Interesting move

My client is moving abroad to take up a new employment overseas. Some years ago he inherited substantial cash deposits on the death of some elderly relatives and rather than invest these into stocks and shares he has simply left them in various bank and building society deposit accounts and seems happy to continue to do so despite the best efforts of various advisers.

My concern is the tax treatment of the interest now that he is going abroad and – assuming that all goes to plan – is likely to become non-resident for UK tax purposes.

If the bank/building society interest is his only continuing source of income in the UK does this have to be declared on a self-assessment tax return?

Can he elect to have the interest paid gross or can he claim his UK personal allowances against this income?

This taxpayer is my first...