If you have Indefinite Leave to Remain in the UK, EU settled status or permanent residence you may be considering applying to naturalise as a British citizen. To apply, you will need to complete a naturalisation application form, along with supplying supporting evidence and satisfying other criteria such as language proficiency and life in the UK knowledge.       

Form AN

In most cases the naturalisation application form you need to use to make your citizenship application is Form AN. In the past you had to submit your application form and supplementary original documents in the post but now you can complete the naturalisation form online.

The Home Office will use the information you provide in the Form AN to assess your eligibility for naturalisation. The form has a number of different sections and must be filled out correctly or your application will be refused. We look at the main sections you will need to complete:

Personal details

The first section of the naturalisation form to complete is your personal details. In this section you will need to provide key information such as:

  • Current and previous names and supply supporting evidence to prove this - such as marriage certificate, passport or deed poll.
  • Details of your current address and addresses you have lived at over the past 5 years, including accurate dates of when you lived there.

Knowledge of language and life in the UK

In this section you will be required to confirm that you fulfil certain essential criteria.

Life in the UK

Before completing your naturalisation application form you will normally need to pass the Life in the UK test. You can take the test at any time before you apply.

You are exempt if you are over 65 or under 18, you can't take the test for medical reasons or you already passed it when applying for indefinite leave to remain. If you have a medical reason for not taking the test you must have a letter or form from your doctor confirming the reason why. 

English requirements  

You will also need to confirm your proficiency in English. You either hold a speaking and listening qualification in English at B1 CEFR or higher, hold a degree from a UK university or hold a degree that was taught or researched in English.

You are exempt from these requirements if you are over 65 or under 18, your home country is on the list of exempt nationalities or if you have a medical reason that stops you taking the test.

With your Form AN you must submit evidence of your proficiency through evidence of passing the test, a degree certificate, or evidence of another approved language qualification.

Family details

You will be required to provide details of your parents, their place of birth and date of birth. You will also have to give details of your partner, their nationality, address and address history. If you have previous marriages these details must also be supplied.

Employment history

In this section you will be asked to provide current employment details and your UK employment history for the past ten years including employer names and addresses and the dates you worked there.

Residence requirements

This is one of the most involved and important parts of the naturalisation application form. You must enter comprehensive details of all absences from the UK over the past 5 years (or 3 years if married or in a civil partnership with a UK citizen). Information required includes the country visited, reason for visit and the dates. It is vital this information is accurate and verifiable.

Good character

This is another key section. The Home Office case worker will assess whether you are of good character and will use this as a basis to check your character with other authorities such as the police and security service.

You will need to declare any criminal convictions, civil judgements or penalties, involvement in war crimes, crimes against humanity, or terrorism either in the UK or any other country.


This section of your naturalisation application form should be completed by your referees and must be completed correctly or your application will be rejected. Your referees must be two people over 25 years of age who have known you for at least three years. They must be professionals e.g. a police officer, chemist, or doctor and at least one must be a UK citizen. Both of must sign the single page of the form with a passport picture of you on for your application to be accepted.

Biometric information

When you apply for UK citizenship you will need to provide biometric information - your fingerprints and photo. If you have not you will be told how to provide this information after you have submitted your application. The current cost for this is £19.20.

The MN1 Form

You may be able to register a child under 18 as a British citizen if they qualify through birth or adoption. If you want to register your child you will need to do this using the Form MN1 not the Form AN.

With the form you will need to submit documents such as a passport and birth certificate to support their application.

If you are registering a child over the age of 10, they must be of ‘good character’. That means they will need to show respect for the rights and freedoms of the UK, its laws and fulfil their duties as a UK citizen. You must give any details of criminal convictions your child holds either in the UK or abroad.

Your child will also need to provide biometric information to verify their identity. If your child is under 6, they will only need to provide a photo not their fingerprints

Avoiding costly errors

It takes careful preparation to complete a naturalisation application form. The form is extensive and gathering the supporting evidence is typically demanding on applicants. The application fee is also non-refundable. If you fail to complete the form correctly, you not only risk your application for citizenship being refused, but you will also lose the application fee. If you are deemed to knowingly give false information it is considered a criminal offence and you could be given a 3 month prison sentence or a fine of up to £5000.

For these reasons, many applicants engage the services of a legal expert to ensure their application has the best chance of success.