Welsh Government's answers to Frequently Asked Questions

Why do you want to introduce a 20mph speed limit on residential roads and busy pedestrian streets across Wales?

Introducing a 20mph default speed limit on residential roads and busy pedestrian streets across Wales will:

save lives and reduce the risk and severity of injuries from collisions between vehicles and vulnerable road users
make streets safer for playing, walking and cycling
encourage more people to make more sustainable travel choices
makes Wales more attractive for our communities
bring physical and mental health benefits
reduce noise pollution, promote cleaner air and be better for the environment

The legislation was approved by the Senedd in July 2022.

What are the benefits of changing the default speed limit?

The evidence from around the world is very clear – reducing speed limits reduces collisions and saves lives. Public Health Wales believe that lowering the default speed limit to 20mph could have substantial health benefits. 20mph will reduce the risk of collisions, help people feel safer and benefit people’s physical and mental well-being. A recent public health study estimated that the 20mph default speed limit could result in:

40% fewer collisions
saving 6 to 10 lives every year;
and avoiding 1200 to 2000 people being injured every year.

Will this affect all roads that are currently 30mph?

These changes will affect most 30mph roads but not all.

This legislation changes the default speed limited on restricted roads. These are generally residential or busy pedestrian streets with streetlights.

But not all 30mph roads are restricted roads, and these remain at 30mph, and will be signed.

For restricted roads, local authorities and the 2 Trunk Road Agencies, can also make exceptions to the default speed limit in consultation with their communities.

We have published a map on DataMapWales that shows which roads would stay at 30mph.

My local area already has reduced speeds of 20mph. Is it part of this initiative?

Many local authorities have already introduced 20mph speed limits across the country due to the recognised benefits and public support. As part of the first phase of the 20mph rollout 8 settlements chose to take part and make their default speed lower:

Abergavenny and Severnside, Monmouthshire
North Cardiff
Buckley, Flintshire
Cilfrew Village, Neath and Port Talbot
St Dogmaels, Pembrokeshire
St Brides Major, Vale of Glamorgan
Llanelli North, Carmarthenshire

You can read the first monitoring report detailing some of the impacts introduction of 20mph has had in these communities. Overall speed has reduced in these areas.

Will the police enforce the proposed 20mph speed limit?

The Police and GoSafe will continue to enforce 20mph, like any other speed limit, to make our roads safer for all users. They will also be helping to engage with and educate motorists to ensure that the new speed limits are respected, and driver behaviour change is supported.

Will reducing the speed limit impact traffic flow?

We do not believe that a 20mph speed limit will increase the number of vehicles driving on the road. Potentially traffic will flow more smoothly.

How will a lower speed limit promote walking and cycling?

Lower speeds mean that people feel more comfortable to walk and cycle and it is safer for children to walk to school. Older people, disabled people or people with additional needs will feel more able to travel independently.

There is evidence from across the world that vehicle speeds are one of the main reasons why people do not walk or cycle or do not allow their children to walk or cycle to school.

How will the new 20mph limit affect pollution?

Study by Imperial College found that 20mph limited areas were “pollution neutral”. Many things contribute to pollution levels. They include:

driving style,
acceleration,
braking,
vehicle condition
distance travelled and
engine temperature.

We believe the lower speed limits will encourage more people to choose active ways to travel and there will be fewer polluting cars on the roads.

Will a reduced speed limit improve safety?

The World Health Organisation states that the most effective way to improve pedestrian safety is to reduce the speed of vehicles.

In the distance a 20mph car can stop, a 30mph car will still be doing 24mph.

From the international evidence base, it can be concluded, on average, a person is around five times more likely to be killed when hit by a vehicle travelling at around 30mph than they are from a vehicle travelling around 20mph.

What effect will the speed limit have on journey times?

Journey times on roads in urban areas tend to be determined by junctions and signals, rather than the speed limit.

In many cases lowering the speed limit to 20mph will have little or no impact on journey times. Where there is an impact, our analysis showed us that most journeys would only be around 1 minute longer but this would make the roads safer for pedestrians and cyclists.

Why can’t the 20mph limit be set up as timed limits during school hours only?

This won’t encourage children to walk or cycle from home, as it would only protect children near the school, where they already have safety in numbers.

80% of child casualties are on non-school trips. Introducing a 20mph default speed limit will make children safer from the moment they leave home – it is designed to make streets safer for everyone.

Will the roll out involve money being spent on speed bumps?

There is no plan to include traffic calming (including speed bumps) as part of the change to speed limits. There are other ‘softer’ measures that might be introduced, such as using buffer speed limits, removing the centre line, narrowing the carriageway visually, using planting etc.

Will reducing speeds to 20mph damage my car?

Modern cars can drive at 20mph without damaging the engine or components.

Accelerating up to a reduced speed of 20mph, and driving at a more consistent speed, should result in lower tyre and brake abrasion and help prolong engine and gearbox life.

Will driving at 20mph mean I use more fuel?

No. 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 twice as much energy as speeding up to 20mph.

A default 20 mph limit and a smooth driving style, can help avoid unnecessary speeding up and slowing down, saving fuel.

Why are bicycles allowed to overtake me when I am driving at 20mph?

Speed limits in the Road Traffic Regulations and the Highway Code apply to motor vehicles only and not to bicycles. However, the Highway Code states that cyclists should be considerate of other road users.

Where else have 20mph speed limits been introduced in the UK?

20mph speed limits are in force in many of the medium and larger cities in England and Scotland and more rural authorities are introducing larger scale extended 20mph programmes.

If Scotland also sets 20mph default speed limits, up to 28 million people in the UK will live in local authorities where 20mph is normal.

You can access this information on the Welsh Government Website