If your spouse or civil partner is a British citizen you may be able to apply for British citizenship by marriage. You must have lived in the UK for at least 3 years as a spouse/civil partner of a UK national before you apply for British citizenship. This way of acquiring British citizenship is called ‘naturalization’.

Eligibility

You need to meet the following to be able to apply for British citizenship by marriage under section 6 (2) of the British Nationality Act:
 You must be 18 or over;
 You must be free from immigration control i.e. hold Indefinite Leave to Remain;
 You must be married to or in a civil partnership with someone who is a British citizen;
 You must have lived for at least 3 years in the UK before the date of your application;
 You must prove your knowledge of English, Welsh, or Scottish Gaelic language
 You must pass the ‘life in the UK’ test;
 You must show that you are of a ‘good’ character;
 You must not have broken any UK immigration laws during your stay as a spouse in the UK;
 Not been out of the UK for 270 days in the last 3 years and no more than 90 days in the last years before the application;

You will not be able to apply for citizenship by marriage if your partner who was a British citizen has died, however you can apply for British Citizenship under section 6 (1) of the British Nationality Act 1981.

When can you apply?

You can apply for British Citizenship any time after you have one of the following:

 Indefinite leave to remain (ILR) in the UK
 ‘Settled status’ i.e. ‘indefinite leave to remain under the EU Settlement Scheme’)
 Indefinite leave to enter the UK (permission to move to the UK permanently from abroad)

You must have been physically present in the UK exactly 3 years before your application was received by the Home Office. If you apply online the Home Office will receive the application on the same day but if you apply by post it will take a few days to be received by the Home Office.

However, the Home Office may consider special circumstances such as the following:

 Your health conditions or travel restrictions did not allow you to live in the UK at the start of the 3-year period
 You were asked to leave the UK during the 3 years but later on, this decision was overturned

How to apply?

You can apply for British citizenship by marriage yourself or through a representative or an agent.

Applying yourself

If you apply online yourself, you can upload the application online. You will be asked to make an appointment at the UK Visa and Citizenship Application Service (UKVCAS) point to submit your biometrics (your fingerprints and photo). You can also submit your documents at the UKVCAS point along with your biometrics.
If you are applying from the Channel Islands, the Isle of Man, or a British overseas territory you need to send the application by post or in person. Once you have applied by the post you will be informed where to submit your biometric information.

Applying through an agent or representative

You can also apply through an agent or representative (a private company or an individual) registered with the Office of the Immigration Services Commissioner (OISC). You can also apply through a solicitor or barrister not registered with the OISC.

However, they must be registered with one of the following organizations:

 General Council of the Bar
 Law Society of England and Wales
 Chartered Institute of Legal Executives
 Faculty of Advocates
 Law Society of Scotland
 General Council of the Bar of Northern Ireland
 Law Society of Northern Ireland

How long does it take to get a decision?

You should get your decision in 6 months. Depending on your circumstances it may take longer as well.