British Citizenship Routes

Most adults living in the UK become British by naturalisation: after five years' residence and, usually, 12 months with indefinite leave to remain or settled status, you apply online to the Home Office. Partners of British citizens and children follow separate rules.

Naturalisation and the partner route

For naturalisation, you must be over 18, have lived in the UK for at least 5 years, and have held indefinite leave to remain, settled status under the EU Settlement Scheme or indefinite leave to enter for the last 12 months. You must also prove your knowledge of English, Welsh or Scottish Gaelic, have passed the Life in the UK Test, intend to continue living in the UK and be of good character. You should not have spent more than 450 days outside the UK during the 5 years before applying, or more than 90 days in the last 12 months, and you must have been in the UK exactly 5 years before the day the Home Office receives your application.

Partners of British citizens apply under a different section of the law. If you are married to or in a civil partnership with a British citizen, you need 3 years' residence rather than 5, with no more than 270 days abroad in those 3 years and no more than 90 in the last 12 months. You still need indefinite leave to remain, settled status or indefinite leave to enter, but you do not have to wait 12 months after getting it. The language, Life in the UK Test and good character requirements are the same. Irish citizens and some people with pre-settled status have their own routes, set out on GOV.UK.

Applying, referees and children

You fill in the application form online, then book an appointment at a UK Visa and Citizenship Application Services (UKVCAS) service point to give your fingerprints and a photo. Documents can be uploaded or scanned at the appointment. A decision usually comes within 6 months. Your application must be endorsed by 2 referees who have each known you for at least 3 years. One can be of any nationality but must be a professional person, such as a civil servant, a minister of religion or a member of a professional body; the other must hold a British citizen passport and be either a professional person or over 25. Referees cannot be related to you or to each other, or be your solicitor or agent.

Children are not included in a parent's application. You apply separately to register a child as a British citizen if they were born outside the UK, or in the UK before you got indefinite leave to remain. A child born in the UK after a parent was granted indefinite leave to remain may already be British automatically.

The ceremony, dual nationality and advice

If your application succeeds, adults must attend a citizenship ceremony, usually arranged by the local council, within 3 months of receiving the Home Office invitation. You take an oath of allegiance, or an affirmation if you prefer not to swear by God, and a pledge, and you receive your certificate of British citizenship at the end of the ceremony. Children under 18 do not have to attend. With the certificate you can then apply for a British passport.

The UK allows dual nationality, but not every country does, so check with your other country's embassy or consulate before you apply. If you want help, use only a regulated adviser: immigration advisers must be registered with the Immigration Advice Authority (IAA), which replaced the Office of the Immigration Services Commissioner (OISC), or be a solicitor or barrister regulated by a recognised professional body.

Before you start, read the GOV.UK guidance for your route, check your absences against the limits, line up your referees and gather your evidence. Current fees and processing options are listed on GOV.UK.