The A4040: where people are seriously hurt
Over 2021–2025, 161 people were killed or seriously injured in 144 collisions on the A4040, making it the 71th worst numbered road in Britain by that measure.
144
serious or fatal collisions
161
people killed or seriously injured
10
collisions that took a life
#71
of 150 numbered roads
What the record shows
The A4040 carries 795 recorded injury collisions over the period, 144 of them serious or fatal. Serious injury concentrates in Birmingham, Windsor and Maidenhead. Its fatal share, 7%, sits close to the 7% average for the numbered network. Most collisions were recorded on 30 mph sections. The worst year of the period was 2023 with 35 serious collisions, and the count is down 18% between 2021 and 2025.
Every serious and fatal collision on the A4040
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
- Birmingham143 KSI
- Windsor and Maidenhead1 KSI
Local authority areas with the most serious collisions on this road.
The trend
Serious and fatal collisions on the A4040
2025: 23 (down 34.3% on the year before) · peak 35 in 2023 · -17.9% across the period
Axis clipped to the data range to show year-on-year movement.
About the A4040
How many accidents happen on the A4040?
Police recorded 795 injury collisions on the A4040 over 2021–2025, of which 144 were fatal or serious. Those serious collisions left 161 people killed or seriously injured, including 10 fatal collisions.
Is the A4040 a dangerous road?
By volume of serious injury it ranks 71 of the 150 numbered roads we analyse, and 65 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 A4040 do collisions happen?
They concentrate in Birmingham, Windsor and Maidenhead. 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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