A confidential report has revealed that an estimated 585,000 illegal migrants are residing in London—equating to one in every 12 residents. This startling figure, which has now emerged following a Freedom of Information request, sheds light on the scale of illegal migration in the UK capital. The report, commissioned by Thames Water and obtained by The Daily Telegraph, highlights that the majority of these individuals entered the UK legally on visitor or work visas but have overstayed their permitted duration.
The document has reignited concerns over the UK’s border controls, with some sources estimating that the total number of illegal migrants in the country exceeds one million, with 60% of them living in London. This has led to growing criticism of the government’s immigration policies and is intensifying calls for urgent action.
Public services across the capital, including the National Health Service (NHS) and schools, are feeling the strain. Local authorities are grappling with mounting pressures, while the so-called “black economy,” where many undocumented migrants find work in sectors like food delivery, is also being scrutinized. Critics argue that this undermines tax revenues and fair labour practices, placing an undue burden on the formal economy.
Chris Philp, the shadow home secretary, expressed alarm at the report’s findings, calling for increased deportations of illegal migrants. “Having lost control of illegal immigration over the Channel, the Labour government must now urgently start deporting far more illegal immigrants,” Philp stated. “It is totally unacceptable to have these numbers of illegal immigrants in the UK. The law needs to be looked at so that spurious human rights, modern slavery, and asylum claims cannot be used to delay or prevent removals.”
Alp Mehmet, chairman of the think tank Migration Watch, warned that the underreporting of this issue has “colossal implications” for local infrastructure planning. “Utilities, housing, the NHS, GP surgeries, and schools will all come under severe pressure, further risking community cohesion,” Mehmet said.
This report comes amidst rising concerns over illegal Channel crossings. In just the first three weeks of 2025, over 1,000 migrants have crossed the Channel in small boats, surpassing previous years’ figures for the same period. The Home Office reported that on January 23, 129 people arrived in two boats, with 1,019 total crossings so far in 2025. While these numbers are still lower than the record highs of 2022, the frequency of crossings and the risks involved, including fatalities, continue to dominate headlines.
Richard Tice, deputy leader of Reform UK, condemned the figures, calling the situation “totally unacceptable.” He argued that illegal migrants were likely accessing public services funded by taxpayers and working without proper authorization. “It’s another reason why we need to properly control our borders and welcome those who come here legally but thank those who are here illegally as we return them where they came from,” he said.
As the Home Office faces increasing scrutiny, the report underscores the scale of the immigration challenge the UK faces. The government’s next steps will be closely watched by both critics and supporters alike, with significant implications for the nation’s immigration policy, public services, and border security.
