Speed limits are a maximum, not a target and depend on the type of road and vehicle you’re driving. The only vehicles that speed limits don’t apply to are those used for fire brigade, ambulance or police purposes while responding to an emergency.
For everyone else, speed limits are a maximum, not a target, and a lower speed may be more appropriate depending on the road layout, traffic and weather conditions.
Mandatory speed limit signs are circular. The road sign for a maximum speed limit shows black numerals on a white background with a red border.
Minimum speed limit sign
You may come across a mandatory minimum speed limit.
At the start, the sign has white numerals on a blue background.
At the finish, there’s a similar sign crossed through with a red diagonal line.
National speed limits
As a general rule, the speed limit is 30mph unless signs say otherwise.
National speed limits for cars, motorcycles, car-derived vans and dual-purpose vehicles, indicated by a circular white sign with a diagonal black bar, are:
60mph (50mph if towing) on a single carriageway.
70mph (60mph if towing) on a dual carriageway.
Expect to see the national speed limit sign at the point where a lower limit ends.
The maximum speed limit on motorways is 70mph (60mph if towing) unless signs indicate otherwise.
Variable speed limits apply on some 'smart' motorways. The signs indicating these are mandatory speed limit signs but produced by lamps, and when not in use they show a blank grey or black face. Limits are likely to be enforced by cameras.
Don't forget that your speed will dramatically alter your stopping distances. The faster you're going, the longer it will take you to stop.
Local limits
Local authorities can set their own limits to address specific local needs. (20mph zones are increasingly common in built-up areas or around a school.) Signs must be clear.
20 mph limits
20mph limits can be introduced where there are significant numbers of pedestrians or cyclists.
Successful limits should be self-enforcing through design (traffic calming) and signing rather than having to rely on additional police enforcement though the police may consider targeted enforcement where there is deliberate offending or disregarding and the limits are clear.
In 2013 the National Driver Offender Retraining Scheme (NDORS) introduced a speed awareness course specifically tailored to speeding offences in 20mph limits where, at the discretion of the police, offenders who are either "mistaken or simply unaware of the limit" would benefit from education.
Penalties
Speeding offences are enforced by the police using fixed, mobile or average speed cameras and are generally dealt with using the Fixed Penalty Notice system.
The minimum penalty for speeding is generally a £100 fine and three points on your licence.
In some areas, at the discretion of the police, and for more minor speeding offences only you might be offered a speed awareness course.
You’ll not be able to attend a course if you’ve done one within the past 3 years.
The course will cost more than the original fixed penalty but if you complete it, you’ll not get the three points on your licence.