Wales 20mph Impact Analysis

Organisation: Agilysis

Date of Publication: September 2023

Uploaded to Knowledge Centre: 27 September 2023

This report provides independent analysis of vehicle speeds in the first week after the implementation of 20mph speed limits in Wales.

The analysis shows that traffic speeds on urban roads in Wales fell by 2.9mph since the introduction of the country’s default 20mph speed limit.

Carried out by Agilysis, the analysis used traffic information along main routes in 10 towns and cities, totalling 261 miles in length, in the period one week before and one week after the switch.

Access the report via the Agilysis website: