How to Get British Citizenship: Routes, Requirements, and Costs

To get British citizenship, most adults apply for naturalization after five years of lawful UK residence (three if married to a British citizen) plus at least 12 months holding Indefinite Leave to Remain or settled status, then pass the Life in the UK test, meet the English language and good character requirements, pay £1,735 in fees, and take the oath at a citizenship ceremony. Children and people with historical ties to the UK use a separate route called registration, and some people born abroad to a British parent are already citizens by descent without needing to apply.

Which Route Applies to You

Naturalization

This is the standard adult route. If you are not married to or in a civil partnership with a British citizen, you need five years of lawful residence in the UK followed by at least 12 months holding ILR or settled status before you can apply.¹ If you are married to or in a civil partnership with a British citizen, the qualifying period drops to three years, and you can apply as soon as you hold ILR or settled status with no additional 12-month wait.²

Registration

Registration applies mainly to children and people with historical ties to the UK. A child born in the UK who was not British at birth can be registered if, before the child turns 18, a parent becomes a British citizen or gains settled status.³ A child who has lived in the UK for the first 10 years of their life can also register.⁴ British Overseas Territories citizens may register after meeting UK residence requirements.⁵

Citizenship by Descent

If you were born outside the UK on or after 1 January 1983, you may already be a British citizen automatically if at least one parent was a British citizen “otherwise than by descent” at the time of your birth. That phrase means your parent’s citizenship came through being born in the UK, being naturalized, or being registered, not simply through having a British parent themselves.⁶ In limited circumstances citizenship can pass through a grandparent, but only where the parent was born abroad and the grandparent’s own citizenship meets specific criteria.

Residence and Absence Limits

Counting years is only half the residence test. The Home Office also counts your days out of the UK, and exceeding the limits is one of the most common reasons applications fail.

On the five-year route, you cannot have been absent for more than 450 days total during those five years, and no more than 90 days in the final 12 months before your application date.⁷ On the three-year spouse route, the limit is 270 days across three years, with the same 90-day cap in the final year.²

You must also have been physically present in the UK on the exact date that marks the start of your qualifying period, meaning five years (or three) before the date the Home Office receives your application. This catches people off guard more than almost any other requirement, because there is no way to fix it retroactively. If you were abroad on that date, your application will be refused. The Home Office can exercise discretion to overlook excess absences in some cases, but this is not something to rely on. Track your travel dates using your passport stamps and any other entry or exit records.

The Life in the UK Test

You must pass the Life in the UK test before applying. It contains 24 questions drawn from the official study handbook, and you need to answer at least 18 correctly, a pass mark of 75%.⁸ You get 45 minutes, which is generous for the number of questions. The fee is £50, booked through an approved test centre.⁹

If you fail, you can rebook as many times as you need, paying £50 each time.⁸ The questions cover British customs, history, and institutions. Most of the content is not common knowledge, so working through the official handbook matters even if you have lived in the UK for decades.

English Language Requirement

You need to prove English at B1 level on the Common European Framework of Reference, roughly intermediate: enough to hold a conversation and understand everyday written information. The standard proof is a Secure English Language Test (SELT) at an approved centre, which costs around £150. You are exempt if you are a national of a majority-English-speaking country, hold a degree taught or researched in English, or are under 18 or aged 65 and over.

Good Character

The Home Office assesses good character for everyone aged 10 and over who applies.¹⁰ This is broader than criminal history. Financial dealings, immigration compliance, and general conduct all count.

A custodial sentence of 12 months or more will normally result in refusal, and there is no fixed waiting period after which this clears. Consecutive shorter sentences that total 12 months or more have the same effect.¹⁰ Failing to disclose relevant information, even if the underlying issue might not have caused a refusal on its own, can be treated as dishonesty and lead to rejection. The good character assessment is the area where applicants are most tempted to omit inconvenient facts, and it is exactly the area where omissions do the most damage.

What It Costs

A naturalization application for an adult totals £1,735: £1,605 for the application plus a mandatory £130 citizenship ceremony fee.¹¹ Registering a child as a British citizen costs £1,214. Fees are not refundable if your application is refused.

On top of the application fee, expect to pay separately for:

Life in the UK test: £50 per attempt
English language test: around £150 if required
Biometric enrollment: approximately £19 at a UKVCAS service point

All in, a first-time applicant who passes the Life in the UK test on the first try spends roughly £1,950 or more.

Documents You Need

The application asks for detailed personal, employment, and travel history covering the entire qualifying period. The Home Office cross-checks the dates you give against your passport stamps, so accuracy matters.

Your current passport and every previous passport covering your time in the UK
Proof of settled status or ILR: your Biometric Residence Permit or digital share code
Proof of continuous residence: utility bills, bank statements, payslips, P60s, or tenancy agreements
Life in the UK test pass notification
English language test certificate, unless exempt

If your passport stamps do not clearly show your travel history, you will need additional evidence such as employer letters with dates, education records, or benefit statements to account for your presence in the UK.

Applying and Attending Biometrics

Applications are submitted online through the GOV.UK portal. After submitting, you book a biometrics appointment through UK Visa and Citizenship Application Services (UKVCAS), where your fingerprints and photograph are taken.¹² Bring a printed copy of your appointment confirmation with a QR code, your passport, and any supporting documents you have not already uploaded. If your application includes family members, you all attend together, and children under 16 must attend with a named responsible adult.

You will not receive a decision at the biometrics appointment. The Home Office targets a decision within six months of your application, though straightforward cases sometimes resolve in three to four months. Complex cases, particularly those involving good character concerns or excess absences, can take longer.

The Citizenship Ceremony

Approval is not the last step. The Home Office sends you an invitation to a citizenship ceremony, and you must attend within three months of receiving it.¹³ The ceremony is organized by your local council and is mandatory for everyone aged 18 and over.

You make an oath of allegiance (or an affirmation, if you prefer not to swear by God) and a pledge to respect the rights, freedoms, and laws of the United Kingdom. You then receive your certificate of British citizenship. You are not legally a British citizen until the ceremony is complete, so do not let the three-month deadline slip.¹³

If Your Application Is Refused

There is no formal right of appeal against a citizenship refusal. This differs from most other immigration decisions, and it surprises many applicants. What you can do is request a reconsideration by submitting Form NR to the Home Office, explaining why you believe the decision was wrong.¹⁴

Reconsideration is not a guaranteed second chance. If the refusal was based on excess absences or failing the good character assessment, resubmitting the same facts will produce the same result. Judicial review through the courts is theoretically available where you can show a clear legal error, but it is expensive and rarely successful without strong grounds. Getting the application right the first time matters far more for citizenship than for most other immigration applications, precisely because your options after a refusal are so limited.

Keeping Your Existing Citizenship

You can hold British citizenship alongside the citizenship of any other country. The UK places no restrictions on this, and you do not need to renounce your existing nationality when you apply.¹⁵ Check the rules in your home country before applying, though, because not every country is as relaxed. Some will automatically revoke your citizenship if you voluntarily acquire another nationality.

1
GOV.UK. Check if You Can Become a British Citizen
2
GOV.UK. Apply for Citizenship if Your Spouse Is a British Citizen
3
GOV.UK. Registration as British Citizen: Children (Accessible)
4
GOV.UK. Apply for Citizenship if You Were Born in the UK
5
GOV.UK. Guide B1: Registration as a British Citizen – A Guide for British Overseas Territories Citizens (Accessible)
6
GOV.UK. British Citizenship: Caseworker Guidance
7
GOV.UK. Naturalisation as a British Citizen by Discretion (Accessible)
8
GOV.UK. Life in the UK Test: What Happens at the Test
9
GOV.UK. Life in the UK Test
10
GOV.UK. Good Character Requirement (Accessible)
11
UK Parliament House of Commons Library. Cost of Naturalisation as a British Citizen, 1975-2025
12
GOV.UK. UK Visa and Citizenship Application Services
13
GOV.UK. Citizenship Ceremonies
14
UK Government Publishing Service. Form NR: Reconsideration of Decisions to Refuse British Citizenship
15
GOV.UK. Dual Citizenship