Statistics of speed of traffic in free flowing conditions in Great Britain. Providing insight into the speeds at which drivers choose to travel and their compliance with speed limits, but should not be taken as estimates of actual average speed across the road network.
Since 2011, average free flow speeds for all vehicle types across each road type monitored have remained broadly stable. The percentage of vehicles exceeding the speed limit for each type of vehicle has generally declined for nearly all vehicle types and road types.
In 2015, on motorways:
- 46% of both cars and light commercial vehicles exceeded the speed limit (70 mph)
- 11% of cars and 12% of light commercial vehicles exceeded the speed limit by 10 mph or more
- the level of speed limit compliance was 99% for articulated heavy goods vehicles (with 60 mph speed limit)
Across all road types, national speed limit single carriageways had the highest level of speed limit compliance for cars in 2015 with 92% of cars not exceeding the speed limit (60 mph).
For all vehicle types, 20 mph roads had the lowest level of speed limit compliance in 2015. 44% of articulated heavy goods vehicles (HGVs) exceeded the speed limit on 30 mph roads.