backed Securities ETF.

SMBS costs 0.01 points a year less; their one-year returns differ by 0.2 points; MBB is far larger, $37.6bn against $54m.

	MBB	SMBS
Expense ratio	0.04%	0.03%
Net assets, as of Feb 28, 2025	$37.6bn	$54m
Total return, 1 year	−1.2%	−1.0%
What it tracks	Bloomberg U.S. MBS Index	Bloomberg US MBS Float Adjusted Total Return Index
Holdings in common	18%
Below its high	4.6%, high on Feb 27, 2026	4.4%, high on Feb 27, 2026

Holdings in common uses holdings dated May 31, 2026.

−1.2%

MBB total return, 1 year

−1.0%

SMBS total return, 1 year

0.04%

MBB expense ratio

0.03%

SMBS expense ratio

What they hold in common

By the books each fund has filed, MBB and SMBS hold 18% of their money in the same securities at the same weight. Above 50%, holding both is close to holding one of them twice. Holdings dated May 31, 2026.

50%

half

18% in common

Positions both hold, largest shared weight first

Holding MBB SMBS

Ginnie Mae II Pool, due Nov 20, 2054 0.55% 0.47%

Freddie Mac Pool, due Mar 1, 2051 0.22% 0.21%

Ginnie Mae II Pool, due Dec 20, 2054 0.20% 0.19%

Freddie Mac Pool, due Mar 1, 2052 0.18% 0.25%

Ginnie Mae II Pool, due Feb 20, 2051 0.16% 0.19%

Fannie Mae Pool, due Apr 1, 2052 0.17% 0.16%

Fannie Mae Pool, due Jul 1, 2051 0.15% 0.16%

Ginnie Mae II Pool, due Nov 20, 2054 0.15% 0.16%

Ginnie Mae II Pool, due Jul 20, 2051 0.45% 0.15%

Freddie Mac Pool, due Dec 1, 2051 0.24% 0.14%

Ginnie Mae II Pool, due Dec 20, 2051 0.27% 0.14%

Ginnie Mae II Pool, due Dec 20, 2050 0.28% 0.14%

Only in MBB

Ginnie Mae, due Jun 20, 2056 0.95%

Uniform Mortgage-Backed Security, TBA, due Jun 1, 2056 0.83%

Ginnie Mae, due Jun 20, 2056 0.67%

Uniform Mortgage-Backed Security, TBA, due Jun 1, 2056 0.64%

Fannie Mae Pool, due Dec 1, 2051 0.52%

Ginnie Mae, due Jun 20, 2056 0.46%

Fannie Mae Pool, due Jul 1, 2051 0.44%

Uniform Mortgage-Backed Security, TBA, due Jun 1, 2056 0.34%

Only in SMBS

Freddie Mac Pool, due Jan 1, 2054 0.29%

Freddie Mac Pool, due Apr 1, 2056 0.25%

Freddie Mac Pool, due Aug 1, 2055 0.24%

Ginnie Mae II Pool, due Dec 20, 2055 0.24%

Freddie Mac Pool, due Jan 1, 2052 0.23%

Freddie Mac Pool, due Dec 1, 2050 0.22%

Freddie Mac Pool, due Mar 1, 2056 0.21%

Ginnie Mae II Pool, due Nov 20, 2055 0.21%

Check overlap with more funds →

On the same fields

MBB

iShares MBS ETF

SMBS

Schwab Mortgage-Backed Securities ETF

Where it sits Bond ETF Bond ETF

Issuer iShares Schwab

What it is Tracks an index of mortgage-backed securities Tracks an index

Total return, 1 year −1.2% −1.0%

S&P 500 over the same days +17.3% +17.3%

Gap to the S&P 500 −18.5 pts −18.2 pts

Expense ratio 0.04% 0.03%

Holdings 10855 4196

Net assets, MBB as of Oct 9, 2026 and SMBS as of May 31, 2026 $35.6bn $6.4bn

MBB and SMBS on the fields both publish, as of Oct 9, 2026. Source: ETFIQ.

MBB in plain words

MBB tracks an index of mortgage-backed securities. The prospectus expense ratio is 0.04% a year. It sat 4.6% below its high of Feb 27, 2026 on Oct 9, 2026.

Over the year to Oct 9, 2026 it returned −1.2% with distributions reinvested, against −1.4% for its benchmark, the Bloomberg U.S. MBS Index.

SMBS in plain words

SMBS tracks an index. Over the year to Oct 9, 2026 it returned −1.0% with distributions reinvested, against −1.2% for its benchmark, the Bloomberg US MBS Float Adjusted Total Return Index, measured by the closely related Bloomberg U.S. MBS Index. The prospectus expense ratio is 0.03% a year. It sat 4.4% below its high of Feb 27, 2026 on Oct 9, 2026.

Questions people ask

Which returned more over the last year, MBB or SMBS?: In the year to Oct 9, 2026, with distributions reinvested, MBB returned −1.2% and SMBS −1.0%.
Which is cheaper, MBB or SMBS?: SMBS is cheaper, by 0.01 percentage points a year. That is about $1 on $10,000 held for a year. Fees come from each fund's prospectus.

Other comparisons

MBB vs PMBS JMBS vs MBB MBB vs SPMB FSEC vs MBB SMBS vs VMBS FSEC vs SMBS SMBS vs SPMB JMBS vs SMBS

MBB on its own →SMBS on its own →Hold both: look the portfolio through →Rankings →Standards and sources →

Where these figures came from

MBB filings on SEC EDGAR ↗MBB prospectus with the expense ratio (SEC) ↗iShares page for MBB ↗SMBS filings on SEC EDGAR ↗SMBS prospectus with the expense ratio (SEC) ↗Schwab website ↗

ETFIQ links to the documents behind every figure; a link is not an endorsement. A comparison is not a recommendation.

How this is computed

Overlap adds up the smaller of the two weights for each security both funds hold.

Cite this pageCitation, APA and Markdown

ETFIQ, MBB against SMBS, data as of Oct 9, 2026. https://etfiq.com/compare/any/mbb-vs-smbs

Open data

Free to use with attribution for figures ETFIQ computes; issuer data stays under its owner's terms.