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CrashStats

SG4 road accidents: crash map and statistics

Police recorded 4,277 road traffic collisions in the SG4 postcode district, North Hertfordshire, from 1979 to 2025, and 5,803 people were killed or injured in them. Of those collisions, 64 were fatal and 842 were serious.

In 2025 police recorded 33 collisions, down 39% on 2024 (54).

Collisions since 1979
4,277
779th highest of 2,813 postcode districts
Casualties
5,803
1.36 per collision
Fatal collisions
64
66 people killed
Serious collisions
842
962 seriously injured
Collisions in 2025
33
Down 39% on 2024
Casualties in 2025
49
Down 39% on 2024

Road collision statistics for SG4

Collisions by severity, 1979 to 2025

  • Fatal641.5%
  • Serious84220%
  • Slight3,37179%

What the data shows

  • SG4 had 454 collisions from 2016 to 2025, 44% fewer than the 808 from 2006 to 2015.
  • 21% of collisions in SG4 were fatal or serious, against 20% across Great Britain.
  • 553 children under 16 were killed or injured in SG4, 9.6% of the casualties whose age was recorded.
  • The road surface was wet, icy, snowy or flooded in 40% of collisions in SG4.

Where SG4 ranks among 2,813 postcode districts

Most collisions
779th
Most casualties
753rd
Most fatal collisions
819th
Most serious collisions
649th

Collisions by day of the week

  • Monday618 (14%)
  • Tuesday656 (15%)
  • Wednesday616 (14%)
  • Thursday672 (16%)
  • Friday680 (16%)
  • Saturday569 (13%)
  • Sunday466 (11%)

Light conditions

  • Daylight3,130 (73%)
  • Dark, street lights lit636 (15%)
  • Dark, no street lighting457 (11%)
  • Dark, lighting unknown40 (0.9%)
  • Dark, street lights unlit14 (0.3%)

Type of road

  • Single carriageway3,679 (86%)
  • Dual carriageway271 (6.3%)
  • Roundabout257 (6%)
  • One way street or slip road54 (1.3%)
  • Not recorded16 (0.4%)

Speed limit at the scene

  • 20 mph3 (0.1%)
  • 30 mph2,292 (54%)
  • 40 mph99 (2.3%)
  • 50 mph93 (2.2%)
  • 60 mph1,548 (36%)
  • 70 mph242 (5.7%)

Weather at the time

  • Fine, no high winds3,374 (79%)
  • Raining, no high winds564 (13%)
  • Fog or mist65 (1.5%)
  • Raining with high winds61 (1.4%)
  • Fine with high winds53 (1.2%)
  • Snowing, no high winds25 (0.6%)
  • Snowing with high winds7 (0.2%)
  • Other87 (2%)
  • Not recorded41 (1%)

Who was hurt

  • Car occupant3,733 (64%)
  • Motorcyclist770 (13%)
  • Pedestrian501 (8.6%)
  • Cyclist461 (7.9%)
  • Van occupant154 (2.7%)
  • Bus or coach occupant48 (0.8%)
  • Goods vehicle occupant (over 3.5 tonnes)45 (0.8%)
  • Minibus occupant29 (0.5%)
  • Other vehicle occupant29 (0.5%)
  • Taxi or private hire car occupant27 (0.5%)
  • Other6 (0.1%)

Source: Department for Transport, STATS19 road safety data

SG4 road accidents by year

Collisions and casualties in SG4, 1979 to 2025

Collisions in SG4 peaked at 137 in 1986; 2025 had 33.

  • Collisions
  • Collisions in 2025: 33
  • Casualties

Source: Department for Transport, STATS19 road safety data

View as a table
YearCollisionsCasualties
20253349
20245480
20233348
20224670
20213855
20203140
20194969
20185272
20175882
20166084
201583117
201481108
20134152
201273105
20116890
20107499
200971101
200879116
2007108146
2006130183
2005110151
2004104142
2003106158
2002122179
2001123160
2000104145
1999110155
1998132182
1997116154
1996119161
199597139
1994104137
1993112146
1992102132
1991111154
1990126158
1989129170
1988107142
1987103129
1986137187
1985101134
1984108140
1983113156
1982113132
1981103133
198093122
1979110139

Map of recent crashes in SG4

Map of the 24 most recent crashes in SG4

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

  • 24 crashes
  • Fatal
  • Serious
  • Slight

Recent road crashes in SG4

The 24 most recent collisions in SG4 happened between 27 April and 1 November 2025.

Severity

Crashes by road in SG4

The B656 has the most collisions in SG4, 921 of 4,277 (22%), followed by the A602 (493).

Collisions in SG4 on each road, 1979 to 2025
RankRoadCollisionsCasualtiesFatalSerious
1stB6569211,27117212
2ndA602493708891
3rdA505429556271
4thA1(M)176278829
5thB197146205430
6thB651137169235
7thB6525470113
8thA1294513
9thM14500

Council areas covering SG4

Collisions in SG4 were recorded in 5 council areas. North Hertfordshire has 4,216 of 4,277 (99%).

Collisions in SG4 by council area, 1979 to 2025
RankCouncil areaCollisionsCasualtiesFatalSerious
1stNorth Hertfordshire4,2165,72163829
2ndWelwyn Hatfield273706
3rdStevenage162313
4thCentral Bedfordshire6600
5thLuton4501

Towns in SG4

Collisions in SG4 were recorded in 2 towns, led by Hitchin (1,725) and Codicote (131).