Latest Government statistics found half of cars and vans exceed the speed limit on motorways and more than one in 10 speed by more than 10mph.
And more than half rigid heavy goods vehicles (HGV) exceeded the speed limit on 30mph roads, with around one in 20 doing so by more than 10mph.
In 2019, under free-flowing traffic conditions, 50% of cars exceeded the speed limit on motorways compared to 54% on 30mph roads and 9% on 60mph roads.
The proportion of cars exceeding the speed limit by more than 10 mph was 12% on motorways but just 6% on 30 mph roads and 1% on 60mph roads.
'Free flow' speeds are observed in locations without external factors that restrict speed such as junctions, hills, sharp bends and speed enforcement cameras.
For all vehicle types, compliance tended to be highest on national speed limit single carriageways and lowest on 30mph roads.
More reassuringly, average car speeds under free flow conditions were close to the speed limit on motorways (69mph) and 30mph roads (31mph) and under the speed limit on 60mph roads (50mph).
The share of fatal and serious accidents where exceeding the speed limit was reported as a contributory factor was 6.6% (1,259) in 2018. This has remained broadly stable since 2013.
There was an 88% conviction ratio for people proceeded against for speed limit offences in England and Wales in 2019 (175,000 were found guilty).
20mph
By their nature, 20mph routes are not likely to be free flow. Department for Transport guidance suggests the limit is most effective when supporting traffic calming measures are installed. As a result, free flow 20mph sites are not representative of most 20mph routes.
Under free flow conditions 86% of cars exceeded the speed limit at the 20mph sites with 20% exceeding the speed limit by more than 10mph.
Why?
A RAC Report on Motoring from 2019 asked users to select up to three reasons why they exceed the speed limit.
Of the five reasons, the top reason given was: 'I drive according to the speed of other road users' and was given by 38% of motorway users and 28% of 30mph road users.
On 20mph roads, users most often cited the speed limit being inappropriate as the contributor to their exceeding the speed limit (33%).
Compliance by vehicle type
Cars
Under freefowing conditions, the proportions of cars complying with the speed limit were 50% on motorways, 91% on national speed limit (NSL) single carriageways and 46% on 30mph roads.
On NSL single carriageway roads 9% of cars exceeded the limit, compared to 54% on 30mph roads and 50% on motorways.
Vans
In free flow conditions, 51% of vans complied with the speed limit and 45% on 30mph road.
On motorways 49% of vans exceeded the speed limit compared to 55% on 30mph roads.
The proportion exceeding the limit by over 10mph on 30mph roads was 6%, while 13% exceeded the speed limit on single carriageways motorways by more than 10mph.
Articulated HGV
In free flow conditions, 99% of articulated HGVs complied with the speed limit on motorways, 73% on NSL single carriageways and 56% on 30mph roads.
The proportion of articulated HGVs exceeding the speed limit by over 10mph on 30mph roads was 3%, while less than 1% exceeded the speed limit by more than 10mph on motorways and NSL single carriageway roads
Rigid HGV
In free flow conditions, 66% of rigid HGVs complied with the speed limit on NSL single carriageways and 53% on 30mph roads.
On NSL single carriageway roads 34% exceeded the speed limit, compared to 47% on 30mph roads.
The proportion exceeding the speed limit by over 10mph on 30mph roads was 5%, and 3% on NSL single carriageways
Motorbike
In free flow conditions, 47% of motorcycles complied with the speed limit on motorways, 74% on NSL single carriageways and 37% on 30mph roads.
The proportion of motorcycles exceeding the speed limit by over 10mph on motorways was 19%, higher than other vehicle types, compared to 16% of motorcycles on 30mph and 10% on NSL single carriageway roads.
The information is based on speed data from a sample of DfT’s Automatic Traffic Counters (ATCs), chosen to exclude locations where external factors might restrict driver behaviour.
