Reducing the default speed limit on built-up roads in Wales to 20mph has brought multiple benefits. Lower speeds have led to 678 (28%) fewer casualties in the twelve months after the national speed limit change with the previous year, including 10 fewer deaths.

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 default speed limit on built-up roads to 20mph has seen multiple benefits for people in Wales: lower speeds, fewer casualties and reduced insurance premiums.  The new 20mph speed limit has seen 678 (28%) fewer casualties in the twelve months since September 2023[1] compared with the previous year.  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[2].

While it’s still early days, nine months of data indicates that the positive impact of 20mph in Wales is more than a statistical ‘blip’:

• The drop in casualties of 28% on 20 / 30mph roads compares with a 2% increase on roads with higher speed limits (Fig. 1).
• Data is consistent across all quarters: the drop in casualties on 20/40mph roads ranged from 21% to 35%. On 40mph+ roads, the range was +7% to -4% (Fig. 2).
• The long-term trend shows a marked downturn after September 2023 on 20/30mph roads but not on 40mph+ roads (Fig. 3). The drop in casualties on 20/30mph roads was nearly 3x the biggest %age fall seen in the 21st Century, excluding the COVID period.
• Trends confirmed by individual Local Authority (Fig. 4):
  1. 20 out of 22 LAs saw fewer casualties on 20 / 30mph roads
  2. On 40mph+ roads, 11 LAs had fewer casualties and 11 had more
• Casualty reductions of 28% are in line with those predicted by lower mean speeds (2.4mph[3] overall and 4.3mph on faster roads[4]).

Vehicle damage claims in Q4 2023 from esure are 20% lower than expected.[5]

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[1] StatsWales website

[2] https://tinyurl.com/54yjmabm

[3] https://agilysis.co.uk/2024/01/22/wales-20mph-3months-on/

[4] https://tfw.wales/about-us/transparency/publications/default-20mph-speed-limit

[5] https://www.20splenty.org/welsh_accidental_damage_claims

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Fig. 1 change in casualties by severity 20/30 mph roads vs. 40mph+ (table and chart)

Fig. 2 Quarterly comparison 20/30 mph roads vs. 40mph+ (all casualties)

Fig. 3 long term trend in casualties on 20/30 mph roads vs. 40mph+ (all casualties)

Fig. 4 casualties by Local Authority (20/30 mph vs. 40mph+) (1st SIX months)