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Rule 124

You MUST NOT exceed the maximum speed limits for the road and for your vehicle (see the speed limits table). A speed limit of 30 mph (48 km/h) generally applies to all roads with street lights (excluding motorways) unless signs show otherwise.

Speed limits

Speed Limits Built-up areas Single carriageways Dual carriageways Motorways
Type of vehicle mph (km/h) mph (km/h) mph (km/h) mph (km/h)
Cars & motorcycles (including car derived vans up to 2 tonnes maximum laden weight) 30 (48) 60 (96) 70 (112) 70 (112)
Cars towing caravans or trailers (including car derived vans and motorcycles) 30 (48) 50 (80) 60 (96) 60 (96)
Motorhomes or motor caravans (not exceeding 3.05 tonnes maximum unladen weight) 30 (48) 60 (96) 70 (112) 70 (112)
Motorhomes or motor caravans (exceeding 3.05 tonnes maximum unladen weight) 30 (48) 50 (80) 60 (96) 70 (112)
Buses, coaches and minibuses (not exceeding 12 metres in overall length) 30 (48) 50 (80) 60 (96) 70† (112)
Goods vehicles (not exceeding 7.5 tonnes maximum laden weight) 30 (48) 50 (80) 60 (96) 70†† (112)
Goods vehicles (exceeding 7.5 tonnes maximum laden weight) in England and Wales 30 (48) 50 (80) 60 (96) 60 (96)
Goods vehicles (exceeding 7.5 tonnes maximum laden weight) in Scotland 30 (48) 40 (64) 50 (80) 60 (96)

† 60 mph (96 km/h) if exceeding 12 metres in overall length.

†† 60 mph (96 km/h) if articulated or towing a trailer.

For speed limits that apply to special types of vehicles, such as oversized vehicles, see Further reading.

Locally set speed limits may apply, for example

  • 20 mph (32 km/h) in some built-up areas
  • 50 mph (80 km/h) on single carriageways with known hazards
  • variable speed limit signs are used on some motorways and dual carriageways to change the maximum speed limit.

Speed limits are enforced by the police.

Rule 124: Examples of speed enforcement

Rule 124: Examples of speed enforcement

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.

Rule 125

The speed limit is the absolute maximum and does not mean it is safe to drive at that speed irrespective of conditions. Driving at speeds too fast for the road and traffic conditions is dangerous. You should always reduce your speed when

  • the road layout or condition presents hazards, such as bends
  • sharing the road with pedestrians, cyclists and horse riders, particularly children, and motorcyclists
  • weather conditions make it safer to do so
  • driving at night as it is more difficult to see other road users.

Rule 126

Stopping distances. Drive at a speed that will allow you to stop well within the distance you can see to be clear.

You should

  • leave enough space between you and the vehicle in front so that you can pull up safely if it suddenly slows down or stops. The safe rule is never to get closer than the overall stopping distance (see Typical Stopping Distances diagram)
  • allow at least a two-second gap between you and the vehicle in front on high-speed roads and in tunnels where visibility is reduced. The gap should be at least doubled on wet roads and up to ten times greater on icy roads
  • remember, large vehicles and motorcycles need a greater distance to stop. If driving a large vehicle in a tunnel, you should allow a four-second gap between you and the vehicle in front

If you have to stop in a tunnel, leave at least a 5-metre gap between you and the vehicle in front.

Rule 126: Use a fixed point to help measure a two-second gap

Rule 126: Use a fixed point such as a sign to help measure a two-second gap

Tailgating is where the gap between you and the vehicle in front is too small for you to be able to stop safely if the vehicle in front suddenly brakes.

Tailgating is dangerous, intimidating and can cause collisions, especially when driving at speed. Keeping a safe distance from the vehicle in front gives you time to react and stop if necessary. Dangerous and careless driving offences, such as tailgating, are enforced by the police.

The Highway Code © Crown copyright. Source: http://gov.uk/highway-code