Road Speed Limits

Road Speed Limits

Road Speed Limits

Road Speed Limits

April 18, 2020

Road Speed Limits

Road Speed Limits in the UK – What, Why, When?

34.4 mph – the perfect speed for exploring?

Sometimes all it takes is one unexpected question to challenge your entire understanding of a topic.

In this regard, a comment on a speeding fines article, which questioned how speed limits are measured, started out as a bit of an oddity, but it set the CLM team off on a voyage of discovery.

So what was this now infamous comment?

How is it that speeds are always quoted in whole numbers, never 34.4 for example?

Shrugs of shoulders (because they are?) were soon followed with further puzzlement. The suggestion that speed wouldn’t be a whole number is interesting and not something that had come up before. Why are they always whole numbers?

A little more research suggests that there are a lot of questions out there about UK speed limits.

So how long have the speed limits been in place? Aren’t the rules changing for motorways soon, maybe they’ll increase the dual carriageway speed restrictions too? Yes, I heard that too, but the limit will still be lower than on German autobahns.

How do I find the speed limit on a road? What are the speed limits on UK roads? Can Google Maps show the speed limit? How much over 70 mph can you go?

So, we’ve pulled together some information on all matters speed limits UK!

Note: we have existing articles which cover speeding penalties and fines, and smart motorways. So rather than repeat ourselves, there are links to those at the end so you can read more if you wish.

A brief history of speed limits

Let’s start with the fundamental question, why do we have them?

This question is straight forward enough, with restrictions primarily being used to increase road safety for drivers and other road users. Environmental and accessibility reasons also play a part in why we have maximum speed limits set and how they are deployed. During the oil crisis in 1973, there was even a reduction in speed rules in an attempt to curb fuel consumption.

Let’s take a brief look at the evolution of speed limit rules in the UK.

history of speed limits

What we have seen is that up until the 1970s the speed limits in Britain have evolved significantly, typically in line with improvements in-vehicle technology. With the vehicles of today being almost unrecognisable from those of 50 years ago, it does pose the question as to why the speed limits have stopped evolving too.

One answer which was put forward by Highways England in 2018 is that the vast majority of the public do not want speed limits to increase, in particular, that “it would need to become socially acceptable before the limit is changed”.

Who sets the speed limits?

As shown in the timeline of speed limit changes, throughout history there have been several parties who have been able to effect change upon the UK’s motorists. The situation today is relatively stable with the rules set out in the Highway Code (Control of the vehicle – specifically rule 24):

You MUST NOT exceed the maximum speed limits for the road and for your vehicle (see the speed limits table). The presence of street lights generally means that there is a 30 mph (48 km/h) speed limit unless otherwise specified.

The Highway Code, in turn, takes direction from UK law, specifically “Road Traffic Regulation Act” sections 81, 86, 89 & schedule 6 as amended by MV(VSL)(E&W).

Therefore any changes (decimal place or otherwise) would require a full legislative process with a bill passing through the relevant houses.

The story doesn’t end there though, as we have a subsection of the law which allows for locally set speed limits, granting local councils the ability to set their own rules in certain areas. This power is limited to reducing (not increasing) nationally imposed limits and each amendment is put through a centralised review process. Examples that you will be familiar with include; 20 mph zone in built-up areas near a school and 50 mph section on a 60 mph carriageway with sharp bends.

Recently, an increasing number of councils are considering or have actioned reduced speed limits to tackle vehicle emissions. One example of this saw Surrey and Hampshire councils join forces to reduce the limit on the A331 dual carriageway from 70 mph to 50 mph. The new limit was approved despite the changes not receiving the support of the police who expressed reservations.

compulsory speed limiter intelligence speed assistance

Other speed-related questions

How do I find the speed limit on a road?

On UK roads, maximum speed limits are indicated by roadside signs which show the number on a circular sign with a red border.

These signs are shown as you enter a new limit and may be displayed at intervals along the road – either on lamp posts or free-standing poles for single carriageway or dual carriageways. On motorways, the national speed limit applies unless advised otherwise by signs. Drivers will increasingly find variable speeds in use on motorways, displayed on the gantries over motorways, and frequently enforced by average speed cameras.

In built-up areas, the presence of street lights generally means that there is a 30 mph speed limit unless signs say otherwise.

This link lists the speed limits applicable to different vehicles:

What are the speed limits on UK roads?

Speed limits are determined by the road type, i.e. single carriageways, dual carriageways, motorways; whether it is in a built-up area; and/or the vehicle type.

You must not drive faster than the limit for the type of road and your type of vehicle. And note that this is a maximum and not a minimum speed limit! You must also take into account the road conditions, weather, etc and drive safely.

National speed limits are determined by the road type:

  • Single carriageways
  • Dual carriageways
  • Motorways

And type of vehicle:

  • Cars, motorcycles, car-derived vans and dual-purpose vehicles
  • Motorhomes or motor caravans
  • Buses, coaches and minibuses
  • Goods vehicles

There are variations based on vehicle weight, e.g. under 7.5 tonnes or over 7.5 tonnes, and vehicle length so check for your specific vehicle.

It also varies when towing a trailer – and there are different rules in England and Wales, and Scotland

Here’s the table showing National Speed Limits. Note that local variations can apply.

Can Google Maps show the speed limit?

There were media reports in May 2019 that Google was adding the ability to see speed limits and speed traps in 40+ countries in Google Maps. However, it may have been either a test, on a gradual roll-out, or subsequently withdrawn. Users who could access it reported inconsistencies and, at the time of writing, it does not appear to be available in the UK.

How much over 70 mph can you go?

Many of the questions we’ve seen around this topic relate to how the maximum driving speeds can be exceeded. While there are reportedly buffers applied to give a margin for error, the maximum is still the maximum in the law. So, the short answer is that you can’t, legally, in the UK.

Is there a minimum speed limit?

There is no official national minimum speed limit set, although there are occasionally mandatory sections on major roads where such a restriction applies. This will be indicated by a blue circular sign, showing the number in white. At the end of the section, the sign is displayed with a red line crossing it.

Be aware that, regardless of the limit, it is possible to be fined for driving too slowly if you are considered to be dangerous to other road users.

smart motorway m25 speeding limits

Punishments for speeding

Penalties for speeding in the UK are grouped into A, B and C categories which depend on how far over the speeding limit a vehicle is. The penalties escalate through these categories ranging from compulsory education programmes, to points on a driving licence with accompanying cash fines or ultimately a trip to court leading to a driving ban.

However, despite these penalties, speeding is rife, albeit perhaps only on certain types of roads, under given conditions. In June 2019, the Department for Transport produced a report which showed that, under free-flowing traffic conditions, 46% of cars exceeded the limit on motorways, compared to 52% on 30 mph roads and 10% on 60 mph roads.

This leads us to the question, are punishments for speeding not strong enough to discourage drivers or is it that the relatively low risk of being caught that encourages drivers to drive too fast? Have your say in our poll.

Create your own user feedback survey

Picking up the earlier mentioned Highways England comment that an increase in national speed limits would be unpopular in the court of public opinion, we have a direct contradiction with what actually seems to happen when drivers get behind the wheel. The Select Committee on Transport noted this dichotomy in a 2002 report:

The problem is that most drivers and pedestrians think speeds are generally too high but 95 per cent of all drivers admit to exceeding speed limits”.

The challenges of balancing, safety, environmental concerns, public opinion and driver’s rights remains a tricky topic for lawmakers. This conundrum will surely intensify in the future as vehicle technology develops further and self-driving vehicles become more prevalent and have greater autonomy.

That debate is the right point to draw a line under this article, but before we do, we’ll return to the question which started this.

In researching the topics covered in this post we discovered that e-bikes that are fitted with an electric motor can only be driven without a licence or insurance if; their power is limited, and the motor automatically switches off at speeds above 15.5 mph!

To read more about related topics, here are two other articles you may find interesting:

Speed Limits on Smart Motorways

Beware of Speeding on Smart Motorways Word is that, from midnight on the 8th January 2019, all of the Active Traffic Management (ATM) system cameras that monitor speeding on ...