Question to the Home Office:

To ask Her Majesty’s Government what assessment they have made of the proportion of illegal migrants living in the United Kingdom who entered the United Kingdom on a visa.

There are no government estimates on the number of illegal migrants currently living in the UK who entered the country on a visa. Any such estimation would be extremely difficult and there would be considerable uncertainty around it. Instead of producing such uncertain estimates, Her Majesty's Government is focusing on making it harder for people to live in the UK illegally and has introduced exit checks, which over time, will improve the ability to identify individuals who have overstayed.