I have a client who performed in the UK in the autumn of 2019 and was given a Foreign Entertainers Unit certificate listing the payments made and UK tax deducted at source, of course in pounds. Client had only one employer for the UK.
I'm aware that the UK has a very robust withholding system compared to ours, and as such few people have to file tax returns in the UK. However, is there some way to know whether my client would be required to file, so that I can at least let them know and/or help find a UK specialist to file the return? Everything I could read on HMRC website was as clear as mud and seemed to dither without actually coming out and saying when a return is required.