Cornwall is one of the first rural areas to reduce speed limits from 30mph to 20mph on residential roads and in built-up areas. It will make roads, safer, healthier, greener, and ultimately, better for everyone.
After a successful pilot (Phase 1) in Camelford, Falmouth and Penryn during 2022, a countywide roll out programme has been approved.
Cornwall Council aims to reduce both death and serious injury by 50% on our roads by 2030, and 20mph limits will support this.
The benefits of reducing speeds to 20mph
There is strong evidence that driving at 20mph makes roads safer. In Bristol, lowering speed limits to 20mph led to 63% fewer deaths. In Edinburgh, a city-wide 20mph limit reduced injuries by 39% in one year. A study in 2024 found that 20mph speed limits in 40 European cities reduced fatalities by 37%, and injuries by 38%.
Research shows that there is a clear relationship between traffic speed and the severity of injury in the event of a collision. If a pedestrian is hit by a car travelling at 19mph, on average, there is around a 5% risk of a fatality. This risk increases over five times at 30mph.
Lower speeds save lives, and this is why we are reducing speed limits in residential and built-up areas, to 20mph.
Travelling at 20mph provides many other benefits too:
- Increasing child and adult activity levels. This will improve health and wellbeing.
- Providing a safer environment. This will encourage more people to walk and cycle.
- Supporting climate change declaration. This will include lower emissions and tackling congestion, as well as supporting our ambition to be Carbon Neutral by 2030.
- Creating a stronger sense of community as more people come together to use the space.
Walking and cycling
Villages, towns and cities should be places where people are free to travel in ways that are:
- Safe
- Sustainable
- Healthy
- Fair
Higher speeds negatively impact safety where people live, work and play. This particularly affects our more vulnerable road users such as children and the elderly.
Lower speeds improve both actual and perceived safety and may mean people feel more comfortable to walk and cycle. Children will also have a safer environment to walk to school and the elderly will feel more able to travel safely.
Lower speeds benefit air quality
Air pollution causes 28,000 to 36,000 deaths every year in the UK. Lower speeds are better for air quality. There is little proof that driving at 20mph makes more pollution.
It's not just about driving longer; how you drive matters too. Speeding up and braking a lot makes more pollution.
Up to 75% of pollution from cars comes from tyres and brakes, not exhausts.
Driving slower helps people drive more smoothly, which lowers pollution. Roads with 20mph speed limits help reduce this by making cars speed up less often, which leads to fewer emissions.
More people walking or cycling instead of driving also helps. A study in 2024 found that 20mph speed limits in 40 European cities cut emissions by 18%. Other research has found that slowing down from 30mph to 20mph cut CO₂ emissions by up to 37.8% and NOx emissions by 51.0%.
This didn't make trips much longer. Different driving styles, car sizes, and fuel types also affect pollution.
Journey times
Journey times on roads in urban areas tend to be determined by junctions, crossings and parked vehicles, rather than speed limits. Often lowering the speed limit to 20mph will have little or no impact on journey times.
Where there is an impact, this would be negligible, but in turn would make the roads safer for everyone; including pedestrians and cyclists.
Bus journey times were reviewed during Phase 1 and were found to be negligible. We will continue to monitor bus journey times throughout the programme.
Less acceleration and braking smooths traffic flow, reduces gaps between cars and reduces idling.
Lower speeds benefit noise pollution
Noise research studies show about a 3 decibel (dB(A)) reduction when reducing a 30mph speed limit to 20mph. This is perceived as halving ambient noise.
The impact on fuel consumption
Fuel consumption is mainly influenced by the way we drive. Driving at a consistent speed is better than stopping and starting. Accelerating up to 30mph can take over twice as much energy as accelerating up to 20mph.
A 20mph speed limit and a smooth driving style, can help avoid unnecessary speeding up and slowing down, saving fuel.
Research from Future Transport shows fuel efficiency peaks with speed capped at 20mph. The 'real life' model factors in stop/start urban traffic and shows that drivers can save up to 10p a mile on fuel; a 30% saving in urban fuel costs.
Where 20mph won’t be introduced
We will review all roads on a case-by-case basis where the existing limit is 30mph, with the intention to reduce to 20mph. Urban areas with high pedestrian and cyclist movements will be prioritised.
This could include areas around schools, shops, markets, playgrounds.
For some roads, it may be appropriate to keep 30mph or deliver a more focused 20mph section. This will be a considered decision, based on local circumstances.
Exceptions will generally be major roads and where vehicles are the primary function.
An exceptions process and associated assessment criteria has been developed, which helps to support this process.
Speed limits higher than 30mph will not qualify for 20mph. We appreciate that communities with speed limits of 40mph or above, may face difficulties.
There may be opportunities to improve the local environment through other initiatives. For example, the Community Highway Scheme.
Police enforcement
Devon and Cornwall Police can and will enforce 20mph limits. The Traffic Regulation Orders associated with this programme will support this. Enforcement will be carried out in places where the new speed limits are regularly being broken, and where there is a risk of injury to other road users.
Enforcement has already taken place in a number of new 20mph areas.
Road safety is something all road users have responsibility for. Road user respect and positive driver behaviour is crucial. Whether you live in a 20mph or travel through 20mph, we ask you to stick to those limits in place.
Police 20mph Enforcement Position Statement
Why our approach is different to Wales
In Wales, the law changed the default speed limit on restricted roads from 30mph, to 20mph. Restricted roads are usually in residential and built-up areas where there are lots of people, and often have street lights on them placed no more than 200 yards apart.
In Cornwall, each 30mph speed limit is being assessed on a case by case basis. The majority of roads will be reduced to 20mph. However, not every road is appropriate for 20mph, so some roads will remain at 30mph.
We are taking a very careful and considered approach. We are listening to our communities through:
- early meetings held with Cornwall Councillors and Town/Parish Councils
- statutory public consultation
If you see a 20mph limit in place across Cornwall there is a good reason for it, it just may not be immediately apparent. There may be a school or playground entrance set back from the road for example.
Costs of the 20mph programme
The countywide programme is estimated to cost £4m.
The Department for Transport estimate the real costs linked with collisions. These include costs of lost output, medical and ambulance, police, insurance and admin, and damage to property:
- £2.72m per fatal collision
- £311,098 per serious collision
- £31,132 per slight collision
Speed was recorded as a contributory factor in 189 collisions across Cornwall between 1st January 2020 and 31st December 2022. All of these were within 30mph limits. Of the 189 recorded injury collisions:
- 4 were fatal (£10.9million)
- 43 were serious (£13.37m)
- 143 were slight (£4.45m).
Introducing slower speeds will reduce collisions. It will also support economic savings through reduced lost output costs. Ultimately, we want to help prevent those tragic knocks on the door that no family or friends want.
Timelines for the rollout of 20mph
Statutory public consultation will be undertaken for each phase of delivery.
Using road collision and casualty data we have identified the priority order for the rollout.
2022/23
- Falmouth and Penryn - Complete
- Camelford - Complete
2023/24
- Camborne, Pool, Illogan and Redruth - Complete
- West Penwith - Complete
- Truro and the Roseland - Complete
2024/25
- Hayle and St Ives
- St Austell and Mevagissey
- Newquay and St Columb
- Cornwall Gateway - Complete
- Liskeard and Looe
- China Clay - Complete
2025/26
- Helston and South Kerrier
- Bude
- Launceston
2026
- Wadebridge and Padstow
- Bodmin
- Caradon
- St Blazey, Fowey and Lostwithiel
- St Agnes and Perranporth
Life's better at 20mph resource pack
Community support has proven integral to the successful implementation of 20mph limits elsewhere.
We have created a resource pack to help spread the word and engage your community at a local level. This will support the work of the wider campaign to make Cornwall's roads safer.