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Tax withheld by USA working in UK (Form 1042-S and Form 1099)
Why was I sent both 1042-S and 1099. Which amount is the right amount that has been withheld. Generally, each tax form you get will be about a separate income; for instance, you might get a 1099-DIV for dividends you earned from an investment and then a 1099-B for the profit or loss on selling that investment, in which case you'd report them both to the IRS. In this case, you've also had money withheld as a non-resident alien, which is why you've been issued a 1042-S. So you need to report both amounts to the IRS.