British Citizenship After ILR: The 2026 Naturalisation Guide

Researched and maintained by the ILR Calculator UK editorial team · Reviewed against the British Nationality Act 1981 and Home Office nationality guidance in force on 24 June 2026 · General information about UK citizenship, not regulated immigration advice. For advice on your own case, use an adviser regulated by the Immigration Advice Authority (IAA) or a solicitor.

Once you hold Indefinite Leave to Remain, naturalising as a British citizen is usually the final step. Most people apply 12 months after getting ILR — or straight away if married to a British citizen — provided they meet the residence and absence limits, the good character requirement, English at B1 and the Life in the UK test. The adult fee in 2026 is £1,839, and you become a citizen only after a citizenship ceremony.

Why naturalise after ILR

ILR already lets you live and work in the UK without time limit, so why go further? Because citizenship is more secure and gives you more. ILR can be lost — it lapses if you spend more than two years continuously outside the UK, and can be revoked on serious criminality. Citizenship cannot lapse through absence, gives you a British passport and the right to vote, ends visa and settlement fees for good, and lets you pass citizenship to children. For most settled residents it is the point at which their status becomes truly permanent. Confirm your settlement date first with the ILR eligibility calculator, then plan citizenship with the naturalisation calculator.

Who can apply — the two routes

Naturalisation under the British Nationality Act 1981 comes in two forms, depending on whether your partner is British.

Source: British Nationality Act 1981, sections 6(1) and 6(2); GOV.UK nationality guidance. The 3-year route requires you to be married to, or in a civil partnership with, a British citizen at the date of application.

The requirements in full

Whichever route applies, you must meet all of the following:

• Aged 18 or over and hold ILR or settled status.
• Residence — 5 years in the UK (or 3 on the spouse route), and you must have been physically present in the UK on the day exactly 5 (or 3) years before the Home Office receives your application.
• Absences — within the limits below.
• English at B1 — rising to B2 for applications on or after 26 March 2027; most people have already met this at ILR. Check with our English requirement checker.
• Life in the UK test — the same pass used for ILR is accepted; it never expires.
• Good character — see below.
• Intention to keep living in the UK — the future-intentions requirement.

The absence limits

Absences are counted back from your application date, and getting them wrong is a leading cause of refusal.

Source: GOV.UK nationality guidance; Schedule 1, British Nationality Act 1981. Departure and arrival days count as days in the UK. Exceeding the limits leads to refusal unless the Home Office exercises discretion, which is granted only in exceptional cases.

The good character requirement

Good character is the most subjective part of the assessment, and the area where the rules have tightened in 2026. The Home Office does not just look for a clean criminal record — it weighs your overall conduct. Issues that can lead to refusal include:

• Criminality — convictions, cautions and, in some cases, ongoing proceedings.
• Immigration breaches — overstaying, working in breach of conditions, and illegal entry, which the Home Office now treats more strictly.
• Financial conduct — tax evasion, deliberate non-payment, and in some cases significant unpaid debt.
• Dishonesty — deception or non-disclosure in any immigration or nationality application.

You must declare everything, including spent convictions under the Rehabilitation of Offenders Act — non-disclosure is itself a ground for refusal. If you have anything in your history that might raise a concern, it is worth addressing it up front with evidence, or taking advice before you apply. For the thresholds, the illegal-entry rule and how to disclose issues, read our full guide to the good character requirement.

How to apply, step by step

The application is made online on Form AN. In practice it runs like this:

1. Confirm you have held ILR long enough — at least 12 months, unless you are married to a British citizen, in which case no wait applies.
2. Check your absences — within 450 days over 5 years (or 270 over 3 years) and no more than 90 days in the final 12 months.
3. Gather your documents and two referees — passports, ILR proof, Life in the UK and English evidence, and two qualifying referees.
4. Complete and submit Form AN online — and pay the £1,839 fee, which includes the ceremony charge.
5. Enrol your biometrics — provide your fingerprints and photograph at an appointment.
6. Attend your citizenship ceremony — once approved, take the oath and pledge and receive your certificate. You become a citizen only at the ceremony.

Fees and costs

Source: GOV.UK nationality fees, applications on or after 8 April 2026. The application fee is not refunded if refused, though the £130 ceremony element is. Citizenship is a separate, significant cost on top of your ILR fee of £3,226.

Dual nationality

The UK allows dual and multiple nationality, so you do not have to renounce your existing citizenship to become British. But some countries — including China, India and Japan — do not recognise dual nationality and may withdraw your original citizenship automatically when you naturalise. Always check your home country’s rules, and any tax implications, before you apply.

When you can apply

On the standard route, the clock is: five years’ residence to reach ILR, then hold ILR for 12 months, then apply — so citizenship typically comes around six years after you settled into a qualifying route. On the spouse route, once you have ILR and three years’ residence married to a British citizen, you can apply straight away. Work out your exact earliest date with the naturalisation calculator.