British citizenship by naturalisation and registration are the two statutory paths set out in the British Nationality Act 1981. Naturalisation is the standard route for adults who have built up residency in the UK and can meet a discretionary set of requirements: lawful residence, settled status, good character, and passes in the language and knowledge tests. Registration is a different animal — for many applicants it is a legal entitlement rather than a favour, and it exists mainly for children and for people who missed out on citizenship because of historical gaps in the law. Which one applies to you depends less on preference than on your age, your history, and your family background.
Who Qualifies for Naturalisation
Naturalisation is aimed at adults who have been living in the UK long enough to call it home. The core requirement is five years of lawful residence, with Indefinite Leave to Remain (ILR) or settled status held for at least the final twelve months. Across those five years, absences from the UK must not exceed 450 days in total, and no more than 90 days in the final year.1GOV.UK. Apply for Citizenship if You Have Indefinite Leave to Remain or Settled Status You must also have been physically present in the UK on the day exactly five years before the Home Office receives your application. Missing that date can sink the application outright, though the Home Office will consider genuinely exceptional circumstances such as illness or travel restrictions.
If you are married to or in a civil partnership with a British citizen, the residency requirement drops to three years, and you can apply as soon as you hold ILR or settled status rather than waiting an additional twelve months. The absence cap on this shorter route is 270 days over three years, with the same 90-day limit in the final year.2GOV.UK. Apply for Citizenship if Your Spouse Is a British Citizen
The Home Secretary has discretion to overlook minor breaches of the residency rules where the circumstances are genuinely exceptional. A short holiday that pushes you a few days over the limit is treated very differently from months of unexplained absence.
The Good Character Requirement
Every naturalisation applicant must satisfy the Home Office that they are of good character, which goes well beyond having no criminal record. Caseworkers examine police records, immigration history, and financial affairs. Any significant criminal conviction, immigration fraud, or deliberate deception in a previous application will normally result in refusal.
Financial conduct matters more than many applicants expect. Unpaid taxes, reckless accumulation of debt with no intention to repay, and NHS debts over £500 can all count against you. Bankruptcy alone is not an automatic bar — if it resulted from genuine misfortune rather than recklessness, and especially if the discharge happened more than ten years ago, the application can still succeed.3GOV.UK. Good Character Requirement Bankruptcy involving fraud, or a disqualification order barring you from company directorship, is a near-certain refusal. Ordinary consumer debt such as a mortgage, credit cards, or a car loan is not a problem as long as you are keeping to agreed repayments.
Council tax arrears sit in a grey area. Falling behind because of genuine hardship, particularly if you have arranged a repayment plan, will not normally sink an application. Deliberately avoiding council tax or lying about your circumstances will.3GOV.UK. Good Character Requirement
Language and Knowledge Tests
Applicants between 18 and 65 must pass the Life in the UK test, which costs £50 and must be booked at least three days in advance.4GOV.UK. Life in the UK Test You also need to prove your English at CEFR level B1 or above, usually through an approved Secure English Language Test.5GOV.UK. Prove Your Knowledge of English for Citizenship and Settling Holders of a degree taught in English and nationals of majority-English-speaking countries may already meet this requirement without sitting a separate test.
Who Qualifies for Registration
Registration works on a different logic. For many of the statutory routes, citizenship is an entitlement — meet the criteria and the Home Secretary must register you. There is far less discretion involved, and registration does not normally require the Life in the UK test or an English language qualification.
Children Born in the UK
A child born in the UK does not automatically become a British citizen unless at least one parent was a British citizen or settled in the UK at the time of birth. Where neither parent had that status at birth but a parent later obtains ILR or settled status, the child can be registered.6GOV.UK. Apply for Citizenship if You Were Born in the UK
A separate route covers children who have simply lived in the UK for their first ten years. Under section 1(4) of the British Nationality Act 1981, a child born in the UK is entitled to register once they turn ten, provided they were not absent for more than 90 days in any single year of those ten.7Legislation.gov.uk. British Nationality Act 1981 The word “entitled” matters: this is a right, not a favour. Where special circumstances explain extended absences, there may still be flexibility. Children aged ten or older must also meet the good character requirement.8GOV.UK. Registration as British Citizen: Children
Historical Routes and Windrush
Before 1983, British citizenship could only pass through the father. Children of British mothers born abroad before that date were left out. Later amendments allow those people to register, and similar barriers affecting children born to unmarried British fathers have been removed.
Section 4L of the Act, introduced by the Nationality and Borders Act 2022, creates a broad registration route for adults who would have been British citizens but for historical legislative unfairness, an error by a public authority, or truly exceptional personal circumstances. A person registered under this route becomes a British citizen otherwise than by descent, meaning they can pass citizenship on to children born outside the UK.9GOV.UK. Registration as a British Citizen in Special Circumstances
Members of the Windrush generation, Commonwealth citizens who settled in the UK before 1 January 1973, have a dedicated scheme. Applications under the Windrush Scheme are free, and those settled before that date are not required to pass the Life in the UK test or attend a citizenship ceremony unless they choose to.10GOV.UK. Windrush Scheme: Full Eligibility Details Their children may also qualify, depending on the parent’s immigration history.
People born in British Overseas Territories can qualify for registration under specific provisions of the Act. Once a child turns eighteen, most registration routes close, and they must pursue naturalisation instead unless they fit one of the historical categories.
Fees
Citizenship fees are substantial and non-refundable, even if the application is refused. From 8 April 2026 the schedule is:11GOV.UK. Home Office Immigration and Nationality Fees, 8 April 2026
- Adult naturalisation: £1,709 plus the mandatory £130 ceremony fee, totalling £1,839.
- Adult registration: £1,540 plus the £130 ceremony fee, totalling £1,670.
- Child registration: £1,000. If the child turns 18 during processing, a £130 ceremony fee is added before the decision is issued.
- Windrush Scheme: no fee.
- Nationality review (Form NR): £513, if you ask the Home Office to reconsider a refusal.
These figures do not cover the £50 Life in the UK test or the cost of an English language test, which varies by provider. Budget for the full amount before applying; the Home Office will not process a partially paid application.
How to Apply
The form for adult naturalisation is Form AN. For children under 18, it is Form MN1.12GOV.UK. Form MN1: Guidance Both require two referees who can confirm your identity and character. One must be a professional such as an accountant, solicitor, minister of religion, or civil servant, and can be of any nationality. The other must hold a British citizen passport and be either a professional or aged 25 or over.13GOV.UK. Form UKF Guidance – Section: Referees Neither referee can be your immigration representative or a relative.
You will need a full ten-year travel history with specific entry and exit dates. The Home Office cross-checks this against passport stamps and its own border records, so accuracy matters. Boarding passes, flight confirmations, and travel receipts help fill gaps in memory. Employment history and your National Insurance number confirm your financial and social ties to the UK.
Have your current and expired passports ready, along with your Biometric Residence Permit if you hold one, and any birth certificates. If you have already passed the Life in the UK test or hold an English language qualification, the unique reference numbers go on the form. All supporting evidence is uploaded digitally during final submission.
Applications go in through the GOV.UK portal. After paying the fee, you book an appointment at a UK Visa and Citizenship Application Services (UKVCAS) centre for biometrics — fingerprints and a digital photograph — and your documents are scanned there for a caseworker.14GOV.UK. UK Visa and Citizenship Application Services Decisions typically take up to six months. If a case will run longer, the Home Office should tell you before the six-month mark.15GOV.UK. Apply for Citizenship if You Have Indefinite Leave to Remain – After You’ve Applied
The Citizenship Ceremony
If your application succeeds, the Home Office sends an invitation to attend a citizenship ceremony at a local council office. You must book the ceremony within 14 days of receiving the invitation, and the ceremony must take place within three months.16GOV.UK. Citizenship Ceremonies Guidance Notes Missing that window creates real problems, so do not sit on the letter.
The ceremony is a legal requirement for adults. You swear or affirm an oath of allegiance to the monarch and pledge to respect the rights and freedoms of the United Kingdom. At the end, you receive your certificate of naturalisation or registration, which is the document you need to apply for a first British passport. Children are not required to attend.
If Your Application Is Refused
There is no statutory right of appeal against a refused naturalisation or registration application. This catches many people off guard, because appeals exist in other parts of immigration law. What you can do is request a reconsideration using Form NR, which costs £513.11GOV.UK. Home Office Immigration and Nationality Fees, 8 April 2026 The NR process asks the Home Office to look again at whether the decision was soundly based on law, policy, or procedure.17GOV.UK. Application for Review When British Citizenship Is Refused: Form NR
If reconsideration also fails, you can submit a fresh application with a new fee; the old application is not kept under review. Judicial review may be an option in some cases, particularly where the Home Office misapplied its own published policy or acted unreasonably. Getting the application right the first time is far cheaper than challenging a refusal.
Losing Citizenship After It Is Granted
British citizenship, once granted, is not necessarily permanent. Under section 40 of the British Nationality Act 1981, the Home Secretary can deprive someone of citizenship in two situations.18GOV.UK. Deprivation of British Citizenship: Caseworker Guidance
The first is where deprivation would be conducive to the public good, covering involvement in terrorism, espionage, serious organised crime, or war crimes. This ground cannot be used if it would leave the person stateless, unless their conduct was seriously prejudicial to the UK’s vital interests and they are able to acquire another nationality.
The second is where citizenship was obtained through fraud, false representation, or deliberate concealment of a material fact. For this ground, statelessness is not a barrier: the Home Secretary can revoke citizenship even if the person has no other nationality. The standard of proof is the balance of probabilities, not the criminal standard.
Unlike a refused application, a deprivation decision carries a right of appeal to the First-tier Tribunal under section 40A.19Legislation.gov.uk. British Nationality Act 1981 – Section 40A The order remains in effect while the appeal is pending. National security cases may be redirected to the Special Immigration Appeals Commission.
Dual Citizenship
The UK allows dual citizenship without restriction. Becoming a British citizen does not require you to give up your existing nationality, and acquiring a foreign citizenship later does not cost you your British status.20GOV.UK. Dual Citizenship The practical issue is what your other country allows. Many countries do not recognise dual nationality, and some will automatically revoke your original citizenship if you naturalise elsewhere. Check with the embassy or consulate of your home country before applying.