Question to the Home Office:

To ask the Secretary of State for the Home Department, pursuant to the Answer of 8 January 2025 to Question 16332 on Undocumented Migrants, whether she plans to make an estimate of the number of people in the UK illegally.

By its very nature, it is not possible to know the exact size of the illegal migrant population, and so the Home Office under successive governments has not published any official estimates of the illegal migrant population. In June 2019, the Office for National Statistics (ONS) published a note on ‘Measuring illegal migration: our current view’.

Official statistics published by the Home Office are kept under review in line with the code of practice for statistics, taking into account a number of factors including user needs, the resources required to compile the statistics, as well as quality and availability of data.