Meshfolio
FUND OVERLAP · LOOK-THROUGH

SPY vs VOO: how much do they really overlap?

SPY (SPDR S&P 500 ETF Trust, tracking the S&P 500) and VOO (Vanguard S&P 500 ETF, tracking the S&P 500) overlap by roughly 96% by weight. 10 of SPY's top 10 holdings also appear in VOO. A 50/50 blend of the two behaves like about 51 equally-weighted bets (diversification grade B). In short, the two funds hold nearly the same stocks in nearly the same proportions — owning both is largely redundant.

96%
weight overlap
10/10
of SPY’s top 10 also in VOO
B
50/50 blend grade
~51
real bets in a 50/50 blend
You think SPY and VOO are two funds. By weight they lean on the same names: both hold NVIDIA Corporation (NVDA)7.4% of SPY and 7.9% of VOO. Hold both and NVDA just becomes a bigger single bet, not a more diversified one.

The same companies, in both funds

These 25 holdings appear in both SPY and VOO. The weight columns show how much of each fund each name represents.

Holdingin SPYin VOO
NVDA NVIDIA Corporation7.38%7.89%
AAPL Apple Inc.6.47%7.05%
MSFT Microsoft Corporation4.28%5.14%
AMZN Amazon.com, Inc.3.68%4.07%
GOOGL Alphabet Inc.3.24%3.41%
AVGO Broadcom Inc.2.76%3.26%
GOOG Alphabet Inc.2.60%2.71%
META Meta Platforms, Inc.1.93%2.13%
TSLA Tesla, Inc.1.81%1.89%
MU Micron Technology, Inc.2.02%1.68%
LLY Eli Lilly and Company1.52%1.35%
BRK.B Berkshire Hathaway Inc.1.42%1.34%
AMD Advanced Micro Devices, Inc.1.38%1.29%
JPM JPMorgan Chase & Co.1.38%1.16%
XOM Exxon Mobil Corporation0.88%0.93%

+ 10 more shared holdings.

Only in SPY

SPDR S&P 500 ETF TrustUS large-cap. Its biggest holdings that VOO doesn’t have:

Every listed SPY holding is also in VOO.

Only in VOO

Vanguard S&P 500 ETFUS large-cap. Its biggest holdings that SPY doesn’t have:

MA Mastercard Inc. Class A0.62%
ORCL Oracle Corp.0.59%
NFLX Netflix Inc.0.56%
PLTR Palantir Technologies Inc. Class A0.55%
UNH UnitedHealth Group Inc.0.53%
CVX Chevron Corp.0.53%
GE General Electric Co.0.52%
PG Procter & Gamble Co.0.51%

So — nearly identical. Should you hold both?

SPY and VOO hold nearly the same stocks in nearly the same proportions — owning both is largely redundant. If you already hold SPY, adding VOO mostly increases your bet on the names they share rather than spreading it — a 50/50 blend still behaves like only ~51 equal positions, with the top 10 alone at 38% and the Magnificent Seven at 33%.

Holdings as of — SPY: Jun 29, 2026 (State Street Global Advisors); VOO: May 31, 2026 (Vanguard). Refreshed monthly. Overlap is measured across each fund’s largest holdings (top 50); the diffuse long tail barely moves the math.

See this for YOUR whole portfolio, free →

SPY vs VOO — FAQ

How much do SPY and VOO overlap?
SPY and VOO overlap by approximately 96% measured by portfolio weight — that is the share of the smaller fund's holdings (by weight) that also sit inside the other. 10 of SPY's 10 largest holdings are also held by VOO. They share 25 of their listed top holdings in total.
Is it redundant to hold both SPY and VOO?
Because they hold nearly the same stocks in nearly the same proportions — owning both is largely redundant, holding both is largely redundant — you mostly duplicate the same megacaps and concentrate rather than diversify. A 50/50 blend has an effective 51 positions and a B diversification grade.
What does VOO hold that SPY doesn't?
VOO's largest holdings that SPY doesn't hold include MA, ORCL, NFLX, PLTR, UNH. Its category is US large-cap, versus SPY's US large-cap.
Which is more concentrated, SPY or VOO?
SPY's top 10 holdings are 71% of its listed weight; VOO's are 61%. The more concentrated fund leans harder on its largest names.

Related comparisons