British citizenship by naturalisation: who is eligible and how to apply

What is British citizenship by naturalisation?

If you have been granted indefinite leave to remain (ILR), you can apply for British citizenship. This process is known as naturalisation and typically marks the final step in your immigration journey.

What is the difference between indefinite leave to remain and British citizenship?

Both indefinite leave to remain and British citizenship allow you to live and work in the United Kingdom indefinitely, free from immigration time restrictions. You can also access public services and healthcare with both.

However, British citizenship gives you additional rights, such as:

• the right to vote;

• the ability to hold public office;

• eligibility for a British passport.

You may also lose your indefinite leave to remain status if you have been absent from the UK for more than two years, whereas citizenship is permanent.

Do I need to apply for citizenship?

No, citizenship is entirely optional and it comes down to personal choice.

If you are considering naturalising as a British citizen, you must check that your country of origin allows dual nationality; otherwise, you may lose your existing citizenship.

British citizenship through naturalisation

Naturalisation, unlike British citizenship acquired through birth or a British parent, is not an automatic entitlement. It is seen as a privilege and not a right, and applications are granted on a discretionary basis.

Section 6(2) of the British Nationality Act 1981 sets out the requirements for naturalising as a British citizen if you are married to a British citizen. If you are not married to a British citizen then section 6(1) applies, however this article will focus solely on spouses of British citizens.

British citizenship eligibility requirements for those married to a British citizen

If you are at least 18 years old, hold indefinite leave to remain or a right of permanent residence in the UK, and are married to a British citizen then you may be eligible to naturalise as a British citizen immediately. You must be of sound mind and understand that you are applying for British citizenship.

Residency requirement (3-year rule)

You must have been physically present in the UK three years prior to submitting your application for British citizenship. This is calculated as the day after submission minus three years. For example, if you submit your application on 1 December 2026, you must have been physically present in the UK on 2 December 2023.

In exceptional circumstances, such as illness, your application may still be granted. Further, the decision maker may establish a later date to allow you to meet the requirement and will consider your application on, or after that date.

Absence requirements

You must not have been absent from the UK for more than 270 days in the three years prior to the date of application. In addition, you must not have been absent for more than 90 days in the 12 months prior to the date of application.

Absences can be assessed through passports, travel documents, Home Office records or employers’ letters, tax and National Insurance letters. You may still be eligible if you exceed the absence threshold and our team can help determine whether your application is likely to succeed.

Free from immigration control

You must be free from immigration time restrictions. You will meet this condition if you hold indefinite leave to remain, settled status under the EU Settlement Scheme, or you have a right to abode in the UK. Irish citizens are also considered settled from the date of arrival in the UK. You can prove your status digitally (eVisa) though your online UKVI account.

You will not meet this requirement if you are on immigration bail, in immigration detention or have breached immigration laws in the three years before making the application.

Good character requirement

To be eligible for naturalisation and take the next steps from your status as indefinite leave to remain, you must be of good character. This means you must observe UK laws and show respect for the right and freedom of its citizens. Good character looks at your background including criminality, terrorism, notoriety, deception, dishonesty, and financial soundness.

You can provide evidence of your community ties, charitable work, and positive contributions to society.

English language requirement

You must meet the English language requirement at minimum level B1 CEFR. You will automatically meet this requirement if you are a national of a majority English speaking country, for example, the United States of America or Canada.

You will also meet the requirement if you have a UK degree or obtained a degree outside the UK that was taught or researched in English. Alternatively, you can pass an English language test from an approved Home Office test provider. If you passed an English test as part of application for the indefinite leave to remain, you can use the same test qualification.

‘Life in the UK’ test

To conclude the process, you will also need to pass the Government ‘Life in the UK’ test (£50). You are exempt from sitting this if you are under 18, over 65, have passed it in a previous application (e.g., indefinite leave to remain application) or you have a long-term physical or mental condition.

Children and British citizenship

Your child will automatically become a British citizen if they were born in the UK to a British or settled parent. Please contact our team or read our article on children and their rights to British citizenship for more information.

Costs and processing times

The application costs £1,839. You will normally receive a decision within six months, although some applications may take longer.

Once you have naturalised as a British citizen, you will not automatically be issued with a British passport. You must apply for this separately and pay an additional passport fee of £102.