You may occasionally look at an ETF’s holdings and see something like “SPY 09/18/2026 10.01 C” or “SPX US 06/18/26 C7430”.
These are call options on SPY and SPX.
Why do ETFs use one versus the other? (many reasons, but I’ll focus on tax here)
And how do we keep them straight?
Below is an idiotproof mnemonic for remembering which is which… and a side-by-side comparison of the tax attributes.