How many illegal immigrants coming to Britain are men?
Executive summary
Available official sources say it is not possible to produce a precise, up‑to‑date count of how many people living in the UK without permission are men, but population subsets that are measured show a strong male skew — most strikingly among “small boat” channel crossings, where the Home Office‑recorded data compiled in public sources shows roughly nine in ten arrivals are male [1][2].
1. The measurement problem: official bodies refuse to produce a single male/female breakdown for “illegal” residents
The Office for National Statistics and the Home Office decline to offer a definitive estimate of the size or sex composition of the unauthorised resident population, saying the number and characteristics of people in the UK without permission are largely unknown and that official sources do not identify illegal migrants separately [3][1]. Independent analysts and commentators repeatedly warn that methods for estimating the unauthorised population require large assumptions and yield wide, uncertain ranges rather than a precise male/female split [4][5].
2. What is known: small‑boat Channel crossings are overwhelmingly male
Where the government does collect sex and age breakdowns for specific entry routes, the data show a heavy male majority. Public compilations of Home Office figures for arrivals by small boats (2018–2024) record 147,568 arrivals with a breakdown of 129,615 men and 17,953 women, a proportion roughly nine men to every woman in that route [2]. That specific statistic is the clearest and best‑documented indicator in the public record that recent irregular arrivals via the Channel have been predominantly male [2].
3. But small boats are only one slice of a complex picture
Small‑boat arrivals, although prominent in political debate, are a fraction of overall migration and of the wider set of people who may be unauthorised — the Home Office and analysts caution against extrapolating Channel figures to the total undocumented population [6][1]. The unauthorised population also includes people who overstayed visas or who lost lawful status after arriving by formal routes; advocacy groups note that the “vast majority” of undocumented people first came through formal routes and later became undocumented for varied reasons, which may produce different gender balances than those seen at the Channel [7].
4. Historical and independent estimates give totals but not reliable sex breakdowns
Research groups and think‑tanks have produced wide numeric estimates of the UK’s unauthorised population — for example studies that historically ranged from a few hundred thousand up to around 1.2 million — but those estimates focus on counts and have been criticized for methodology, and do not provide a robust, current male/female percentage for the whole group [4][8][9]. The Migration Observatory and Full Fact stress that estimating either total size or characteristics such as sex requires assumptions that produce considerable uncertainty, and therefore claimants of precise totals or neat demographic splits are on weak empirical ground [5][10].
5. Political narratives and hidden agendas shape how the “how many are men” question is used
Channel‑crossing male majority figures are frequently amplified in political campaigns and media stories to justify policy shifts; opponents argue such amplification can obscure the diversity of undocumented people and the many pathways into undocumented status [2][7]. Meanwhile, circulation of headline totals (for example claims that 1.2 million people are “illegal”) has been debunked as reliant on flawed or out‑of‑date methods, underscoring that single big numbers or simple male/female claims are often weaponised in policy debates [9][8].
6. Bottom line: a precise national percentage is not available, but route‑level data show most recent small‑boat arrivals are men
There is no official, reliable figure that answers “what share of all illegal immigrants in Britain are men” because the Home Office/ONS do not produce a comprehensive, current demographic breakdown of the unauthorised resident population [3][1]. The best concrete statistic in the public record is route‑specific: documented small‑boat arrivals between 2018 and 2024 were overwhelmingly male (129,615 men versus 17,953 women) — about nine in ten — but that proportion should not be taken as representative of all undocumented people in the UK [2][6].