Are IBB and MBB in the same category?

IBB is a thematic ETF and MBB is a bond ETF, so they do different jobs. The table compares what both publish: return, cost and holdings.

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

In the year to Oct 28, 2026, with distributions reinvested, IBB returned +37.5% and MBB −0.8%.

Which is cheaper, IBB or MBB?

MBB is cheaper, by 0.40 percentage points a year. That is about $40 on $10,000 held for a year. Fees come from each fund's prospectus.

Data as of Oct 28, 2026.

Across categories

IBB vs MBB: Differences, Returns & Fees

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Over the year to Oct 28, 2026, IBB returned +37.5% to MBB's −0.8%, and MBB charges 0.04% to IBB's 0.44%.

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Net assets: $11.0bn on Oct 27, 2026 for iShares Biotechnology ETF, and $35.5bn on Oct 28, 2026 for iShares MBS ETF.

IBB on its own →MBB on its own →

At a glance

+37.5%

IBB total return, 1 year

−0.8%

MBB total return, 1 year

0.44%

IBB expense ratio

0.04%

MBB expense ratio

Pair scorecard

MBB costs 0.40 points a year less; their one-year returns differ by 38.3 points; MBB is 3.3 times larger.

IBB vs MBB: Differences, Returns & Fees
Measure	IBB	MBB
Return
Measure	IBB	MBB
Total return, 1 year	+37.5%	−0.8%
Benchmark
Measure	IBB	MBB
What it tracks	Biotech	Bloomberg U.S. MBS Index
Cost and size
Measure	IBB	MBB
Expense ratio	0.44%	0.04%
Net assets, as of Oct 26, 2026	$10.7bn	$35.6bn
Active share vs the S&P 500	99%
Holdings
Measure	IBB	MBB
Holdings in common	0%
In the S&P 500, by weight	40%
Top ten holdings, share of the fund	50%

Holdings in common uses holdings dated Oct 27, 2026. Method

Risk and return

Mar 23, 2007 to Oct 23, 2026 · 1,022 weekly returns

IBB MBB

Return

Total return edge IBB +760.0% +63.4%

Annualized edge IBB +11.6% +2.5%

Price return edge IBB +723.3% −9.6%

Risk

Volatility edge MBB 22.9% 4.2%

Max drawdown edge MBB −37.5% −17.4%

Risk-adjusted

Sharpe edge IBB 0.53 0.24

Sortino edge IBB 0.76 0.35

Calmar edge IBB 0.31 0.15

Reading

IBB returned more: +760.0% to +63.4%. MBB swung less: 4.2% to 22.9%. MBB fell less at its worst: −17.4% to −37.5%.

Full scorecard

9 measures, with how each is measured Open ↓

Risk and return: IBB vs MBB: Differences, Returns & Fees
Measure	IBB	MBB	Edge	How it is measured
Return
Total return	+760.0%	+63.4%	IBB	Price change plus distributions, reinvested.
Annualized	+11.6%	+2.5%	IBB	Total return as a yearly rate.
Price return	+723.3%	−9.6%	IBB	Price change alone, distributions left out.
Risk
Volatility	22.9%	4.2%	MBB	Spread of weekly returns, annualized. Lower is steadier.
Downside deviation	15.9%	2.9%	MBB	Like volatility, counting only weeks below the Treasury bill rate.
Max drawdown	−37.5%	−17.4%	MBB	Deepest fall from a high to the low after it.
Risk-adjusted
Sharpe	0.53	0.24	IBB	Return above Treasury bills per unit of volatility.
Sortino	0.76	0.35	IBB	Return above Treasury bills per unit of downside deviation.
Calmar	0.31	0.15	IBB	Annualized return divided by the max drawdown.

Computed by ETFIQ from Tiingo daily prices and ETFIQ's distribution records, 1,022 weekly returns. Cash rate: the 13-week Treasury bill.

What they share

By the books each fund has filed, IBB and MBB hold 0% of their money in the same securities at the same weight. Holdings dated Oct 27, 2026.

50%

0 half 100%

half

0% in common

Positions both hold · largest shared weight first IBB MBB

Only in one fund ↓

Only in IBB

GILEAD SCIENCES 8.56%

AMGEN INC 8.20%

VERTEX PHARMACEUTICALS 7.53%

REGENERON PHARMACEUTICALS 5.64%

MODERNA 5.29%

NATERA 3.85%

ARGENX SE ADR 3.42%

ILLUMINA INC 2.93%

Only in MBB

BLACKROCK CASH CL INST SL AGENCY 5.45%

FHLMC 30YR UMBS SUPER 1.05%

UMBS 30YR TBA(REG A) 0.60%

GNMA2 30YR 0.59%

GNMA2 30YR 0.54%

FNMA 30YR UMBS 0.53%

GNMA2 30YR 0.53%

GNMA2 30YR 0.52%

Check overlap with more funds →

Side by side

IBB iShares Biotechnology ETF MBB iShares MBS ETF

Where it sits Thematic ETF Bond ETF

Issuer iShares iShares

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

Total return, 1 year +37.5% −0.8%

Its benchmark over the same days not measured −1.1% (SPMB)

Gap to its benchmark not measured +0.3 pts vs SPMB

Expense ratio 0.44% 0.04%

Holdings 245 10813

Net assets, IBB as of Oct 27, 2026 and MBB as of Oct 28, 2026 $11.0bn $35.5bn

IBB and MBB on the fields both publish, as of Oct 28, 2026. Source: ETFIQ.

Client brief · page 1 of 2 Report BR-82F5FD0925

IBB and MBB do different jobs. What does each one do in a portfolio?

What each follows. IBB follows Biotech and MBB follows Bloomberg U.S. MBS Index.
Holdings in common. 0% of the weight is in the same securities (holdings dated Oct 27, 2026).
One-year total return. Over 1 year to Oct 28, 2026 IBB returned +37.5% and MBB −0.8% with distributions reinvested, a gap of 38.3 points.

Data as of Oct 28, 2026.

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About each fund

IBB

By weight, 40% of IBB's portfolio is stocks that are also in the S&P 500; its active share against the S&P 500 is 99%. The top ten holdings are 50% of the fund across 245 positions, as published by its issuer for Oct 27, 2026. Over the year to Oct 28, 2026 the fund returned +37.5% with distributions reinvested.

MBB

MBB tracks an index of mortgage-backed securities. Over the year to Oct 28, 2026 it returned −0.8% with distributions reinvested, against −1.1% for its benchmark, the Bloomberg U.S. MBS Index. The prospectus expense ratio is 0.04% a year.

Questions people ask

Are IBB and MBB in the same category?: IBB is a thematic ETF and MBB is a bond ETF, so they do different jobs. The table compares what both publish: return, cost and holdings.
Which returned more over the last year, IBB or MBB?: In the year to Oct 28, 2026, with distributions reinvested, IBB returned +37.5% and MBB −0.8%.
Which is cheaper, IBB or MBB?: MBB is cheaper, by 0.40 percentage points a year. That is about $40 on $10,000 held for a year. Fees come from each fund's prospectus.

Other comparisons

IBB vs IEI IBB vs SCHP IBB vs MINT IBB vs TIP MBB vs XBI CGBL vs MBB MBB vs MUB BITO vs MBB

Where to next

IBB on its own →MBB on its own →Hold both: look the portfolio through →Rankings →IBB dividend history →IBB holdings →MBB dividend history →MBB holdings →Standards and sources →

Sources and dates

IBB and MBB filings on SEC EDGAR ↗

IBB prospectus with the expense ratio (SEC) ↗

iShares page for IBB ↗

MBB prospectus with the expense ratio (SEC) ↗

iShares page for MBB ↗

Links are sources, not endorsements. 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, IBB against MBB, data as of Oct 28, 2026. https://etfiq.com/compare/any/ibb-vs-mbb

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