Dual citizenship (also known as dual nationality) is allowed in the UK. This means you can be a British citizen and also a citizen of other countries.
You do not need to apply for dual citizenship. You can apply for foreign citizenship and keep your British citizenship.
Many countries do not accept dual citizenship. Check with the country’s consulate or embassy in the UK to find out about that country’s laws on dual nationality.
Apply for British citizenship
To get British citizenship in the UK, check how to apply in your situation.
As a dual national you cannot get diplomatic help from the British government when you are in the other country where you hold citizenship.
For example, if you hold both British and Chinese citizenship you cannot get diplomatic help from the UK when you’re in China.
Dual citizenship, marriage and children
You do not automatically become a British citizen when you marry a person from the UK. You need to apply as the spouse of a British citizen.
In some countries, a married person is automatically counted as having their partner’s nationality. Children may also automatically have a parent’s nationality even if they were born abroad.
Check with the country’s consulate or high commission in the UK to find out about that country’s laws on dual nationality.