Data as of Sep 13, 2026. Both funds on the fields they both publish, from the same sources.
IVV vs VO: how they differ
IVV and VO hold 0% of their weight in the same names, and IVV returned more over the year.
iShares Core S&P 500 ETF and Vanguard Mid-Cap Index Fund.
What they hold in common
By the books each fund has filed, IVV and VO hold 0% of their money in the same securities at the same weight.
| Only in IVV | Only in VO |
|---|---|
| NVIDIA 8.06% | Vertiv Holdings Co 1.23% |
| APPLE 7.31% | Western Digital Corp 1.07% |
| MICROSOFT 5.58% | Seagate Technology Holdings PLC 1.05% |
| AMAZON.COM INC 3.76% | Quanta Services Inc 1.05% |
| ALPHABET CLASS A 2.98% | Howmet Aerospace Inc 1.04% |
| BROADCOM INC 2.61% | Cummins Inc 0.95% |
| ALPHABET CLASS C 2.38% | Datadog Inc 0.84% |
| META PLATFORMS CLASS A 2.16% | 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 and Sep 10, 2026.
| IVV iShares Core S&P 500 ETF | VO Vanguard Mid-Cap Index Fund | |
|---|---|---|
| Where it sits | Core index fund | Core index fund |
| Issuer | iShares | Vanguard |
| What it is | S&P 500 | Mid-Cap |
| Total return, 1 year | +17.6% | +12.0% |
| S&P 500 over the same days | +17.5% | +17.5% |
| Gap to the S&P 500 | +0.1 pts | −5.5 pts |
| Expense ratio | 0.03% | 0.03% |
| Already in the S&P 500 | 100.0% | 91.4% |
| Holdings | 505 | 282 |
IVV in plain words
IVV is an index equity fund tracking the S&P 500. Over the year to Sep 11, 2026 it returned +17.6% 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 Sep 10, 2026, 100% of the fund by weight is stocks the S&P 500 also holds, across 505 positions, with the top ten at 38.1%.
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. 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, IVV or VO?
- In the year to Sep 13, 2026, with distributions reinvested, IVV returned +17.6% and VO returned +12.0%, so IVV returned more. One year is one year; the longer windows are in the table.
- Which is cheaper, IVV or VO?
- IVV charges 0.03% a year and VO charges 0.03%, so IVV is cheaper. Fees come from each fund's prospectus.
- How much do IVV and VO overlap with the S&P 500?
- By their latest filed holdings, 100% of IVV 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, IVV against VO, data as of Sep 13, 2026. https://etfiq.com/compare/any/ivv-vs-vo Free to use with attribution; the underlying files are at Open data.
A comparison is not a recommendation. Standards and sources