When Wales introduced the default 20mph speed limit on many residential and built-up roads in September 2023, it quickly became one of the most debated changes to road law in recent years.

Many motorists questioned whether the lower speed limit would make roads safer, while others felt it would simply slow journeys without reducing accidents.

So, what does the evidence tell us?

What do the latest figures show?

Based on the latest published statistics, road traffic accidents have not increased on roads affected by the default 20mph limit. In fact, early data suggests the opposite.

Figures published by the Welsh Government and analysed by the Senedd show that casualties on 20mph and 30mph roads fell by almost 24% between the period before the speed limit change and the end of 2024. During the same period roads with higher speed limits experienced a slight increase in casualties.

Earlier monitoring reports also found that:-

• Collisions on 20mph and 30mph roads reduced significantly.
• Around 100 fewer people were killed or seriously injured during the first year following the introduction of the default speed limit.
• The greatest improvements were seen on residential roads where pedestrians, cyclists and motorists share the same space.

Why would reducing speed make such a difference?

The principle is relatively straightforward. At lower speeds, drivers generally have:

• More time to react.
• Shorter stopping distances.
• Greater ability to avoid collisions altogether.

Where collisions do occur, the severity of injuries is often reduced because the force of impact is significantly lower. For vulnerable road users such as children, elderly pedestrians and cyclists, even a small reduction in speed can make a substantial difference to the outcome of an accident.

Does that mean the debate is over?

Not at all. The 20mph limit remains controversial.

Many drivers argue that blanket 20mph limits are unnecessary on some roads and that journey times have increased, others have raised concerns about enforcement and inconsistent signage.

However, when looking purely at the available collision data, there is currently no evidence that the introduction of the default 20mph limit has led to an increase in road traffic accidents. Instead, the available statistics point towards a reduction in collisions and casualties on affected roads.

If you have been injured in a road traffic accident

Even with improved road safety measure accidents still happen every day.

If you have been injured as a driver, passenger, cyclist or pedestrian, you may be entitled to claim compensation if the accident was caused by somebody else.

Seeking legal advice early can help preserve important evidence, establish liability and ensure you receive the support and compensation you may be entitled to.

If you would like to discuss a road traffic accident claim please call 01492 685462 or email zoey.smith@baineslaw.uk.