The correct terminology for full or permanent residency in the UK is Indefinite
Leave to Remain (ILR). You can apply for ILR following 5 continuous
years on the one type of visa such as Ancestry, Tier 1 or Tier 2. You can also qualify
for ILR following 2 years on a settlement visa such as married/unmarried partner
of British citizens or permanent residents. ILR allows you to remain in the UK for
an indefinite period, on condition you intend to remain present and settled there.
If you leave the country for a continuous period of 2 years or more, it is usually
deemed by the authorities that you are no longer present and settled, and you may
have your ILR revoked. ILR can only be applied for whilst you are present in the
UK and you must remain in the UK while the application is under consideration.
Read more on Indefinite Leave To Remain on the Visa Website
