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CrashStats

B485 accidents: crash map and statistics

Police recorded 207 collisions on the B485 from 1979 to 2025, with 288 casualties. Of those crashes, 10 were fatal and 53 serious, and 10 people were killed.

In 2025 there were 2 collisions on the B485, up from none in 2024, with 2 casualties.

Collisions since 1979
207
3,208th highest of 4,923 roads
Casualties
288
1.39 per collision
Fatal collisions
10
10 people killed
Serious collisions
53
71 seriously injured
Collisions in 2025
2
Up from none in 2024
Casualties in 2025
2
Up from none in 2024

Crash severity on the B485

On the B485, 4.8% of collisions were fatal and 26% serious, against 1.6% and 18% across Great Britain.

Collisions by severity, 1979 to 2025

  • Fatal104.8%
  • Serious5326%
  • Slight14470%

Where the B485 ranks among 4,923 roads

Most collisions
3,208th
Most casualties
3,176th
Most fatal collisions
1,701st
Most serious collisions
2,886th

B485 accidents by year

Collisions on the B485 peaked at 16 in 1981 and were down to 2 in 2025.

Collisions and casualties on the B485, 1979 to 2025

  • Collisions
  • Collisions in 2025: 2
  • Casualties

Source: Department for Transport, STATS19 road safety data

View as a table
YearCollisionsCasualties
202522
202400
202313
202212
202134
202022
201911
201823
201746
201600
201545
201435
201333
201235
201133
201034
2009711
200835
200744
2006513
200522
200468
200357
2002710
200147
200045
1999712
199811
199768
199645
199522
199436
199322
199245
199156
199013
198922
198877
198744
198658
198537
1984911
198368
19821112
19811623
19801316
19791420

When crashes happen on the B485

Wednesday has the most collisions on the B485 (37), and 6am to 9am is the busiest time of day (42).

Collisions by day of the week

  • Monday32 (15%)
  • Tuesday25 (12%)
  • Wednesday37 (18%)
  • Thursday28 (14%)
  • Friday30 (14%)
  • Saturday23 (11%)
  • Sunday32 (15%)

Collisions by time of day

  • Midnight to 3am11 (5.3%)
  • 3am to 6am3 (1.4%)
  • 6am to 9am42 (20%)
  • 9am to noon36 (17%)
  • Noon to 3pm26 (13%)
  • 3pm to 6pm36 (17%)
  • 6pm to 9pm31 (15%)
  • 9pm to midnight22 (11%)

Collisions by month

  • January23 (11%)
  • February11 (5.3%)
  • March20 (9.7%)
  • April17 (8.2%)
  • May14 (6.8%)
  • June21 (10%)
  • July15 (7.2%)
  • August13 (6.3%)
  • September20 (9.7%)
  • October18 (8.7%)
  • November20 (9.7%)
  • December15 (7.2%)

Light conditions at the time

  • Daylight145 (70%)
  • Dark, no street lighting46 (22%)
  • Dark, street lights lit11 (5.3%)
  • Dark, lighting unknown4 (1.9%)
  • Dark, street lights unlit1 (0.5%)

Source: Department for Transport, STATS19 road safety data

Road and weather conditions in B485 crashes

On the B485, 74% of collisions happened where the speed limit was 60 mph and 57% on a dry road surface.

Speed limit at the scene

  • 30 mph37 (18%)
  • 40 mph2 (1%)
  • 50 mph14 (6.8%)
  • 60 mph154 (74%)

Weather at the time

  • Fine, no high winds161 (78%)
  • Raining, no high winds23 (11%)
  • Fine with high winds3 (1.4%)
  • Fog or mist2 (1%)
  • Other18 (8.7%)

Road surface

  • Dry119 (57%)
  • Wet or damp66 (32%)
  • Frost or ice18 (8.7%)
  • Oil or diesel2 (1%)
  • Snow2 (1%)

Type of road

  • Single carriageway203 (98%)
  • Dual carriageway3 (1.4%)
  • Not recorded1 (0.5%)

Source: Department for Transport, STATS19 road safety data

People hurt and vehicles involved in B485 crashes

Car occupants make up 76% of the people killed or injured on the B485, followed by motorcyclists (9.4%).

Casualties by road user

  • Car occupant219 (76%)
  • Motorcyclist27 (9.4%)
  • Cyclist13 (4.5%)
  • Pedestrian11 (3.8%)
  • Goods vehicle occupant (over 3.5 tonnes)8 (2.8%)
  • Van occupant7 (2.4%)
  • Taxi or private hire car occupant2 (0.7%)
  • Minibus occupant1 (0.3%)

Vehicles involved

  • Car290 (77%)
  • Motorcycle29 (7.7%)
  • Goods vehicle over 3.5 tonnes16 (4.3%)
  • Pedal cycle16 (4.3%)
  • Van or goods vehicle up to 3.5 tonnes14 (3.7%)
  • Other vehicle4 (1.1%)
  • Other4 (1.1%)
  • Not recorded2 (0.5%)

Casualties by age

  • 0 to 51 (0.3%)
  • 6 to 103 (1%)
  • 11 to 158 (2.8%)
  • 16 to 2069 (24%)
  • 21 to 2531 (11%)
  • 26 to 3547 (16%)
  • 36 to 4544 (15%)
  • 46 to 5543 (15%)
  • 56 to 6522 (7.6%)
  • 66 to 7512 (4.2%)
  • Over 756 (2.1%)
  • Not recorded2 (0.7%)

Drivers, passengers and pedestrians

  • Driver or rider210 (73%)
  • Passenger67 (23%)
  • Pedestrian11 (3.8%)

Source: Department for Transport, STATS19 road safety data

Map of recent crashes on the B485

Map of the 25 most recent crashes on the B485

Use the arrow keys to move the map and the plus and minus keys to zoom.

  • 25 crashes
  • Serious
  • Slight

B485 crashes by council area

Of the 207 collisions on the B485, 204 were in Buckinghamshire.

Collisions on the B485 in each area, 1979 to 2025
RankAreaCollisionsCasualtiesFatalSerious
1stBuckinghamshire2042831052

B485 crashes by town

Of the 207 collisions on the B485, 24 were in the built-up area of Chesham.

Recent crashes on the B485

These are the 25 most recent collisions on the B485, from 24 June 2013 to 22 June 2025.

Severity