We recently became the first UK nation to pass legislation to lower the default national speed limit on residential roads and busy pedestrian streets from 30mph to 20mph when the Senedd voted in favour in July this year. Work is now underway to get Wales ready for that change, as limits will begin to change from September next year.

Here are seven things you may not know about the new 20mph default speed limit:
- Will it improve safety?
Yes, and the evidence is clear. Decreasing speed limits reduces collisions and saves lives. Previous research has shown that there are 40% fewer collisions in areas with 20mph compared with 30mph. In Wales, it has been estimated that with widespread introduction of 20mph, somewhere between 6 to 10 lives would be saved and between 1200 and 2000 casualties avoided each year. The value of preventing these casualties is between £58m and £94m each year.
As well as making collisions less severe when they do happen, the slower speed also increases the chances of avoiding a collision in the first place and reducing the burden on the NHS. Prevention is better than cure!
2. Will it improve the environment and help create safer communities?
Whatever car you have, getting to 30mph requires more than twice as much energy as getting to 20mph. In fact, evidence suggests that as a result of smoother driving styles, reducing braking and acceleration, improved traffic flow, and possible reductions in fuel consumption, 20mph produces less air pollution than 30mph.
People surveyed say that traffic speed is a barrier to walking and cycling for short journeys, so by lowering the speed limit, we’re helping to create safer, quieter, and more pleasant environments where people feel safer to walk and cycle, further reducing air pollution and benefiting people’s health and the local economy. Welsh communities will become better places to live.
3. Do people support it?
People living in communities where 20mph is already the default speed limit are positive about the change. Evidence from a survey conducted on behalf of the Welsh Government showed that the majority of people were in support of the new lower speed limit – almost two thirds of people surveyed said they would support a speed limit of 20mph in the area they live and 55% saying that ‘streets would be a lot nicer for pedestrians with a 20mph speed limit’. 62% of people also said they wanted ‘drivers to slow down a bit on our roads’.
4. Will people observe the limit?
The 30mph speed limit for residential areas was set before World War II, when there were far fewer cars on the roads and speed limits were set without the wealth of research and data that we have now. Research indicates that the vast majority of drivers observe speed limits on residential streets.
5. Is it a blanket approach?
No. Currently 30mph is the default speed limit for streets with street lighting, but there are variations to that limit marked by signs on the road. In the same way, under the new 20mph legislation, local councils can use their local knowledge to retain a 30mph limit where there is a case for doing so. These 30mph roads will be marked by signs in the same way that variations from the current default speed limit are used.
6. Who else is doing this?
The benefits of reducing speeds are becoming recognised all over the world. 120 countries recently signed the Stockholm Declaration on Road Safety, agreeing that reducing the speed limit to 20mph will improve road safety. In 2021 Spain set speed limits in urban streets to 30km/h (equivalent to 20mph) and now other European countries have 30km/h limits for most of their local roads. Closer to home, areas like central London, the Scottish Borders, Lancashire and Cheshire and Chester have made 20mph the default speed limit for residential streets.
7. When will it come into force?
The new 20mph default speed limit will come into force in September 2023. This will arguably be the biggest change to Welsh roads since the wearing of seatbelts was made compulsory in 1983. It is a big change, but like wearing a seat belt, adapting your driving to the new speed limit will become as natural as driving at 30mph is now!
Lee Waters, Deputy Minister for Climate Change
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Darllenwch y dudalen hon yn y Gymraeg.
A waste of money and time. Just because you put a sign up saying 20 do you really think that people will do 20 total waste of money. Spend the money where it’s needed more not waste it on road signs.
If this blanket 20mph limit is so enthusiastically supported then why not prove it and let the people vote on it? Because you will lose and you know it!
Study in Bristol shows it has not improved safety and there is no significant difference between 20, 30 and 40 so stop telling lies
What a load of rubbish. I live in a pilot scheme area and the locals hate it and only 10% comply. It was not in the labour government’s manifesto and disgusting to implement.
Didn’t realise Wales is working with London, thank one of your vans came to help Reg: CV20ECE working. London’s gone downhill
You say that getting up to 30mph uses far more fuel than getting up to 20mph, that may have an element of truth. What you’ve failed to realise is that most people will be entering a 20mph zone from a higher speed so the only time they will be getting up to 30mph is upon exit from your 20mph zones so still using more fuel. If the 20 zone wasn’t there the increased pollution wouldn’t occur. Also traveling along a section of road at 20mph usualy requires a lower gear, so to travel the same distance required the engine to do a greater number of revolution therefore more pollution.
The only thing a 20 zone does is improve safety from collision at the cost of the harm done by increased pollution.
What idiot decided it was better to spend millions on this instead of spending it on health and social care. The people of Wales are not in favour of this. Be prepared to be voted out of office. This is from someone who has voted Labour all my life, not anymore.
Thank you for this excellent bold idea. No one can say it won’t save lives. 30 is way too fast on most residential streets
I fully believe this will make our roads more dangerous.
While driving at 30mph I’ve had people go over the limit to overtake me, so when the limit changes to 20mph, even more people will try overtaking dangerously.
Some cyclists will also try overtaking you and most cyclists I’ve seen tend to ride dangerously anyways as they rarely follow the rules of the road, which to be honest is because schools no longer teach bike safety, or at least not as much.
Also you won’t be able to safely overtake cyclists in time as you’re traveling nearly at the same speed which means it won’t be a 20mph limit, it will be about 13 or 15mph
More people will also try crossing the road when it’s unsafe to do so, which again, can cause more accidents. Where I live almost no one looks before crossing the road.
When the limit is 20mph, if you follow it, you’ll need to look at the speed far more, you’ll need to look at your mirrors more frequently due to cyclists overtaking, you’ll have to pay close attention to pedestrians crossing without looking, you’ll have to pay attention to the cyclist you’ll likely be stuck behind and you’ll have people who won’t follow the 20mph limit behind you beeping, shouting, driving too close and then overtaking you, likely angrily, while shouting, which would dristract you and the other driver from looking at the road, which as you can probably guess, is very dangerous.
The main argument in this article could be solved if people just use their heads. If you cannot safely drive at 30mph, don’t. It’s not a speed target, it is a limit. If everyone just pays attention to the roads, no one will get hurt.
To quote the literal UK governments “You must not drive faster than the speed limit for the type of road and your type of vehicle. The speed limit is the absolute maximum – it doesn’t mean it’s safe to drive at this speed in all conditions.”
This rule only makes sense in VERY dense areas such as Cardiff & Swansea where it’s already 20mph on the roads it needs to be. Where I live, there are many long stretches of empty roads that feel way too slow to drive at 30mph even. Those roads will change to 20 too and it’s not just realistic.
Of course I’ll still follow the limit, I’ll just hate every moment of it.
Where my reply that Assembly needs dissolving ??!
Their all deluded it’s a money making scheme nothing to do with safety or the environment
Are all the signs on posts being changed?. If the post sign is 30 am I restricted to 20 mph?.
Absolute crazy policy, people like Rod King MBE are undoing any credibility of 20mph limits with the only plus being that htis will destroy Welsh Labour.
This is Makr Drakefords Poll Tax
What an absolute load of rubbish. Nearly every point is a lie!
The statistics are flawed by the Governments own admission. Firstly the 30 – 20 mph will only truly reduce speed by 3 mph as the speed averages in these areas are exceeded routinely by motorists and the recorded reduction in pilot areas is in fact just 3 mph. Secondly the so-called savings resulting from possible collisions including injuries and deaths are not actual. Firemen, medics and hospitals are not pay extra or separately for people attending RTC’s for they are on duty anyway. Thirdly in respect of any claim of reduced emissions then as engines rev more in lower gears then fuel consumption and emissions can actually increase with lower speed as lower speed means lower gears in hilly areas. Cardiff will differ significantly with the valleys. All told the claimed benefits are very much unproven – dogma over intelligence!!
the fire service getting to the station will take longer so the lives that are saved will be negated by fire crews taking longer to reach the fire station. also doctors on call, home carers etc. what a load of rubbish.people will spend more time looking at their speedometer which will cause more accidents. will pushbikes be allowing 1 and a half metres space when they overtake (or undertake)?
Propoganda is despicable. One-sided argument is unintelligent at best and potentially dangerous. We should expect more from government ministers and people in power.
Recently travelled from Shrewsbury to Swansea via Newtown, predominantly on the A483 and encountering a plethora of constantly changing speed limit signs, a large number of which appeared to have no relevance whatsoever to the location – a total nightmare!
Additionally, , many signs were obliterated by neglected maintenance of verge side grasses, trees, bushes etc