Data as of Sep 13, 2026. Both funds on the fields they both publish, from the same sources.
IWO vs XBI: how they differ
IWO and XBI hold 0% of their weight in the same names, and XBI returned more over the year.
iShares Russell 2000 Growth ETF and State Street(R) SPDR(R) S&P(R) Biotech ETF.
What they hold in common
By the books each fund has filed, IWO and XBI hold 0% of their money in the same securities at the same weight.
| Only in IWO | Only in XBI |
|---|---|
| MOOG INC CLASS A 0.69% | MODERNA INC 2.87% |
| GLAUKOS 0.65% | TWIST BIOSCIENCE CORP 1.81% |
| JFROG 0.64% | HALOZYME THERAPEUTICS INC 1.47% |
| BRIGHTSPRING HEALTH SERVICES INC 0.62% | NATERA INC 1.46% |
| FIRSTCASH HOLDINGS INC 0.62% | KYMERA THERAPEUTICS INC 1.45% |
| BRINKER INTERNATIONAL INC 0.61% | TRAVERE THERAPEUTICS INC 1.40% |
| INTERDIGITAL INC 0.60% | ROIVANT SCIENCES LTD 1.39% |
| KRYSTAL BIOTECH 0.59% | ORUKA THERAPEUTICS INC 1.38% |
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.
| IWO iShares Russell 2000 Growth ETF | XBI State Street(R) SPDR(R) S&P(R) Biotech ETF | |
|---|---|---|
| Where it sits | Core index fund | Core index fund |
| Issuer | iShares | State Street |
| What it is | Russell 2000 Growth | SPDR S&P Biotech |
| Total return, 1 year | +17.0% | +64.0% |
| S&P 500 over the same days | +17.5% | +17.5% |
| Gap to the S&P 500 | −0.5 pts | +46.5 pts |
| Expense ratio | 0.24% | 0.35% |
| Already in the S&P 500 | 0.0% | 8.5% |
| Holdings | 970 | 154 |
IWO in plain words
IWO is an index equity fund tracking the Russell 2000 Growth. Over the year to Sep 11, 2026 it returned +17.0% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.24% a year. By its holdings filed for Sep 10, 2026, 0% of the fund by weight is stocks the S&P 500 also holds, across 970 positions, with the top ten at 6.2%. It sat 7.1% below its high of Aug 14, 2026 on Sep 11, 2026.
XBI in plain words
XBI is an index equity fund tracking the SPDR S&P Biotech. Over the year to Sep 11, 2026 it returned +64.0% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.35% a year. By its holdings filed for Sep 10, 2026, 8% of the fund by weight is stocks the S&P 500 also holds, across 154 positions, with the top ten at 15.9%. It sat 9.6% below its high of Feb 8, 2021 on Sep 11, 2026.
Questions people ask
- Which returned more over the last year, IWO or XBI?
- In the year to Sep 13, 2026, with distributions reinvested, IWO returned +17.0% and XBI returned +64.0%, so XBI returned more. One year is one year; the longer windows are in the table.
- Which is cheaper, IWO or XBI?
- IWO charges 0.24% a year and XBI charges 0.35%, so IWO is cheaper. Fees come from each fund's prospectus.
- How much do IWO and XBI overlap with the S&P 500?
- By their latest filed holdings, 0% of IWO and 8% of XBI by weight is stocks the S&P 500 already holds. Between the two funds, 0% of their books are the same securities at the same weight.
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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.
Cite this page. ETFIQ, IWO against XBI, data as of Sep 13, 2026. https://etfiq.com/compare/any/iwo-vs-xbi Free to use with attribution; the underlying files are at Open data.
A comparison is not a recommendation. Standards and sources