Drivers are more likely to break the speed limit in 20mph zones than on any other type of road, according to a major new survey.
The research, involving over 10,500 drivers, found that 44% admitted to speeding in 20mph areas. That’s more than twice the number who said they speed in 50mph zones.
This comes as more local authorities across the UK push for 20mph limits to become standard in residential and urban areas. London has already limited speeds to 20mph on half of its roads. Birmingham – where a third of streets already have the limit – is looking to expand it. Glasgow plans to introduce 20mph zones on all major roads, and the Scottish Government is considering rolling it out nationally.
While reducing speed limits is intended to improve safety, blanket 20mph policies have been controversial. In 2023, Wales introduced a national 20mph limit at a cost of £34 million, only to reverse parts of it less than a year later after public backlash.
Campaign group 20’s Plenty for Us estimates that around 28 million people (one in three UK residents) already live in areas with 20mph limits. Transport for London (TfL) has introduced over 164 miles of 20mph roads since 2018. It recently reported that serious injuries and deaths on borough roads have fallen by 34% since the change – and that traffic flow has not been significantly affected.
Jeremy Leach from 20’s Plenty for Us said: “This backs up evidence from other studies showing that 20mph limits make streets safer and encourage more walking, cycling, and active travel.”
Most Speeding Happens in Residential Zones
Despite these safety benefits, the AA’s latest study reveals that 20mph zones are where drivers are most likely to speed – particularly in residential areas. Alongside the 44% who break 20mph limits, 38% admitted to speeding in 30mph zones. The AA says this is particularly worrying for vulnerable road users, such as pedestrians, cyclists, and schoolchildren.
Outside towns and cities, speeding is less common. In 40mph zones, 24% say they speed. That falls to 21% in 50mph areas and 22% in 60mph zones. On motorways, however, speeding becomes more common again, with 35% saying they go over the 70mph limit.
Speeding on motorways also carries additional risks, especially with the rise of ‘smart motorways’ where speed limits can change suddenly. Ignoring these limits can lead to fines and penalty points.
Why Do Drivers Speed?
When asked how much over the limit they believe is still ‘safe,’ most drivers said up to 4mph over is acceptable in 20–40mph zones. For 50–60mph roads, they said 5mph over was safe, and for 70mph roads, 6mph.
The most common reason drivers gave for speeding was simply not realising how fast they were going – mentioned by 44% of respondents. This was especially common in 20mph and 30mph zones, where drivers either didn’t notice the signage or hadn’t adjusted to the lower speed.
Other reasons included:
- Believing the limit was too low (33%)
- Thinking the road was quiet enough to speed (30%)
- Running late (4%)
- Following the car in front or peer pressure (3%)
Demographic Differences
The research also showed differences in attitudes based on age and gender:
- Men are more likely to speed than women (47% vs. 38%)
- Drivers aged 18–34 are most likely to speed on residential roads
- Those over 65 are the least likely to break speed limits
Call for Better Enforcement and Education
Speeding remains the leading cause of fatal crashes. In 2023, 56% of fatal collisions involved speeding in some form – whether drivers exceeded the limit, went too fast for the conditions, or drove recklessly. That accounts for 809 of the 1,441 road deaths in the UK last year.
The AA says more needs to be done to tackle the issue. It has called for 1,000 more traffic officers and improved driver education. This includes clearer explanations in driving lessons and speed awareness courses about why lower limits are introduced – especially in busy or built-up areas.
AA President Edmund King said:
“Speed kills. Every mile per hour over the limit matters. Whether it’s on a school run or a quiet residential street, the difference between 20mph and 30mph can mean the difference between life and death. Many drivers don’t speed intentionally – they’re just not paying attention. That’s why we need clearer signage, better road markings, and smarter enforcement.”
Local Authorities with Widespread 20mph Limits
County Councils: Cambridgeshire, Lancashire, Oxfordshire
Unitary Authorities: Bath & North East Somerset, Brighton & Hove, Bristol, Cheshire West & Chester, Cornwall, Darlington, East Riding of Yorkshire, Herefordshire, Hull, Leicester, Middlesbrough, Luton, Nottingham, Portsmouth, Southampton, Southend-on-Sea, Warrington, York
Metropolitan Districts: Birmingham, Bolton, Bradford, Bury, Calderdale, Coventry, Doncaster, Leeds, Liverpool, Manchester, Newcastle, Rochdale, Sefton, Sheffield, South Tyneside, St Helens, Stockport, Wigan, Wirral
London Boroughs: Camden, City of London, Croydon, Ealing, Hackney, Hammersmith & Fulham, Haringey, Hounslow, Islington, Kensington & Chelsea, Kingston, Lambeth, Lewisham, Mitcham, Newham, Richmond, Southwark, Tower Hamlets, Waltham Forest, Wandsworth, Westminster
Scottish Authorities: Clackmannanshire, Edinburgh, Fife, Glasgow, Highland, Scottish Borders, West Dunbartonshire
Country-wide: Wales (with partial rollback in 2024)
