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CrashStats

A420 accidents: crash map and statistics

Police recorded 11,840 collisions on the A420 from 1979 to 2025, with 15,073 casualties. Of those crashes, 236 were fatal and 2,163 serious, and 270 people were killed.

In 2025 there were 119 collisions on the A420, down 25% from 158 in 2024, with 146 casualties.

Collisions since 1979
11,840
62nd highest of 4,923 roads
Casualties
15,073
1.27 per collision
Fatal collisions
236
270 people killed
Serious collisions
2,163
2,544 seriously injured
Collisions in 2025
119
Down 25% on 2024
Casualties in 2025
146
Down 21% on 2024

Crash severity on the A420

On the A420, 2% of collisions were fatal and 18% serious, against 1.6% and 18% across Great Britain.

Collisions by severity, 1979 to 2025

  • Fatal2362%
  • Serious2,16318%
  • Slight9,44180%

Where the A420 ranks among 4,923 roads

Most collisions
62nd
Most casualties
64th
Most fatal collisions
73rd
Most serious collisions
60th

A420 accidents by year

Collisions on the A420 peaked at 440 in 1982 and were down to 119 in 2025.

Collisions and casualties on the A420, 1979 to 2025

  • Collisions
  • Collisions in 2025: 119
  • Casualties

Source: Department for Transport, STATS19 road safety data

View as a table
YearCollisionsCasualties
2025119146
2024158185
2023131156
2022144187
2021131152
2020115141
2019163209
2018163209
2017144178
2016196249
2015180220
2014211272
2013201240
2012207258
2011206273
2010210249
2009201255
2008211257
2007215260
2006232305
2005240306
2004228293
2003264328
2002277354
2001262342
2000292379
1999291409
1998302398
1997287374
1996261328
1995275362
1994227297
1993281344
1992246336
1991291385
1990303435
1989286354
1988279349
1987306374
1986342433
1985356443
1984383492
1983430568
1982440542
1981377490
1980394487
1979382470

When crashes happen on the A420

Friday has the most collisions on the A420 (1,962), and 3pm to 6pm is the busiest time of day (2,830).

Collisions by day of the week

  • Monday1,742 (15%)
  • Tuesday1,708 (14%)
  • Wednesday1,830 (15%)
  • Thursday1,833 (15%)
  • Friday1,962 (17%)
  • Saturday1,664 (14%)
  • Sunday1,101 (9.3%)

Collisions by time of day

  • Midnight to 3am480 (4.1%)
  • 3am to 6am177 (1.5%)
  • 6am to 9am1,565 (13%)
  • 9am to noon1,771 (15%)
  • Noon to 3pm2,098 (18%)
  • 3pm to 6pm2,830 (24%)
  • 6pm to 9pm1,738 (15%)
  • 9pm to midnight1,181 (10%)

Collisions by month

  • January890 (7.5%)
  • February876 (7.4%)
  • March961 (8.1%)
  • April878 (7.4%)
  • May1,020 (8.6%)
  • June1,009 (8.5%)
  • July1,081 (9.1%)
  • August921 (7.8%)
  • September992 (8.4%)
  • October1,141 (9.6%)
  • November1,157 (9.8%)
  • December914 (7.7%)

Light conditions at the time

  • Daylight8,408 (71%)
  • Dark, street lights lit2,531 (21%)
  • Dark, no street lighting740 (6.3%)
  • Dark, lighting unknown108 (0.9%)
  • Dark, street lights unlit44 (0.4%)
  • Not recorded9 (0.1%)

Source: Department for Transport, STATS19 road safety data

Road and weather conditions in A420 crashes

On the A420, 59% of collisions happened where the speed limit was 30 mph and 70% on a dry road surface.

Speed limit at the scene

  • 20 mph1,172 (9.9%)
  • 30 mph6,991 (59%)
  • 40 mph612 (5.2%)
  • 50 mph539 (4.6%)
  • 60 mph2,072 (18%)
  • 70 mph452 (3.8%)
  • Not recorded2 (under 0.1%)

Weather at the time

  • Fine, no high winds9,472 (80%)
  • Raining, no high winds1,474 (12%)
  • Fine with high winds186 (1.6%)
  • Raining with high winds164 (1.4%)
  • Other393 (3.3%)
  • Not recorded151 (1.3%)

Road surface

  • Dry8,295 (70%)
  • Wet or damp3,317 (28%)
  • Frost or ice143 (1.2%)
  • Snow35 (0.3%)
  • Other19 (0.2%)
  • Not recorded31 (0.3%)

Type of road

  • Single carriageway9,242 (78%)
  • Roundabout1,248 (11%)
  • Dual carriageway766 (6.5%)
  • One way street or slip road559 (4.7%)
  • Not recorded25 (0.2%)

Source: Department for Transport, STATS19 road safety data

People hurt and vehicles involved in A420 crashes

Car occupants make up 45% of the people killed or injured on the A420, followed by cyclists (17%).

Casualties by road user

  • Car occupant6,778 (45%)
  • Cyclist2,553 (17%)
  • Motorcyclist2,337 (16%)
  • Pedestrian2,027 (13%)
  • Bus or coach occupant642 (4.3%)
  • Van occupant308 (2%)
  • Other388 (2.6%)
  • Not recorded40 (0.3%)

Vehicles involved

  • Car13,461 (61%)
  • Pedal cycle2,713 (12%)
  • Motorcycle2,493 (11%)
  • Bus or coach1,115 (5%)
  • Van or goods vehicle up to 3.5 tonnes984 (4.4%)
  • Goods vehicle over 3.5 tonnes858 (3.9%)
  • Other555 (2.5%)
  • Not recorded18 (0.1%)

Casualties by age

  • 0 to 5201 (1.3%)
  • 6 to 10306 (2%)
  • 11 to 15546 (3.6%)
  • 16 to 202,811 (19%)
  • 21 to 252,293 (15%)
  • 26 to 353,008 (20%)
  • 36 to 451,990 (13%)
  • 46 to 551,449 (9.6%)
  • 56 to 651,002 (6.6%)
  • 66 to 75629 (4.2%)
  • Over 75418 (2.8%)
  • Not recorded420 (2.8%)

Drivers, passengers and pedestrians

  • Driver or rider9,767 (65%)
  • Passenger3,279 (22%)
  • Pedestrian2,027 (13%)

Source: Department for Transport, STATS19 road safety data

Map of recent crashes on the A420

Map of the 25 most recent crashes on the A420

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

  • 25 crashes
  • Serious
  • Slight

A420 crashes by council area

Collisions on the A420 were recorded in 6 council areas. Oxford has the most, with 4,156, followed by Bristol (2,416) and Vale of White Horse (2,010).

Collisions on the A420 in each area, 1979 to 2025
RankAreaCollisionsCasualtiesFatalSerious
1stOxford4,1564,70839707
2ndBristol2,4162,80023329
3rdVale of White Horse2,0103,207116512
4thWiltshire1,2531,70625274
5thSouth Gloucestershire1,1931,55122226
6thSwindon8021,08311113

A420 crashes by town

Collisions on the A420 were recorded in 11 towns and built-up areas, led by Oxford (4,027) and Bristol (2,054).

Recent crashes on the A420

These are the 25 most recent collisions on the A420, from 6 November to 23 December 2025.

Severity