30 mph speed limit sign: what it means

30 mph speed limit sign: a white circle with a red ring and the number 30 in black
Image: Crown copyright, OGL

The 30 mph sign means the maximum speed is 30 mph from that point. It is a limit, not a target, so drive slower when conditions need it.

Take the free road signs quiz

Last checked against the sources: · Report a mistake

What it means

A number in a red ring is a maximum speed limit, and you must not go faster than it (rule 124). The larger sign marks the start of the limit.

On roads with street lights (other than motorways) a 30 mph limit applies unless signs show otherwise, and in Wales that default is 20 mph. That is why Know your traffic signs says 30 mph repeater signs are used only on roads with no street lighting.

Where you see it

At the start of a 30 mph limit, often where a road enters a town or village. A speed limit sign may be combined with a town or village boundary sign at a village gateway (Know your traffic signs).

A common mistake

Treating 30 mph as the speed to aim for. Rule 125 says the limit is the absolute maximum and does not mean it is safe to drive at that speed in every condition.

Quick quiz

You are on a road in England with street lights and no speed limit signs. What limit normally applies?

  1. 20 mph
  2. 30 mph
  3. 40 mph
Show answer

B. 30 mph. Rule 124: 30 mph generally applies on roads with street lights, unless signs show otherwise. In Wales the default is 20 mph. Source: The Highway Code, rule 124, GOV.UK; The Highway Code, rule 125, GOV.UK; Know your traffic signs: speed limit signs, GOV.UK; Know your traffic signs: information signs, GOV.UK; The Highway Code: traffic signs, GOV.UK; Traffic sign images, Department for Transport, GOV.UK

Compare with

Next in regulatory signs: Minimum speed limit sign. See all regulatory signs or the full road signs list.

Want to test someone else? Play a road-sign quiz with friends and family.

Sources

  1. The Highway Code, rule 124, GOV.UK
  2. The Highway Code, rule 125, GOV.UK
  3. Know your traffic signs: speed limit signs, GOV.UK
  4. Know your traffic signs: information signs, GOV.UK
  5. The Highway Code: traffic signs, GOV.UK
  6. Traffic sign images, Department for Transport, GOV.UK

Contains public sector information licensed under the Open Government Licence v3.0. Traffic sign images are Crown copyright, from the Department for Transport. Sources and image credits.