I live/work in the UK but own some US shares held by US brokers that I've earned working for a USA company in UK. My broker sent me 1042-S and 1099 forms. Form 1099 reports $957 Federal Income Tax was withheld. Form 1042-S reports $246 as Tax withholding credit and mentions tax rate as 30%.
Why was I sent both 1042-S and 1099. Which amount is the right amount that has been withheld. Can I claim this in my UK returns that I file. If so, how? Is the tax rate 30% the correct tax rate? Will be glad if someone could guide me with the next steps?