UKAbroad

Dear HMRC, I am a non-UK resident. I live abroad in the USA. I receive a very small royalty payment from the UK every year and less than £20 is deducted at source for UK withholding tax. I claim this back manually by mailing in paper forms SA100 and R43 at the same time. My question to you is, can I do this online or does this always need to be done manually? If you can do it online do you have to do the SA100 first and then do the R43 right after, or is there another process to sequence these two forms together? I appreciate your help. Thank you.