If one of your parents was a British citizen when you were born outside the UK, you may already be British by descent without needing to apply. Whether you are, and what your own children can pass on, depends on when you were born and how your parent got their citizenship.

Automatic citizenship by descent

You are usually British by descent automatically if, at your birth outside the UK:

your mother or father was a British citizen otherwise than by descent (born, adopted, registered or naturalised in the UK), or
your parent was a British citizen in Crown or similar service.

For births before 1 July 2006, parents' marital status mattered for fathers, and before 1983 citizenship generally passed only through fathers; later law has corrected much of this and registration routes exist for those affected.

The limit

Citizenship by descent does not normally pass to a further generation born abroad. If you are British by descent and your child is born outside the UK, your child is not automatically British. They may be able to register if you lived in the UK for three years before their birth, or if the family returns to live in the UK for three years.

Registration routes

Children of British citizens by descent born abroad, under section 3(2) or 3(5) of the British Nationality Act 1981.
People who would have been British but for historical unfairness, such as children of British mothers born before 1983 or of unmarried British fathers born before July 2006.
Adults with no other route may still have options under the discretionary provisions.

Proving it

A passport application is the usual way to confirm automatic citizenship. Where the chain of birth and citizenship records is incomplete, we trace and evidence it, including historic records of a parent's or grandparent's status.

What we do

We tell you whether you are already British, which of your children are, and which need an application, and we prepare registration applications with the documentary chain. Fees for registration vary by route; we confirm the current fee before you apply.