Data as of Sep 12, 2026. Both funds on the fields they both publish, from the same sources.
IWO vs VO: how they differ
IWO and VO hold 0% of their weight in the same names, and IWO returned more over the year.
iShares Russell 2000 Growth ETF and Vanguard Mid-Cap Index Fund.
What they hold in common
By the books each fund has filed, IWO and VO hold 0% of their money in the same securities at the same weight.
| Only in IWO | Only in VO |
|---|---|
| Moog, Inc. 0.73% | Vertiv Holdings Co 1.23% |
| BrightSpring Health Services, Inc. 0.68% | Western Digital Corp 1.07% |
| MaxLinear, Inc. 0.67% | Seagate Technology Holdings PLC 1.05% |
| Argan, Inc. 0.66% | Quanta Services Inc 1.05% |
| JFrog Ltd. 0.60% | Howmet Aerospace Inc 1.04% |
| Krystal Biotech, Inc. 0.58% | Cummins Inc 0.95% |
| ESCO Technologies, Inc. 0.56% | Datadog Inc 0.84% |
| FirstCash Holdings, Inc. 0.54% | Bloom Energy Corp 0.79% |
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.
| IWO iShares Russell 2000 Growth ETF | VO Vanguard Mid-Cap Index Fund | |
|---|---|---|
| Where it sits | Core index fund | Core index fund |
| Issuer | iShares | Vanguard |
| What it is | Russell 2000 Growth | Mid-Cap |
| Total return, 1 year | +17.0% | +12.0% |
| S&P 500 over the same days | +17.5% | +17.5% |
| Gap to the S&P 500 | −0.5 pts | −5.5 pts |
| Expense ratio | 0.24% | 0.03% |
| Already in the S&P 500 | 0.0% | 91.4% |
| Holdings | 1133 | 282 |
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 Jun 30, 2026, 0% of the fund by weight is stocks the S&P 500 also holds, across 1133 positions, with the top ten at 6.1%. It sat 7.1% below its high of Aug 14, 2026 on Sep 11, 2026.
VO in plain words
VO is an index equity fund tracking the Mid-Cap. Over the year to Sep 11, 2026 it returned +12.0% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.03% a year. By its holdings filed for Jun 30, 2026, 91% of the fund by weight is stocks the S&P 500 also holds, across 282 positions, with the top ten at 9.6%. It sat 4.1% below its high of Aug 14, 2026 on Sep 11, 2026.
Questions people ask
- Which returned more over the last year, IWO or VO?
- In the year to Sep 12, 2026, with distributions reinvested, IWO returned +17.0% and VO returned +12.0%, so IWO returned more. One year is one year; the longer windows are in the table.
- Which is cheaper, IWO or VO?
- IWO charges 0.24% a year and VO charges 0.03%, so VO is cheaper. Fees come from each fund's prospectus.
- How much do IWO and VO overlap with the S&P 500?
- By their latest filed holdings, 0% of IWO and 91% of VO 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 VO, data as of Sep 12, 2026. https://etfiq.com/compare/any/IWO-VO Free to use with attribution; the underlying files are at Open data.
A comparison is not a recommendation. Standards and sources