The A404: where people are seriously hurt
Over 2021–2025, 220 people were killed or seriously injured in 214 collisions on the A404, making it the 37th worst numbered road in Britain by that measure.
214
serious or fatal collisions
220
people killed or seriously injured
9
collisions that took a life
#37
of 150 numbered roads
What the record shows
The A404 carries 1,303 recorded injury collisions over the period, 214 of them serious or fatal. Serious injury concentrates in Brent, Westminster, Buckinghamshire, with 3 further areas also recording collisions. Collisions here are less likely than average to be fatal (4% against 7%), typical of lower-speed urban sections. Most collisions were recorded on 30 mph sections. The worst year of the period was 2022 with 51 serious collisions, and the count is up 52% between 2021 and 2025.
Every serious and fatal collision on the A404
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
- Brent95 KSI
- Westminster55 KSI
- Buckinghamshire23 KSI
- Harrow15 KSI
- Three Rivers9 KSI
- Windsor and Maidenhead8 KSI
Local authority areas with the most serious collisions on this road.
The trend
Serious and fatal collisions on the A404
2025: 47 (up 17.5% on the year before) · peak 51 in 2022 · +51.6% across the period
Axis clipped to the data range to show year-on-year movement.
About the A404
How many accidents happen on the A404?
Police recorded 1,303 injury collisions on the A404 over 2021–2025, of which 214 were fatal or serious. Those serious collisions left 220 people killed or seriously injured, including 9 fatal collisions.
Is the A404 a dangerous road?
By volume of serious injury it ranks 37 of the 150 numbered roads we analyse, and 33 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 A404 do collisions happen?
They concentrate in Brent, Westminster, Buckinghamshire. 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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