These statistics provide insight into the speeds at which drivers choose to travel and their compliance with speed limits under free flow conditions but should not be taken as estimates of actual compliance or actual average speed across the wider road network.
Speed compliance has overall remained consistent since 2011, although between 2016 and 2017, there were minor increases in vehicles exceeding the speed limit.
- 48% of cars exceeded the speed limit on motorways
- 9% of cars exceeded the speed limit on national speed limit single carriageways
- 52% of cars exceeded the speed limit on 30mph roads
- 86% of cars motorcycles exceeded the speed limit on 20mph roads
Similar relative patterns were seen for most vehicle types. Speed limit compliance was lowest on 20mph roads for all vehicle types, for the majority of vehicle types, highest on national speed limit single carriageways.
Vehicle Headway data has been expanded to include cars, vans, motorcycles and buses. A lower proportion of cars (66%), vans (66%) and motorcycles (60%) were observed leaving the minimum recommended two second gap between themselves and the vehicle in front than articulated Heavy Goods Vehicles (87%), rigid HGVs (76%) or buses (80%).
For all vehicle types, average free flow speeds were very close to the appropriate speed limits on 30mph roads (27 to 32mph), above the speed limit on 20mph roads (21 to 27mph) and under the speed limit for most vehicles types on motorways and national speed limit single carriageways.