I am working in the US on an H-1B visa. I have paid full US federal and California state taxes for the last 4 years.

Surely I am exempt from UK taxation under the current treaty. However, the UK tax authorities don't think so!

I don't believe you are liable to tax in the UK on income earned without the UK.

See: Residence and Domicile Taxation in the United Kingdom - Wikipedia, the free encyclopedia

Five Rings:

In the past, I would agree with you without reservation.

However, I have been getting reports from clients in the U.K. that the government there is beginning to take the same attitude towards their citizen's world-wide income that the U.S. government has long held. i.e. ALL world-wide income of U.K. citizens is subject to U.K. income taxes.

This may be something we need to investigate more thoroughly.

Yes. They are trying to squeeze out as much as they can.

See: Tax Definitions

Well, that is about as clear as mud!

And I thought U.S. tax regulations were overly complex!