British Nationality Law - Dual Nationality and Dual Citizenship

Dual Nationality and Dual Citizenship

Since the British Nationality Act of 1948, there is in general no restriction, in United Kingdom law, on a British national being a citizen of another country as well. So, if a British national acquires another nationality, they do not automatically lose British nationality. Similarly, a person does not need to give up any other nationality when they become British, unless their first nationality requires it.

Different rules apply in the cases of British protected persons and certain British subjects. A person who is a British subject other than by connection with the Republic of Ireland loses that status on acquiring any other nationality or citizenship. Similarly, a British protected person is no longer a British protected person on acquiring any other nationality or citizenship. Although British Overseas citizens are not subject to loss of citizenship, British Overseas citizens may lose an entitlement to register as a British citizen under s4B of the 1981 Act if they acquire any other citizenship.

Many other countries, however, do not allow dual nationality (see Multiple citizenship). If a person has British nationality, and is also a national of a country that does not allow dual nationality, the authorities of that country may either regard the person as having lost that nationality or may refuse to recognize the British nationality. British nationals who acquire the nationality of a country that does not allow dual nationality may be required by the other country to renounce British nationality to retain the other citizenship.

Under international law, the Master Nationality Rule states that a State may not give diplomatic protection to one of its nationals in a country where the person also holds citizenship. For example, a person who is both British and American cannot receive diplomatic help from a British Consul in the United States.

A British person who acquired foreign citizenship by naturalisation before 1949 may have lost British nationality at the time. No specific provisions were made in the 1948 legislation for such former British subjects to acquire or otherwise resume British nationality, and hence such a person would not be a British citizen today. However, women who lost British nationality on marriage to a foreign man before 1949 were deemed to have reacquired British subject status immediately before the coming into force of the 1948 act.