They are essentially the same (SPY is larger) and target the same index (S&P 500). But because XUS holds its stock interests via another ETF and not directly, there is a minor additional amount of withholding taxes. That is a small negative. But on the positive side, XUS is a Canadian-domiciled fund and thus does not need to be reported as foreign content for tax purposes, and also does not get captured uner US estate law taxation. Dividends are automatically converted to C$ with XUS, which is a small negative as brokers will change a f/x conversion fee (this will not be noticed and is taken at source). We would continue to prefer buying US securities in US dollar accounts.
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