What is Naturalisation in the UK

Naturalisation is the formal legal process through which a foreign national becomes a British citizen. It is granted under the British Nationality Act 1981 and represents the final stage for those who have lived lawfully in the UK and wish to make it their permanent home. By naturalising, a person obtains full citizenship rights, including the right to a British passport, the right to vote, and freedom from UK immigration control.

What this article is about: This guide explains what naturalisation means in UK law, who is eligible to apply, how the application process works, and the rights and obligations that follow citizenship approval.

Section A – Legal Definition and Purpose of Naturalisation

Naturalisation is the statutory process by which a person who is not already a British citizen may be granted British citizenship on application to the Secretary of State. It is governed principally by the British Nationality Act 1981 (the “1981 Act”), especially section 6 and Schedule 1. The grant is discretionary: satisfying the criteria does not confer an automatic right to citizenship, and the Home Office may refuse where it considers refusal appropriate in the public interest.

Statutory basis under the British Nationality Act 1981

Part I of the 1981 Act establishes British citizenship and the acquisition routes. Section 6(1) (standard route) and section 6(2) (spouse or civil partner of a British citizen) empower the Secretary of State to grant naturalisation if the applicant meets the conditions in Schedule 1 relating to residence, knowledge of language and life in the UK, good character and intention to continue living in the UK (or to enter or remain in Crown service). The evidential framework and decision-making approach are further set out in Home Office nationality policy guidance.

Discretion, not entitlement

Naturalisation is a matter of discretion. Even where the statutory requirements are met, the Secretary of State may refuse to grant citizenship, for example because of adverse conduct, public policy considerations or unresolved doubts about identity, residence or good character. Conversely, limited discretion may be exercised to overlook minor technical shortfalls (such as small excess absences) where policy allows and the applicant otherwise demonstrates strong ties and integration.

Naturalisation vs registration

Naturalisation is distinct from registration. Registration applies to people with an existing entitlement or claim to British nationality created by statute (for example certain children born abroad to British parents, or persons with historical or transitional rights). Naturalisation, by contrast, is the main route for long-term lawful residents—typically those holding Indefinite Leave to Remain (ILR) or Settled Status—who do not already possess such an entitlement.

Purpose and effect

The purpose of naturalisation is to recognise, in law, a settled and lasting connection to the United Kingdom. Upon grant, the individual acquires the full rights and responsibilities of British citizenship, including political rights (such as voting), eligibility for a British passport, and freedom from UK immigration control. Naturalisation also secures diplomatic protection abroad and removes the precarity associated with time-limited immigration leave.

Who typically applies

Typical applicants include: long-term residents with ILR obtained through work, family or protection routes; EU, EEA and Swiss nationals with Settled Status under the EU Settlement Scheme; and spouses or civil partners of British citizens who meet the shorter residence route. All applicants must still satisfy the statutory criteria and the Home Office’s character and suitability assessments.

Section A summary: Naturalisation is the discretionary grant of British citizenship under section 6 of the 1981 Act, intended to formalise the status of those with a settled connection to the UK. It differs from registration and takes effect only when the Secretary of State is satisfied, on the evidence, that the statutory conditions and public interest are met.

Section B – Eligibility Criteria for Naturalisation

The eligibility requirements for British citizenship by naturalisation are set out in Schedule 1 to the British Nationality Act 1981. They ensure that applicants demonstrate lawful residence, good character, knowledge of language and life in the UK, and a continuing intention to live in the country. Meeting these criteria establishes suitability for citizenship but does not create an automatic entitlement — each case remains subject to the Home Office’s discretion.

Residence requirement

The standard qualifying period is five years before the date of application. The applicant must have been physically present in the UK at the start of that period and must not have exceeded 450 days of absence in total, nor more than 90 days in the final year. Those married to or in a civil partnership with a British citizen may apply after three years of residence, with slightly modified absence rules.

The applicant must have held Indefinite Leave to Remain (ILR) or Settled Status for at least 12 months immediately before applying, unless applying as the spouse or civil partner of a British citizen, in which case this 12-month requirement does not apply.

Good character

All applicants aged 10 or over must satisfy the good character requirement. This involves consideration of criminal convictions, financial soundness, honesty in dealings with public bodies, and compliance with immigration law. The Home Office examines conduct over the previous decade and may refuse applications involving criminality, deception, or breaches of UK immigration control. Spent convictions and minor infractions are assessed in context under policy guidance.

Knowledge of language and life in the UK

Applicants aged 18 to 65 must demonstrate knowledge of language and life in the UK (“KoLL”). This requires passing the Life in the UK Test and meeting the English language requirement, typically by holding an approved English test certificate at level B1 CEFR or higher, or a degree taught in English. Nationals of majority English-speaking countries and those with long-term medical exemptions may be excused under regulation.

Lawful status and immigration compliance

The entire residence period must have been lawful. Applicants must not have overstayed any visa, breached conditions of leave, or been subject to immigration enforcement action. Gaps or irregularities in status can lead to refusal even if later rectified. The Home Office requires documentary proof of lawful residence, including passport entries, visas, and confirmation of ILR or Settled Status.

Intention to remain in the UK

Under paragraph 1(1)(f) of Schedule 1, the applicant must intend to continue living in the UK, or to enter or remain in Crown service, or serve an international organisation or a UK-linked company. Evidence of continued residence plans—such as employment, family ties, or property—supports this declaration.

Special cases and discretion

The Home Office may exercise discretion to waive minor excess absences or certain technical failures where strong evidence of integration and residence exists. Such concessions are not guaranteed and depend on individual circumstances. Applicants should document exceptional reasons, such as employment abroad with a UK company or family emergencies, to support requests for discretion.

Section B summary: To qualify for naturalisation, an applicant must satisfy residence, good character, language and lawful status criteria. The requirements reflect both the statutory conditions of the British Nationality Act 1981 and the Home Office’s expectation of long-term commitment to life in the UK.

Section C – Application Process for Naturalisation

The application for British citizenship by naturalisation is made to the Home Office using Form AN. The process is primarily online and supported by documentary evidence confirming eligibility under the British Nationality Act 1981. Each application is assessed individually to ensure compliance with residence, character, and knowledge requirements.

Completing the application

Applicants must complete the online Form AN accurately and honestly, providing full details of residence, employment, and absences over the qualifying period. Errors or omissions can delay a decision or result in refusal on character grounds. It is advisable to review all responses carefully and ensure consistency with immigration records.

Supporting documentation

Evidence must accompany the application to demonstrate compliance with statutory requirements. This typically includes:

• Current and previous passports covering the qualifying period;
• Proof of Indefinite Leave to Remain (ILR) or Settled Status;
• Evidence of lawful residence, such as visa stamps, Home Office letters, or travel records;
• English language qualification and Life in the UK Test pass notification;
• Two referees’ declarations meeting Home Office criteria, one of whom must be a British citizen and a professional person.

Fees and biometric enrolment

As at 2025, the Home Office fee for a naturalisation application is £1,630 per person. The fee covers processing and the citizenship ceremony cost. Applicants must also attend a biometric enrolment appointment to provide fingerprints and photographs at a designated UKVCAS service centre. Failure to attend may invalidate the application.

Processing and decision timeframe

Most applications are decided within 3 to 6 months of biometric submission. However, timeframes may vary depending on case complexity, volume of applications, and background checks. The Home Office conducts verification of residence, criminal records, and immigration history through internal and external databases. Applicants should avoid unnecessary travel or changes of address during this period to prevent communication delays.

Approval, refusal and reconsideration

If approved, the applicant receives an invitation to attend a citizenship ceremony within 90 days. At the ceremony, the individual takes an Oath or Affirmation of Allegiance and a Pledge of Loyalty to the United Kingdom. They then receive the Certificate of Naturalisation, which confirms British citizenship from that date.

If refused, the applicant receives written reasons for the decision. There is no right of appeal to an immigration tribunal, but a request for reconsideration may be made if the decision appears to contain an error or new evidence becomes available.

Practical considerations

Applicants are advised to keep copies of all submitted materials and correspondence. Legal representatives can be appointed but are not mandatory. Using up-to-date Home Office guidance and ensuring accuracy at every stage helps avoid delays or refusals based on administrative grounds.

Section C summary: Naturalisation is applied for using Form AN, supported by comprehensive documentation and payment of the Home Office fee. Biometric enrolment, background checks, and a citizenship ceremony complete the process leading to full British citizenship.

Section D – Rights and Responsibilities After Naturalisation

Once British citizenship is granted through naturalisation, the individual becomes a full citizen of the United Kingdom with the same legal rights and responsibilities as those who acquired citizenship by birth. The change is permanent and legally recognised from the date shown on the Certificate of Naturalisation.

Ceremony and confirmation of citizenship

The grant of citizenship takes legal effect only after attending a citizenship ceremony. During the ceremony, new citizens make an Oath or Affirmation of Allegiance to the Crown and a Pledge of Loyalty to the United Kingdom. This requirement reflects both the legal and civic significance of becoming a British citizen. The individual then receives the Certificate of Naturalisation, which should be stored securely as it is the primary proof of citizenship for passport and legal purposes.

Rights of British citizens

Naturalised citizens gain the full range of rights enjoyed by British nationals, including:

• The right to live and work in the UK without immigration restrictions;
• The right to vote in all UK elections and stand for public office;
• Access to public services and benefits on the same basis as other citizens;
• Eligibility for a British passport issued by His Majesty’s Passport Office;
• Consular assistance and diplomatic protection from UK embassies abroad.

Responsibilities and conduct

British citizenship also carries responsibilities. Citizens are expected to uphold UK laws, pay taxes, and participate in civic life. The good character standard continues to apply post-naturalisation, meaning serious criminal conduct can lead to deprivation of citizenship under section 40 of the British Nationality Act 1981 if obtained by fraud or concealment.

Dual citizenship and renunciation

The United Kingdom permits dual nationality. Naturalised citizens may retain their original citizenship unless their country of origin requires renunciation. Before applying for naturalisation, individuals should check whether holding two nationalities is legally allowed in their home country to avoid unintended loss of rights abroad.

Impact on family members

Naturalisation affects only the individual applicant. Family members, including spouses and children, do not automatically acquire British citizenship and must apply separately. However, once a parent becomes British, a child born in the UK thereafter usually becomes British automatically. Existing non-British children may register as citizens if they meet the relevant statutory conditions.

Section D summary: Naturalisation confers the full legal status, rights and civic duties of British citizenship. It marks both the completion of lawful residence and the beginning of a permanent and equal relationship with the United Kingdom.

FAQs

How long does the naturalisation process take?

Most naturalisation applications are processed within three to six months after biometric enrolment. However, complex cases or those requiring additional checks may take longer. The Home Office advises applicants not to make international travel plans during the decision period if original documents are held.

Can I apply for naturalisation if I have Indefinite Leave to Remain?

Yes. Indefinite Leave to Remain (ILR) or Settled Status is a key requirement for naturalisation. Applicants must normally hold ILR or Settled Status for at least 12 months before applying unless married to a British citizen, in which case the 12-month rule does not apply.

What happens if my naturalisation application is refused?

If refused, the Home Office issues a written explanation. There is no formal appeal right to a tribunal. However, applicants may request a reconsideration if they believe the refusal was made in error or if new evidence has come to light. A fresh application can also be made once any underlying issues are resolved.

Do I have to renounce my original nationality?

The United Kingdom allows dual nationality, so you may keep your original citizenship unless your home country’s laws prohibit it. Applicants should confirm their own country’s nationality rules before applying to ensure that naturalisation will not lead to an automatic loss of existing citizenship.

Does naturalisation automatically make my children British?

No. Citizenship is not automatically extended to family members. Children born in the UK after a parent becomes a British citizen are automatically British. Those born before that date or outside the UK may need to apply for registration as British citizens if eligible.

FAQs summary: The naturalisation process typically takes several months, requires ILR or Settled Status, and may involve reconsideration if refused. The UK permits dual nationality, but citizenship for family members depends on their individual circumstances.

Conclusion

Naturalisation is the formal legal route by which long-term residents secure full British citizenship. Governed by the British Nationality Act 1981, it is a discretionary process requiring applicants to prove lawful residence, good character, language proficiency, and integration into UK life. Unlike Indefinite Leave to Remain or Settled Status, naturalisation removes all immigration restrictions and grants the rights and protections of citizenship in full.

The process culminates in a citizenship ceremony, symbolising both legal completion and civic belonging. For many, it represents the final step in a journey of settlement, giving them the same standing as any other British citizen in law and society.

Conclusion summary: Naturalisation transforms permanent residents into full British citizens, providing legal security, civic identity, and the rights and duties that define membership of the United Kingdom.

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