The A406: where people are seriously hurt
Over 2021–2025, 273 people were killed or seriously injured in 257 collisions on the A406, making it the 29th worst numbered road in Britain by that measure.
257
serious or fatal collisions
273
people killed or seriously injured
22
collisions that took a life
#29
of 150 numbered roads
What the record shows
The A406 carries 2,033 recorded injury collisions over the period, 257 of them serious or fatal. Serious injury concentrates in Enfield, Brent, Ealing, with 3 further areas also recording collisions. Its fatal share, 9%, sits close to the 7% average for the numbered network. Most collisions were recorded on 40 mph sections. The worst year of the period was 2024 with 56 serious collisions, and the count is up 17% between 2021 and 2025.
Every serious and fatal collision on the A406
Blue markers are serious collisions, red crosses fatal. Click any marker for the year. Zoom in to see the specific junctions and stretches where they cluster.
Where along the route
- Enfield67 KSI
- Brent45 KSI
- Ealing39 KSI
- Barnet34 KSI
- Waltham Forest22 KSI
- Newham21 KSI
Local authority areas with the most serious collisions on this road.
The trend
Serious and fatal collisions on the A406
2025: 56 (down 0% on the year before) · peak 56 in 2024 · +16.7% across the period
Axis clipped to the data range to show year-on-year movement.
About the A406
How many accidents happen on the A406?
Police recorded 2,033 injury collisions on the A406 over 2021–2025, of which 257 were fatal or serious. Those serious collisions left 273 people killed or seriously injured, including 22 fatal collisions.
Is the A406 a dangerous road?
By volume of serious injury it ranks 29 of the 150 numbered roads we analyse, and 26 among a roads. That is a count rather than a rate: longer and busier roads accumulate more collisions, so a high ranking reflects exposure as well as risk.
Where on the A406 do collisions happen?
They concentrate in Enfield, Brent, Ealing. The map on this page plots every serious and fatal collision recorded on the route, so you can see the specific stretches rather than the total.
Counts include every collision the police recorded on this road number across all authority areas. They are not adjusted for traffic volume or road length, so treat them as a measure of where injury concentrates rather than a per-mile risk rating. Method. Free to reuse with attribution to this page.
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