Data as of Sep 12, 2026. Both funds on the fields they both publish, from the same sources.
SPY vs VO: how they differ
SPY and VO hold 15% of their weight in the same names, and SPY returned more over the year.
SPDR S&P 500 ETF Trust and Vanguard Mid-Cap Index Fund.
What they hold in common
By the books each fund has filed, SPY and VO hold 15% of their money in the same securities at the same weight.
| Holding | SPY | VO |
|---|---|---|
| Western Digital Corp. | 0.34% | 1.07% |
| Vertiv Holdings Co. | 0.20% | 1.23% |
| Quanta Services, Inc. | 0.17% | 1.05% |
| Howmet Aerospace, Inc. | 0.17% | 1.04% |
| Newmont Corp. | 0.15% | 0.48% |
| Cummins, Inc. | 0.15% | 0.95% |
| Fortinet, Inc. | 0.15% | 0.46% |
| Williams Cos., Inc. (The) | 0.14% | 0.44% |
| Datadog, Inc. | 0.13% | 0.84% |
| Constellation Energy Corp. | 0.12% | 0.78% |
| Robinhood Markets, Inc. | 0.12% | 0.77% |
| Coherent Corp. | 0.12% | 0.75% |
| Only in SPY | Only in VO |
|---|---|
| NVIDIA Corp. 7.52% | Seagate Technology Holdings PLC 1.05% |
| Apple, Inc. 6.59% | Bloom Energy Corp 0.79% |
| Microsoft Corp. 4.30% | Cloudflare Inc 0.76% |
| Amazon.com, Inc. 3.62% | Royal Caribbean Cruises Ltd 0.74% |
| Alphabet, Inc. 3.25% | CRH PLC 0.69% |
| Broadcom, Inc. 2.77% | Rocket Lab Corp 0.57% |
| Alphabet, Inc. 2.59% | TE Connectivity PLC 0.57% |
| Micron Technology, Inc. 2.02% | Cheniere Energy Inc 0.49% |
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.
| SPY SPDR S&P 500 ETF Trust | VO Vanguard Mid-Cap Index Fund | |
|---|---|---|
| Where it sits | Core index fund | Core index fund |
| Issuer | State Street | Vanguard |
| What it is | S&P 500, book from IVV | Mid-Cap |
| Total return, 1 year | +17.5% | +12.0% |
| S&P 500 over the same days | +17.5% | +17.5% |
| Gap to the S&P 500 | 0.0 pts | −5.5 pts |
| Expense ratio | 0.09% | 0.03% |
| Already in the S&P 500 | 100.0% | 91.4% |
| Holdings | 504 | 282 |
SPY in plain words
SPY is an index equity fund tracking the S&P 500. Over the year to Sep 11, 2026 it returned +17.5% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.09% a year. By its holdings filed for Jun 30, 2026, 100% of the fund by weight is stocks the S&P 500 also holds, across 504 positions, with the top ten at 36.4%.
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, SPY or VO?
- In the year to Sep 12, 2026, with distributions reinvested, SPY returned +17.5% and VO returned +12.0%, so SPY returned more. One year is one year; the longer windows are in the table.
- Which is cheaper, SPY or VO?
- SPY charges 0.09% a year and VO charges 0.03%, so VO is cheaper. Fees come from each fund's prospectus.
- How much do SPY and VO overlap with the S&P 500?
- By their latest filed holdings, 100% of SPY and 91% of VO by weight is stocks the S&P 500 already holds. Between the two funds, 15% 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, SPY against VO, data as of Sep 12, 2026. https://etfiq.com/compare/any/SPY-VO Free to use with attribution; the underlying files are at Open data.
A comparison is not a recommendation. Standards and sources