I thought this might be helpful to people on this forum, but it is not necesarilly tax-related.
I am a USC living in England, and it has been difficult to get credit due to not being on the electoral roll. I do not want credit so that I can live beyond my means, but to build my credit history to aid in getting a mortgage eventually.
I got a barclaycard initial when I was first here, and now, 3 years in, I am still unable to get the best credit cards here in the UK. I did find one loophole though:
I have been an American Express customer in the US since 2004, and I have a 'blue' card. I was on the Amex UK site, and applied for a UK card as a current cardholder on a whim a few months ago. I put my US Amex number into the application and submitted it. I didn't hear anything for a few weeks, but eventually a shiny new American Express Platinum cashback card arrived in the mail with a £2,500 limit. This card is currently the best cashback card on the market, with 5% cashback for the first few months on all purchases, capped at £100, then .5%-1.5% thereafter.
I thought this might be helpful to others in the same boat. Granted, an American Express card is not accepted everywhere, but its acceptance is higher than I thought, especially at any national store on the high street. The only place I have not had luck was at Clark's yesterday.
Good luck!