UK speed limits explained: how fast can I drive?

Wales has introduced a new default speed limit of 20mph on most of its roads. The move, which is aimed at cutting accidents as well as emissions, has attracted strong opinions on both sides. Supporters say the decision could lead to 20,000 fewer casualties on Welsh roads, while opponents point to a potential economic impact from fewer tourists.

While the new 20mph speed limit applies to all roads in Wales which were previously limited to 30mph, that doesn’t mean that all 30mph roads in the country are now limited to 20mph – local authorities have been able to keep roads at the previous limit if they want to. That means that some busy routes, such as the North Road and Newport Road in Cardiff, have been kept at the 30mph limit.

Scotland could follow Wales in making 20mph the default limit for urban roads, with an agreement between the ruling political parties in the country agreeing to expand current 20mph to all of Scotland by 2025.

There are no current plans to adopt a 20mph default speed limit in England.

In this story, we’ll look at the different speed limits in force across the UK, as well as the potential speeding fines and penalties drivers face for abusing them.

UK national speed limits

Depending on what sort of road you’re driving on, you could see different speed limits. These are the most common limits on UK roads.

Residential and school zones – These areas use 20mph limits across the UK, and are designed to slow traffic down around areas where children are likely to spend a lot of time walking, or where there is lots of residential traffic.

Built-up areas – Across most of the UK, urban roads in built-up areas typically have a speed limit of 30mph. However, in Wales, that limit has been lowered to 20mph for roads where local councils haven’t specifically applied a 30mph limit. 

Single-lane carriageways – Typically found in the countryside or on A-roads, cars are usually limited to 60mph. Larger vans or lorries, or vehicles being used to tow, may face other restrictions, so it’s worth checking before you travel.  

Dual carriageways and motorways – These are the fastest public roads in the UK, and have a speed limit of 70mph. Again, if you’re driving a large van, a lorry, or towing, then lower limits may apply.   

While minimum speed limits are rare, they do exist on certain routes to ensure the smooth and safe flow of traffic. Examples of routes with minimum speed limits include the Dartford Tunnel, which has a 10mph minimum limit, and the Kingsway and Queensway Mersey Tunnels, which have limits of 10mph and 20mph respectively.

What speed limits exist for different cars?

No matter what type of vehicle you’re driving, the legal speed limit in built-up areas in England, Scotland and Northern Ireland is 30mph, or 20mph in built-up areas in Wales.

Cars, motorcycles, car-derived vans and dual-purpose vehicles can travel up to 60mph on single-lane carriageways, or 70mph on dual carriageways and the motorway.

Cars which are towing can travel up to 50mph on single-lane carriageways, or 60mph on dual carriageways and motorways.

There are different rules for commercial vehicles. The speed limit for a van, for example, varies depending on what you're carrying and how heavy your van is. There are also separate rules covering speed limits for campervans and motorhomes.

How are speed limits enforced?

Speed limits across the UK are enforced using speed cameras, which can either be in permanent positions or deployed from mobile police enforcement vans. At any one time there can be as many as 7000 active speed cameras across the UK.

While there are more than 14 different types of speed cameras available – including some using Artificial Intelligence – most work by taking at least one photo of your car if it detects that you’re moving above the speed limit. 

The penalties for being caught speeding can be severe, with a minimum fine being £100 and three penalty points on your driving licence. While in some cases you may be able to avoid points by opting to take a speed awareness course, this largely depends on the police force handling your offence.

How to stay within the speed limit

While you might think that staying below a certain speed would be easy, doing so without spending all of your time looking at your car’s speedometer can be difficult. These tips should help you to avoid falling foul of the law.

1. Use technology: Many cars come with cruise control, which keeps you at a set speed, while most modern cars are available with adaptive cruise control, which adds to this by automatically slowing you down if you’re following another car. If you drive a car with a head-up display, these project your current speed directly into your line of sight.

2. Navigation apps: If you use sat-nav apps such as Waze or Google Maps while driving, then these also give you an accurate readout of how fast you’re going. Every time you glance at the map, you can also check your speed and adjust it if needed.

3. Check your speedometer: You don’t need to bury your head in your car’s instrument cluster to keep an eye on your speed – a quick glance every few seconds should suffice.

4. Avoid distraction: Whether it’s children, other passengers or loud music, try to avoid not keep an eye on your speed. Doing so – especially if you’re coming up to a speed camera – could have costly consequences.  

Your speed limit questions answered

What roads are now 20mph in Wales?

All roads which previously had a 30mph speed limit in Wales are now set to 20mph, unless local authorities have applied to keep the roads at 30mph. Generally speaking, that means most roads in built-up areas in Wales now have a speed limit of 20mph.

What is the speed limit in Wales?

Most urban roads have a default speed limit of 20mph. For cars, the speed limits on single-lane carriageways, dual carriageways and motorways remain the same as for the rest of the UK, with the maximum speed most cars can legally travel on public roads set at 70mph.

Can I drive at 80mph on UK roads?

No. The maximum speed any vehicle can legally travel on UK public roads is 70mph. Although there have been calls for the Government to revisit the national speed limit with a view to raising it to 80mph, no firm plans have been put in place.

Will I get caught doing 75mph on the motorway?

While any speed above 70mph is classed as speeding, it's suggested that most police forces use a tolerance of 10% plus 2mph above the speed limit before a speed camera will ‘catch’ a motorist. That means cameras can activate at 35mph if the speed limit is 30mph, or 79mph if the speed limit is 70mph. However, that doesn’t mean you should drive at those speeds.

How accurate is my car’s speedometer?

It has been suggested that some car speedometers can over-read by as much as 10%, meaning if that car shows that you’re travelling at 70mph, you could actually be doing as little as 63mph. While it is illegal for a car’s speedometer to under-read and show you as doing a speed that’s slower than you’re actually doing, it’s not illegal for a speedometer to over-read. Again, you should not account for the potential over-reading of your car's speedometer when deciding how fast to drive.

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