Research Report: Irregular migration to the UK

This release provides an overview of irregular migrants who come to the UK. This includes those arriving on a small boat across the English Channel (a ‘small boat arrival’), a phenomenon that was rare prior to 2019 but has since increased notably in number, along with some other groups arriving without prior lawful permission.

The statistics presented here relate to the number of people recorded being detected on, or shortly after, arrival to the UK on various routes. They do not provide an indication of the total number of people currently in the UK who have entered the UK via irregular routes or the number of irregular migrants present in the UK. It is not possible to know the exact size of the irregular population currently resident in the UK, nor the total number of people who enter the UK irregularly.

A small boat is only one of a number of irregular methods by which a person may reach the UK border and seek entry without permission. This release provides additional statistics on other irregular modes of entry but not all irregular entries will be recorded and we are not able to provide an estimate for the entirety of the irregular migrant population. Some people may enter the UK on regular routes and their status subsequently become irregular (for example if they overstay their visa). Others may enter through an irregular method and remain undetected or will be detected some time after their arrival. Additionally, other migrants may enter irregularly but gain ‘regular’ status (for example following an application for asylum).