etf overlap · light overlap
VO vs CSPX overlap
15% of VO and CSPX is the same money, spread over 241 companies both funds hold.
Holdings as of September 30, 2026 · source: Vanguard (VO), iShares (CSPX) · How we measured all 1,431 pairs
- same money
- same companies, extra weight
- only in this fund
What only one of them gives you
Where each fund puts its money
VO and CSPX: what people ask
How much do VO and CSPX overlap?
15% by weight, as of September 30, 2026: light overlap. 241 companies appear in both funds; they make up 91% of VO and 15% of CSPX.
Which stocks do VO and CSPX both hold?
The largest shared positions are MPC, VLO, PSX, NEM and FTNT. Ranked by the smaller of the two weights, which is the part you would own twice.
Is it redundant to hold both VO and CSPX?
Out of every $100 split evenly between them, about $15 (half in each fund) buys identical positions. The rest is exposure only one of the two funds gives you: 30 names only in VO, 263 only in CSPX. Half in each behaves like 137 equally weighted stocks, against 206 for VO alone and 44 for CSPX alone. Whether that duplication is a problem depends on the mix you want; this is a description, not advice.
What is CSPX, next to VO?
CSPX is iShares Core S&P 500 UCITS ETF (ISIN IE00B5BMR087), an Irish-domiciled UCITS fund on the S&P 500 index. Next to VO, 15% of the money is the same, spread over 241 companies both hold, as of September 30, 2026.
Does the VO vs CSPX overlap apply to other tickers?
Yes. CSPX also trades as CSP1 (London, GBP), SXR8 (Xetra, EUR) and CSSPX (Borsa Italiana, EUR). Each is the same portfolio in another currency, on another exchange or paying its dividends out, so VO vs SXR8 also overlaps 15%.
How is ETF overlap calculated here?
For every company held by both funds we take the smaller of its two weights and add them up. The weights come from the full holdings files Vanguard and iShares publish, not a top-10 sample, and companies are matched by their ISIN so share classes stay apart. Sector overlap applies the same rule to the issuers' sector labels; "behaves like N equally weighted stocks" is one over the sum of the squared weights.
Weights come from each issuer's published holdings file and are matched company by company on their ISIN. Cash, futures and currency positions are left out. This page describes what the funds hold; it is not investment advice.