Speed limit signs

Freedom of Information (FOI) Act request ref: 01/FIN/25/3035

Version Date: 07/04/2025

Could you please tell me why you do not have to (by law) put up speed limit signs on a residentail area? (even on a dual carriageway)

I was told by Dorset Road Safe by telephone that if a speed limit was reduced from a 40mph to a 30mph zone that you do not have to put up any signage as it is residential, is this true, if so why is this please?

The Head of Road Safety has provided the following information.

From the Department for Transport:

In areas of street lighting (other than on motorways), a speed limit of 30 mph applies unless signs show otherwise. In Wales, this limit is 20 mph.

Repeater signs for a 30 mph limit are used only on roads with no street lighting.