M25 motorway congestion hotspots identified near London

New research from Geotab, marking the 40th anniversary of the M25 motorway, has identified significant congestion hotspots that impact business operations and delivery reliability in South East England.

The analysis, which utilized connected-vehicle data from September 2025 to August 2026, found that the eight most congested sections are concentrated between Junctions 10 and 20, specifically around the M3, M4, and M40 interchanges and the Heathrow airport corridor. The worst-performing stretch was identified as the anticlockwise section from Junction 12 to Junction 11, where traffic averaged only 68% of the posted speed limit.

For commercial operators, the unpredictability of journey times presents substantial challenges. A survey of 1,000 van drivers revealed that 25% have declined jobs due to unpredictable travel times, 30% reported customer complaints, and 29% cited increased fuel costs. Despite these delays, 84% of respondents stated their businesses could not operate effectively without the motorway.