Most drivers speed on 20mph ‘free-flowing’ roads in England
The latest vehicle speed compliance statistics published by the Department for Transport found that on ‘free-flowing’ roads with a speed limit of 20 miles per hour, most drivers are liable to speed.
The data showed that under free flow conditions, 76% of cars exceeded the speed limit at 20mph road sites where data is available, and 10% exceeded the speed limit by over 10mph.
It is important to note that this data refers to ‘free-flowing’ roads, or roads without the impediments and traffic calming measures commonly found on 20mph roads in England. Free flow speeds are usually observed in locations where external factors which might restrict driver behaviour (for example junctions, hills, sharp bends, and speed enforcement cameras) are not present.
The Department for Transport said 20mph speed limits are most effective when they have traffic calming measures or when average vehicle speeds are already below 24 mph, and that by their nature, roads with 20mph speed limits are likely to have traffic calming or by their layout not be designed as ‘free flow’.
This means that quieter residential streets with 20mph speed limits are underrepresented in this data, and the ‘free-flowing’ 20mph roads included in the data set will likely be unrepresentative of 20mph roads in general.
According to the RAC Report on Motoring 2024, when asked to select reasons for why they were speeding on 20mph roads, most UK drivers said the speed limit was inappropriate for that road.
This reason was cited by 52% of 20 mph road users who admitted to breaking the speed limit.
Beyond its data on 20mph free-flowing roads, the Department of Transport found that on other roads measured – 30mph roads, national speed limit single carriageways, and motorways – the percentage of vehicles exceeding the speed limit has generally declined.
This is true for cars, vans, and motorcycles, with heavy goods vehicles’ speed exceedance remaining roughly the same over time.
