ILR, or indefinite leave to remain, is permanent UK immigration status that lets a person live, work and study in the United Kingdom without a time limit. It removes visa conditions and is usually a step before British citizenship.
In one line: ILR is settled immigration status that lets someone stay in the UK permanently with no visa expiry date.
How ILR works
ILR is granted by the Home Office once a person has spent a qualifying continuous period in the UK on an eligible route, commonly five years, and meets residence, knowledge and conduct requirements.
Most adults applying for ILR pass the Life in the UK test and prove English language ability, then complete the relevant SET form. As an example, a Skilled Worker who arrived in June 2021 on a five-year route could become eligible to apply for ILR in 2026 once continuous-residence and absence limits are met.
Holding ILR ends the need to pay the immigration health surcharge and removes work restrictions, though the status can lapse after a long absence from the UK, typically two years outside the country (Home Office, 2026).
ILR vs naturalisation
ILR is an immigration status, not nationality. The person remains a citizen of their home country and keeps their existing passport, but gains the right to remain in the UK without limit.
Naturalisation is the later step of becoming a British citizen, which usually requires holding ILR or settled status for at least twelve months first, so ILR is generally a gateway rather than the final stage.
Primary source: Home Office: Indefinite leave to remain (GOV.UK)