QQQ vs CSPX overlap

54% by weight, as of September 24, 2026: heavy overlap. 85 companies appear in both funds; they make up 93% of QQQ and 55% of CSPX.

The largest shared positions are NVDA, AAPL, MSFT, AMZN and GOOGL. Ranked by the smaller of the two weights, which is the part you would own twice.

Out of every $100 split evenly between them, about $54 (half in each fund) buys identical positions. The rest is exposure only one of the two funds gives you: 16 names only in QQQ, 419 only in CSPX. Half in each behaves like 39 equally weighted stocks, against 32 for QQQ alone and 44 for CSPX alone. Whether that duplication is a problem depends on the mix you want; this is a description, not advice.

Partly: 54% of the money in CSPX and QQQ is the same, as of September 24, 2026. CSPX is iShares Core S&P 500 UCITS ETF (ISIN IE00B5BMR087), an Irish-domiciled UCITS fund on the S&P 500 index. European brokers generally don't sell US-listed ETFs such as QQQ to retail clients, because those funds publish no KID (the PRIIPs key information document); UCITS funds do.

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 QQQ vs SXR8 also overlaps 54%.

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 Invesco 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.