Question to the Home Office:

To ask Her Majesty's Government how many individuals they estimate to be in the United Kingdom illegally.

Any estimate of the exact size of the illegal population is extremely difficult and there would be considerable uncertainty around it.

Exit checks were introduced in April 2015 and are, over time, providing more detailed insights into the behaviour of migrants and how they comply with the restrictions placed upon their length of stay in the UK, but the data obtained does not provide the total number of illegal migrants in the UK. Instead of producing inaccurate numbers, the Government is focused on making it harder for people to live in the UK illegally.

The International Passenger Survey is the responsibility of the Office for National Statistics and does not provide estimates of the size of the illegal population.