On this page
In brief
- Naturalisation is the discretionary process by which an adult may acquire British citizenship under section 6 of the British Nationality Act 1981.
- The main split is standard (section 6(1)) versus the British-citizen spouse route (section 6(2)).
- Both review residence, presence and immigration status, plus good character, language and Life in the UK.
- The guide helps identify which framework applies.
What is naturalisation?
Naturalisation is a discretionary route to British citizenship for adults. The Home Secretary may grant a certificate of naturalisation where the statutory framework is engaged, but naturalisation is not an automatic entitlement simply because the statutory matters have been addressed (Naturalisation guidance, “Requirements to naturalise as a British citizen”).
Before treating naturalisation as the appropriate citizenship route, it may also be necessary to consider whether a person is already a British citizen, or may instead have a registration entitlement. The guidance directs caseworkers to make those checks — though the separate registration guidance is not part of this source set, so this page does not determine whether someone is already British or entitled to registration.
Which naturalisation framework applies?
The Home Office guidance separates adult naturalisation into two principal statutory frameworks. A person who is not applying on the basis of marriage or civil partnership with a British citizen is considered under section 6(1). A person who is married to or in a civil partnership with a British citizen is considered under section 6(2) (Naturalisation guidance, “Requirements to naturalise as a British citizen”). The residence and structural frameworks are not identical.
General naturalisation
The framework for applicants not applying within the British-citizen spouse or civil-partner provisions — covering adulthood and capacity, the applicable residence framework (or certain Crown-service circumstances), good character, language, knowledge of life in the UK and future intentions.
British citizen spouse / civil partner
The framework where the person is married to, or in a civil partnership with, a British citizen — covering adulthood and capacity, the British-citizen relationship basis, residence, good character, language and knowledge of life in the UK. The route-specific residence framework differs from section 6(1).
These pages explain the respective frameworks without determining an individual’s eligibility.
Standard naturalisation, or the British-citizen spouse route?
Most adults naturalise under section 6(1). A person married to, or in a civil partnership with, a British citizen may instead use section 6(2). The routes overlap but differ on residence and future intentions. This is a general comparison, not a decision on your case.
| Feature | Section 6(1) — standard | Section 6(2) — spouse / civil partner of a British citizen |
|---|---|---|
| Who it is generally for | Most adults who are settled in the UK | An adult married to, or in a civil partnership with, a British citizen |
| Settled status / ILR (or equivalent) | Generally required | Generally required |
| Qualifying residence period | The standard qualifying period | Generally a shorter qualifying period |
| Further period holding settled status before applying | Usually applies | Generally not required in the same way |
| Future-intentions requirement | Applies | Does not apply in the same way |
| Good character | Applies | Applies |
| English language & Life in the UK | Apply, unless an exemption applies | Apply, unless an exemption applies |
Citizenship applications remain subject to the statutory requirements and, where applicable, Home Office discretion — meeting the general position above does not guarantee a grant. Review the detailed frameworks: section 6(1) and section 6(2) (British-citizen spouse), and the good character guide.
Residence, presence and immigration status
Residence and presence. Residence is part of both principal naturalisation frameworks. The guidance distinguishes the section 6(1) and section 6(2) residence structures and includes issues concerning presence at the beginning of the relevant residence period, absences, technical absences and immigration-law status. This overview does not reproduce numerical residence periods or absence limits — the applicable framework should be reviewed on the relevant route page and against current official guidance. For the shared concept, see continuous residence.
Immigration status and history. Naturalisation includes consideration of immigration status — a specific framework concerning freedom from immigration time restrictions, and separately, breaches of immigration law during the relevant residence period. A straightforward application may involve reviewing current status and residence evidence. But where there is a disputed immigration history, unlawful residence, detention, immigration bail, an alleged breach or reliance on discretion, the matter falls outside this straightforward page. Refusal or complex issue → immigration help.
Good character, language, knowledge of life and capacity
Good character forms part of both principal frameworks. The detailed framework is owned by our Knowledge page — see good character for British citizenship. This page identifies good character only as a separate framework requiring review; where a case involves a potentially contentious good-character issue, it should be treated as a complex matter rather than assessed through a guide-only page.
English language and Knowledge of Language and Life both feature within the section 6(1) and section 6(2) structures, but the detailed rules, levels and evidence are owned by their Knowledge pages and are not duplicated here — see the English language requirement and Knowledge of Language and Life, and confirm current requirements against the relevant GOV.UK material.
Capacity. The guidance includes a full-capacity requirement — concerning an applicant’s understanding of the decision to acquire British citizenship — with provision for waiver in particular circumstances. Routine cases may simply identify capacity as an area to review; where capacity is in question or a waiver may be needed, the case may require specialist consideration outside a straightforward Level 1 service.
Future intentions, specialist service and children
Future intentions form part of the section 6(1) framework — whether the applicant intends to maintain the relevant connection with the UK, including through the principal-home framework or certain qualifying service or employment. This is route-specific and is covered in more detail on the section 6(1) guide.
Specialist Crown and armed-forces cases. The guidance contains separate frameworks for applications connected with Crown service, the armed forces and related categories — Crown-service cases can involve a distinct discretionary basis rather than the ordinary residence framework, and the armed-forces provisions include special treatment of absences and internal referral mechanisms. These are not presented here as routine naturalisation applications. Refusal or complex issue → immigration help.
Children and British citizenship. Children are not naturalised through the adult naturalisation framework. Where a child is involved, consideration may instead concern whether the child is already British or may be registered as a British citizen — the separate child-registration guidance has not been supplied, so this page does not provide a child-registration assessment.
What happens after naturalisation?
A certificate of naturalisation is legal evidence of acquisition of British citizenship and should be carefully preserved. Post-naturalisation matters also touch on British passports, right of abode and dual nationality. For source-controlled post-naturalisation information, see after naturalisation →.
Issues and evidence areas to review
- Which statutory framework applies: section 6(1) or section 6(2)
- Adult naturalisation rather than another British citizenship route
- Full-capacity framework
- Route-specific residence framework; presence and absence history
- Immigration-status framework; lawful-residence issues
- Good-character framework
- English-language framework
- Knowledge of Language and Life framework
- Future intentions where relevant to section 6(1)
- Whether a specialist Crown or armed-forces framework is involved
Not an exhaustive required-documents list. Areas may include:
- Identity and nationality evidence
- Evidence relating to immigration status
- Residence and travel-history material
- Evidence relevant to the applicable statutory route
- Marriage or civil-partnership evidence where section 6(2) applies
- Language and Knowledge of Language and Life evidence
- Material relevant to good-character review
- Evidence relating to future intentions where relevant
- Capacity-related evidence where the issue arises
This is an issue-identification and evidence-area list only; it does not determine whether any requirement is satisfied. Current application and documentary requirements should be confirmed against the applicable official source before submission.
Thinking about British citizenship? Get an honest, fixed-fee view of your naturalisation options.
Get a fixed-fee quoteOur regulatory scope. ENS Immigration Advice is regulated by the Immigration Advice Authority at Level 1 and can assist with straightforward naturalisation applications within its authorised competence. Existing refusals, disputed immigration histories, alleged breaches, complex good-character matters, capacity or waiver questions, and specialist Crown or armed-forces cases fall outside that pathway — we will identify the relevant framework and direct you to the appropriate next step. Refusal or complex issue → specialist referral.
How ENS can help
Identify the statutory framework
We can help identify whether section 6(1) or section 6(2) applies and which issues arise.
Review issues and evidence
We can help review the issues and evidence areas arising from a straightforward application.
Prepare a straightforward application
Where the matter is within our IAA Level 1 authorisation, we can assist with preparing and checking the application.
Frequently asked questions
What is naturalisation as a British citizen?
Naturalisation is a discretionary process through which an adult may acquire British citizenship under section 6 of the British Nationality Act 1981. The Home Office guidance separates the principal framework into section 6(1) and section 6(2) applications.
Who is the naturalisation route for?
The supplied guidance concerns adult naturalisation. Which framework needs review depends in part on whether the applicant is married to, or in a civil partnership with, a British citizen. The page does not determine whether naturalisation is the correct citizenship route for a particular person.
What is the difference between section 6(1) and section 6(2)?
Section 6(1) is the principal framework for applicants not applying within the British-citizen spouse or civil-partner provisions. Section 6(2) applies where the person is married to or in a civil partnership with a British citizen. The residence and structural frameworks are not identical.
Does this page tell me whether I qualify for British citizenship?
No. This page identifies the naturalisation framework, issues and evidence areas that may need review. It does not determine eligibility or predict a Home Office decision.
Does this page give the residence periods or absence limits?
No. Numerical residence periods, absence limits and other date-sensitive rules are not reproduced here. The applicable residence framework should be reviewed on the relevant naturalisation page and checked against current GOV.UK guidance.
Where can I read about the English-language requirement?
The detailed English-language framework is owned by the ENS Knowledge page at English language requirement. The naturalisation guidance confirms that language forms part of the relevant statutory framework, but the complete external language rules are not contained in the supplied source set.
Where can I read about Knowledge of Language and Life?
See Knowledge of Language and Life. The naturalisation guidance identifies knowledge of life in the UK within both principal frameworks, but this route page does not duplicate the detailed requirements.
What if I have previously been refused British citizenship or have a complex immigration history?
A refusal, disputed immigration history, alleged immigration breach or other contentious issue falls outside this straightforward guide and should be directed to complex immigration help.
Can children apply for naturalisation?
The supplied guidance states that children are not naturalised under the adult naturalisation framework. Their position may instead involve an existing British citizenship claim or registration as a British citizen. The separate child-registration guidance has not been supplied for this page.
How can ENS Immigration Advice help?
ENS Immigration Advice can help review a straightforward naturalisation application by identifying the relevant statutory framework, issues to review and evidence areas arising from the application. Where a refusal, disputed history or other complex issue is involved, the matter is directed to complex immigration help.
Source basis. Built from Nationality policy: Naturalisation as a British citizen by discretion, version 16.0 (published for Home Office staff 11 November 2025), and the Home Office information leaflet Care of Certificates of Registration and Naturalisation (no version or valid-from date is printed in the supplied document). Immigration and nationality rules, policy and operational guidance can change; confirm current requirements against the relevant GOV.UK material before an application is made.