British Nationals (Overseas) can be registered under section 4B of the British Nationality Act 1981.
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The Borders, Citizenship and Immigration Bill, which received Royal Assent on 21 July 2009, introduced certain changes to British nationality law.
5 March 2013
13 December 2016
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Foreign & Commonwealth Office
British nationals overseas
Don’t include personal or financial information like your National Insurance number or credit card details.