Speed limits in the UK: know the laws

If you don’t know the ins and outs of the law, you could risk your safety and the safety of others – not to mention face a fine, penalty points or even disqualification.

Remember, ignorance isn’t a defence.

While the Transport Secretary decides whether an 80mph limit would be suitable for our motorways, we’ve researched the current rules and laid them out for you below.

Speed limits were first introduced in the UK in 1861 as part of the Locomotives on Highways Act, and limited vehicles to 10mph. 

The Locomotive Act 1865 reduced this to just 4mph in the country and an agonising 2mph in the city!

Thankfully, things have moved on a bit since then and today UK car speed limits are generally 30mph in urban areas, 60mph on main single-carriageway roads, and 70mph on dual carriageways and motorways.

There are exceptions, however, and many speed limits depend on the type of vehicle. For example, most vans are only allowed to travel at 60mph on dual carriageways and 50mph on national-speed-limit single carriageway roads. As well as this, caravans of any type are only allowed to drive at 30mph in built-up areas.

It’s important to remember that speed limits should be treated as an absolute maximum – it’s not always safe to drive at this speed in all conditions.

The minimum penalty for speeding is a £100 fine and 3 penalty points added to your licence. If you clock up 12 or more penalty points within three years, you could be disqualified from driving.

*What is a car-derived van?

Car-derived vans are a type of van that is based on the same platform as cars, and are typically designed to weigh no more than two tonnes when fully loaded.

They usually look similar to cars, but without rear windows or seats. Popular examples include Vauxhall Corsa and Ford Fiesta vans.

Because these generally drive the same way as cars, they are allowed to follow the same speed limits as standard cars.

Be careful: if you’re not sure whether a van you’re driving is car-derived, check the log book (V5). The ‘body type’ section will tell you whether it’s a car-derived van.

Most vans are not car-derived, and subject to lower speed limits than cars. This includes Ford Transits and the smaller Transit Connect.

• Speed cameras – what you need to know
• Speeding fines – how much you now have to pay
• Motorway cameras – what you need to know

For cars, the national speed limit usually refers to the 70mph limit on motorways and dual carriageways, and the 60mph limit on single carriageways.

The national speed limit sign is a white circle with a single black diagonal stripe through it.

The national speed limit of 30mph on built up roads is signalled on road signs featuring the number within a red circle.

They are often enforced by fixed speed cameras or temporary camera vans positioned in speeding hotspots.

The most serious speeding offences end up in court and could result in a hefty fine or even a driving ban.

Fixed speed limits are the most common kind of speed limit.

These are usually identified by a number within a red circle on road signs entering the speed limited area – such as a ‘30’ when entering an urban area.

Outside 20, 30, 40 or 50mph zones, the majority of UK roads are classed as ‘national speed limit’, denoted by a grey, circular sign with a single, black, diagonal stripe through it.

For cars, 'national speed limit' means a limit of 60mph on single carriageway roads and 70mph on dual carriageways and motorways.

Fixed speed limits are often enforced by fixed ‘Gatso’ speed cameras or temporary camera vans positioned in speeding hotspots.

The most serious speeding offences end up in court and could result in a hefty fine or even a driving ban.

Local councils can introduce their own speed limits – although these must be clearly signed. Look for signs featuring a number within a red circle.

In areas where vulnerable road users such as children and cyclists are frequently found, a 20mph limit is often enforced.

These could be on small residential roads or near schools, and are often enforced by traffic calming measures such as speed bumps and chicanes to physically slow cars down.

Research from 2019 found that 20mph speed limits are only proving effective in areas that also have speed bumps.

On single lane carriageways with sharp bends, local councils can enforce a 50mph limit rather than the usual 60.

Variable speed limits are increasingly being used on so-called ‘smart motorways’ across the UK.

These monitor traffic flow and can make adjustments to reduce congestion when required – for example, by operating the hard shoulder as a live traffic lane, or introducing a temporary speed limit when there’s congestion ahead.

This variable speed limit is displayed on the gantries across motorways, and usually enforced by average speed cameras behind the signs.

They can be introduced for safety reasons, such as during roadworks or if there’s a stranded vehicle ahead, or to slow down traffic and ease congestion further up the motorway.

Variable speed limits are popular on the UK’s busiest motorways, including the M25, M1 and M6.

The penalty for breaking a variable speed limit is the same as for breaking a fixed one.

Minimum speed limits are rare in the UK, but they do exist in places where going too slowly can cause increased congestion or high risk of a crash, such as in tunnels.

They’re marked by a blue, circular sign containing the minimum speed limit, while the end of a minimum speed limit is signalled by the same sign with a red diagonal line through it.

Although there isn’t an official minimum speed limit on most motorways, travelling too slowly can be considered dangerous and you might attract the attention of the police.

In this case, you’d usually be let off with a verbal warning, but you could be prosecuted for careless driving.

It’s a legal requirement for speed limiters to be fitted to vehicles with more than eight passenger seats, such as buses, coaches and limousines, as well as goods vehicles with a maximum laden weight of more than 3.5 tonnes.

They usually work by restricting the fuel supply to the engine when the vehicle reaches its maximum speed, and mean some vehicles aren’t capable of reaching or breaking speed limits.

Many fleet operators also fit them in a bid to reduce CO2 emissions and improve fuel economy.

Most manufacturers are also now offering manual speed limiters, which drivers can set themselves. They’re a useful way to ensure you don’t unintentionally break the limit in, for example, average speed zones.

The European Commission provisionally approved rules that speed limiters will become mandatory for all vehicles sold in Europe from 2022. The Department for Transport say the UK will follow suit, even after our exit from the EU.