28% fewer casualties in 1st 12 months of 20mph in Wales

The default speed limit of 20mph on built-up roads in Wales has brought multiple benefits. Lower speeds have led to 630 (26%) fewer casualties in the twelve months after the national speed limit change compared with the previous year, including 80 fewer fatal or serious injuries.

Lower than expected vehicle damage claims has enabled esure Insurance Group to reduce its premiums for Welsh drivers and esure is now committed to reducing policy prices for customers within 3 months of identifying a new 20mph area in the rest of the UK.

Reducing the 20mph default speed limit on built-up roads in Wales has led to a reduction in casualties on those roads of 630 (26%) in the first twelve months[1]. Excluding roads where the speed limit was unchanged, this is a c. 37% reduction. In other words, but for the introduction of 20mph, casualties would have been 60% higher on those urban/village roads that had been changed!

Lower than expected vehicle damage claims enabled esure Insurance Group to reduce premiums for Welsh drivers. The firm is now committed to reducing policy prices for customers within 3 months of identifying a new 20mph area in the rest of the UK[2].

First year data indicates that the positive impact of 20mph in Wales is more than a statistical ‘blip’:

The fall in casualties of 26% on 20/30mph roads compares with an INCREASE of 4% on roads with higher speed limits (Fig. 1).

Data is consistent across all four quarters: the drop in casualties on 20/30mph roads ranged from 18% to 32%. On 40mph+ roads, the range was +10% to -3% (Fig. 2).

The marked downturn after September 2023 on 20/30mph roads – nearly 3x the previous largest drop, excluding COVID years – was not seen on other Welsh roads (Fig. 3).

All four police forces saw casualty reductions on 20/30mph roads, ranging from 7% (Gwent) to 46% (North Wales). North Wales also saw the largest %age of speed limit reductions (94% of roads changed from 30mph to 20mph) and 6 Local Authorities in the area witnessed among the largest casualty reductions - ranging up to 59%.

19 out of 22 Local Authorities saw casualty reductions on 20/30mph roads; casualty changes on other roads ranged from a decrease of 24% to an increase of 64% (Fig. 5).