How fast drivers are going on Wales' 20mph roads

New data reveals the average speed that drivers in Wales are travelling at.

Fresh data reveals the driving speeds on Wales' 20mph roads, nearly a year and a half after the speed limit change was implemented. The new default limit was rolled out across the majority of previously 30mph roads in Wales in September 2023.

Transport for Wales has been tracking speeds at 43 locations in 10 different regions across Wales since the summer of 2023, with approximately seven million vehicle journeys recorded during each monitoring period. The study examined several statistics, including the percentage of drivers travelling at or under 24mph on roads that transitioned from 30mph to 20mph and the weighted average speed of all drivers.

In the summer of 2023 - before the new limit was introduced - 20.8% of drivers were clocked at or below 24mph. During this same period, around 37% of drivers were exceeding 30mph, with 10.4% of those reaching 35mph or higher.

While the weighted average speed of all drivers for that period was 28.7mph.

The same monitoring process was repeated in the winter of 2023/24 and the summer of 2024, and again for the winter of 2024/25. The most recent data, from January 2025, comes nearly 18 months after the speed limit change.

This latest data indicates that 54% of drivers at the monitored sites were driving at or below 24mph - an increase of about 33% compared to the summer 2023 figure.

The percentage of drivers exceeding 30mph on these roads was 15.2%, with 3.9% of those hitting 35mph or above - a significant decrease from the 2023 figure

The average speed of all drivers was recorded at 24.9mph, approximately 4mph slower than in the summer of 2023.