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

In the year to Oct 9, 2026, with distributions reinvested, MBB returned −1.2% and PMBS −2.0%.

Which is cheaper, MBB or PMBS?

MBB is cheaper, by 0.67 percentage points a year. That is about $67 on $10,000 held for a year. Fees come from each fund's prospectus.

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MBB vs PMBS: Differences, Returns & Fees

MBB's duration was 5.4 years on May 31, 2026 and PMBS's 6.3 on Jun 30, 2026; MBB charges 0.04% to PMBS's 0.71%. Net assets: $35.6bn on Oct 9, 2026 for iShares MBS ETF, and $1.4bn on Jun 30, 2026 for PIMCO Mortgage-Backed Securities Active Exchange-Traded Fund.

MBB costs 0.67 points a year less; their one-year returns differ by 0.8 points; MBB is far larger, $39.6bn against $1.4bn.

	MBB	PMBS
Expense ratio	0.04%	0.71%
Net assets, as of Jun 30, 2026	$39.6bn	$1.4bn
Total return, 1 year	−1.2%	−2.0%
What it tracks	Bloomberg U.S. MBS Index	No index, actively managed
Holdings in common	0%
Below its high	4.6%, high on Feb 27, 2026	5.9%, high on Feb 27, 2026

Holdings in common uses holdings dated May 31, 2026 and Jun 30, 2026.

−1.2%

MBB total return, 1 year

−2.0%

PMBS total return, 1 year

0.04%

MBB expense ratio

0.71%

PMBS expense ratio

What they hold in common

By the books each fund has filed, MBB and PMBS hold 0% 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 and Jun 30, 2026.

50%

half

0% in common

Positions both hold, largest shared weight first

Holding MBB PMBS

Freddie Mac Pool, due Oct 1, 2054 0.11% 0.70%

Ginnie Mae II Pool, due Mar 20, 2052 0.07% 1.23%

Fannie Mae Pool, due Mar 1, 2054 0.06% 0.26%

Ginnie Mae II Pool, due Aug 20, 2055 0.02% 0.19%

Ginnie Mae II Pool, due Nov 20, 2045 0.03% 0.01%

Ginnie Mae II Pool, due Dec 20, 2045 0.01% 0.01%

Ginnie Mae II Pool, due Feb 20, 2048 0.01% 0.01%

Freddie Mac Pool, due Sep 1, 2053 0.04% 0.01%

Ginnie Mae II Pool, due Nov 20, 2048 0.00% 0.01%

Ginnie Mae II Pool, due Jan 20, 2049 0.04% 0.00%

Ginnie Mae II Pool, due Feb 20, 2049 0.00% 0.01%

Fannie Mae Pool, due May 1, 2035 0.00% 0.01%

Only in MBB

Freddie Mac Pool, due May 1, 2051 1.05%

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%

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

Ginnie Mae II Pool, due Oct 20, 2051 0.54%

Ginnie Mae II Pool, due Dec 20, 2051 0.53%

Only in PMBS

Uniform Mortgage-Backed Security, TBA, due Sep 1, 2056 7.72%

Uniform Mortgage-Backed Security, TBA, due Aug 1, 2056 6.94%

Uniform Mortgage-Backed Security, TBA, due Jul 1, 2056 5.26%

Uniform Mortgage-Backed Security, TBA, due Aug 1, 2056 3.96%

Government National Mortgage Association, due Nov 20, 2055 3.67%

Federal Home Loan Mortgage Corp., due Mar 1, 2056 3.51%

Uniform Mortgage-Backed Security, TBA, due Aug 1, 2056 3.22%

Uniform Mortgage-Backed Security, TBA, due Aug 1, 2056 3.17%

Check overlap with more funds →

On the same fields

MBB

iShares MBS ETF

PMBS

PIMCO Mortgage-Backed Securities Active Exchange-Traded Fund

Where it sits Bond ETF Bond ETF

Issuer iShares PIMCO

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

Total return, 1 year −1.2% −2.0%

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

Gap to the S&P 500 −18.5 pts −19.3 pts

Expense ratio 0.04% 0.71%

Holdings 10855 1134

Net assets, MBB as of Oct 9, 2026 and PMBS as of Jun 30, 2026 $35.6bn $1.4bn

MBB and PMBS 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.

PMBS in plain words

PMBS is actively managed and tracks no index. Over the year to Oct 9, 2026 it returned −2.0% with distributions reinvested. The prospectus expense ratio is 0.71% a year. It sat 5.9% below its high of Feb 27, 2026 on Oct 9, 2026.

Questions people ask

Which returned more over the last year, MBB or PMBS?: In the year to Oct 9, 2026, with distributions reinvested, MBB returned −1.2% and PMBS −2.0%.
Which is cheaper, MBB or PMBS?: MBB is cheaper, by 0.67 percentage points a year. That is about $67 on $10,000 held for a year. Fees come from each fund's prospectus.

Other comparisons

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

MBB on its own →PMBS 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 ↗PMBS filings on SEC EDGAR ↗PMBS prospectus with the expense ratio (SEC) ↗PIMCO 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 PMBS, data as of Oct 9, 2026. https://etfiq.com/compare/any/mbb-vs-pmbs

Open data

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