CSPX vs VOO: how much do they overlap?

iShares Core S&P 500 UCITS ETF (USD Acc) (CSPX) · Vanguard S&P 500 ETF (VOO)

CSPX and VOO overlap by 89.5% by portfolio weight. In practical terms, about 10.5% of the smaller-weighted exposure is different between the two funds. They share 487 stocks; the largest shared position is Nvidia Corp (NVDA), contributing 7.58% to the overlap.

89.5%

overlap by weight · 487 shared holdings

CSPX: 503 holdings (as of 2026-08-04) · VOO: 504 holdings (as of 2026-03-31)

Holdings dates reflect the latest official files available for each issuer. Some issuers publish daily files; others are represented by periodic SEC filings. Analysis template updated 2026-08-04.

Note: the two funds' latest official filings have different dates, which can understate overlap slightly for funds tracking similar indexes.

High overlap

What this means

CSPX and VOO are largely the same portfolio. Holding both adds little diversification — most dollars end up in the same underlying stocks.

Overlap by weight sums the smaller of the two funds' weights for every stock they both hold — it answers "how much of my money is in the same stocks either way?" See methodology.

Top shared holdings

CompanyTickerin CSPXin VOO
Nvidia Corp NVDA 7.7% 7.58%
Apple Inc AAPL 6.82% 6.66%
Microsoft MSFT 5.49% 4.91%
Amazon.Com Inc AMZN 4.08% 3.64%
Alphabet Class A GOOGL 3.32% 2.99%
Broadcom Inc AVGO 2.97% 2.62%
Alphabet Class C GOOG 2.66% 2.4%
Meta Platforms Class A META 1.94% 2.24%
Tesla Inc TSLA 1.38% 1.87%
Jpmorgan Chase & Co JPM 1.44% 1.34%

FAQ

How much do CSPX and VOO overlap?

CSPX and VOO have a 89.5% overlap by weight, sharing 487 holdings (out of 503 in CSPX and 504 in VOO), based on official issuer holdings as of 2026-08-04.

What does 89.5% overlap mean?

CSPX and VOO are largely the same portfolio. Holding both adds little diversification — most dollars end up in the same underlying stocks.

Which stocks do CSPX and VOO both hold?

The largest shared positions are Nvidia Corp, Apple Inc, Microsoft, Amazon.Com Inc, Alphabet Class A. The full list of top shared holdings with weights in each fund is shown on this page.

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