Speed Camera Data Reveals 23% Rise in Serious Collisions on London’s 20mph Roads

Newly released speed camera enforcement data has revealed a deeply troubling 23 per cent increase in serious collisions on London's 20mph roads over the past twelve months, raising urgent questions about the effectiveness of the capital's flagship speed reduction programme. The figures, obtained through a Freedom of Information request to Transport for London, show that 847 people were seriously injured on roads with 20mph speed limits between April 2025 and March 2026, up from 688 in the previous year.

The Numbers Behind the Crisis

The data paints a concerning picture across nearly every London borough. Southwark recorded the highest number of serious collisions on 20mph roads with 78 incidents, followed by Lambeth with 64 and Camden with 52. Perhaps most alarmingly, the figures show that average speeds recorded by enforcement cameras on 20mph roads have actually increased, with the mean speed rising from 24.3mph to 26.1mph — well above the legal limit.

"These figures are a wake-up call," said Dr Katherine Moss, senior research fellow at the Transport Research Laboratory. "Simply painting a new speed limit on the road without accompanying physical infrastructure changes — such as raised crossings, chicanes, and narrowed carriageways — is clearly not delivering the safety improvements that were promised to Londoners."

TfL Defends Strategy Despite Criticism

Transport for London's Director of Road Safety, Marcus Sheridan, acknowledged the figures were "disappointing" but argued they must be viewed in context. "London's roads are carrying more traffic than ever, and we have also significantly expanded our 20mph network, meaning more roads are now counted in these statistics," he said. "Our long-term data shows that where 20mph limits are properly enforced and supported by engineering measures, we see genuine reductions in both speed and collision severity."

However, critics point out that enforcement remains woefully inadequate. Metropolitan Police data shows that only 12 per cent of London's 20mph roads have any form of speed camera coverage, and the number of speeding tickets issued on these roads fell by 18 per cent last year due to officer shortages and redeployment to other priorities.

Borough Leaders Demand Action

Council leaders from several inner London boroughs have written jointly to the Mayor's office demanding an emergency review of 20mph implementation. Hackney Council leader Philip Glanville said: "We were among the first boroughs to roll out borough-wide 20mph limits, and our residents rightly expect these limits to be enforced. The current approach of relying on voluntary compliance is clearly failing, and we need a fundamental rethink."

Road safety charity Brake has called for mandatory speed limiters on all vehicles operating within the congestion charge zone, a measure already being trialled in several European cities. "The technology exists to prevent speeding entirely," said charity spokesperson Amanda Thornton. "Every day we delay implementing proven solutions, more people are being needlessly killed and seriously injured on London's roads."

Victims' Families Speak Out

Among those calling for change is Sarah Marchetti, 45, whose 12-year-old son Luca was struck by a speeding driver on a 20mph road in Islington last September. Luca suffered a traumatic brain injury and spent three weeks in intensive care at Great Ormond Street Hospital. "The speed limit sign meant nothing to the driver who hit my son," she said through tears. "If the road had proper traffic calming — speed bumps, narrowing, anything — maybe he would have been forced to slow down. These numbers represent real children, real families, real lives destroyed."