To apply for British citizenship by naturalisation, you must meet the UK citizenship residency requirement. This means showing that you have lived legally in the UK for a set period, kept within travel limits, and hold settled or indefinite leave to remain status.
What are the residency requirements for UK citizenship?
The residency requirement for naturalisation—also called the UK citizenship residency requirement—is the set of rules that show you have lived lawfully in the UK long enough to apply for British citizenship. Here is everything you need to know:
How long do you need to live in the UK to become a citizen?
There are two main residency periods, depending on your situation:
Applicant type | Minimum UK residence |
Not married to a British citizen | 5 years before the date you apply |
Married to a British citizen | 3 years before the date you apply |
You must also have been physically present in the UK exactly 5 or 3 years before your application date. If you were abroad that day, your application could be refused.
Settled or Indefinite Status
Before applying, you must have Indefinite Leave to Remain (ILR) or settled status.
If you’re applying after 5 years, you must have held ILR or settled status for at least 12 months.
If you’re applying as a spouse of a British citizen, you can apply as soon as you get ILR or settled status — no extra 12 months required.
How many days can you stay outside the UK for British citizenship?
Your absences from the UK must stay within Home Office limits:
Application type | Total time abroad allowed | In the final year |
5-year route | Up to 450 days in total | No more than 90 days |
3-year route (spouse) | Up to 270 days in total | No more than 90 days |
If you exceed these limits slightly, the Home Office may still accept your application, but only if there are strong reasons — for example, work for a UK company or unavoidable family circumstances.
What is the 90 day rule for naturalization?
The 90-day rule for naturalisation means you can only spend up to 90 days outside the UK in the 12 months before applying for British citizenship.
Lawful residence
You must have lived in the UK legally during the qualifying period. That means holding the right visa or status at all times and no immigration breaches or overstaying.
On the day you apply, you must be free from immigration time limits — in other words, you already have ILR or settled status.
Intention to stay in the UK
You must plan to live in the UK permanently after becoming a British citizen. If you live abroad, you should show strong ties to the UK, for example, a UK employer or home.
What is the fastest way to get UK citizenship?
The fastest way to get UK citizenship is by being married to or in a civil partnership with a British citizen. In this route, you can apply after 3 years of living in the UK, instead of the usual 5.
To qualify, you must:
Hold Indefinite Leave to Remain (ILR) or settled status.
Have lived in the UK for 3 years before applying.
Spend no more than 270 days abroad in those 3 years and no more than 90 days in the last year.
Pass the Life in the UK Test and meet the English language requirement.
If you’re not married to a British citizen, you can apply after 5 years of residence and 12 months with ILR or settled status.
In short, marriage to a British citizen offers the quickest route, while the standard naturalisation process usually takes about 6 years in total (5 years of residence + 1 year settled).
