But as we explained in our fact check last week, this figure is not reliable, based on the details reported. The Conservative analysis reportedly compared 2025 prison data to 2021 population statistics which are likely out of date, and appears to have used data on the imprisonment of foreign nationals in general to draw conclusions about small boat arrivals specifically. While tens of thousands of people detected entering the UK irregularly arrive via small boat crossing, thousands are also detected via other routes (for example, in lorries). And, as the University of Oxford’s Migration Observatory has noted, it’s difficult to accurately estimate the number of people entering or living in the UK illegally, because many may never be detected. We’ve contacted Reform UK for comment.

Source: The Times July 15, 2025 16:48 UTC