TfL Ref: FOI-1033-2425

Thank you for your request which we received on 28 June 2024, asking for information about our 20mph speed restriction scheme.

Your request has been considered in accordance with the requirements of the Freedom of Information Act and our information access policy.  I can confirm that we hold the information you require.

Collision data from around the world shows that the speed at which people are driving or riding is the single most important factor in whether a collision takes place and how severely people are injured. Around half of the 2022 fatal collisions in London (48 out of 99) reported speed as a contributory factor.

TfL’s Lowering Speed Limits programme was launched in July 2018 as part of our Vision Zero Action Plan and set a target to introduce a new 20mph speed limit in central London by May 2020 and on a further 140km of TfL roads by May 2024.  In February 2023, we published indicative findings from analysis of the pre- and post-implementation personal injury collision records. This shows a significant reduction in the number of collisions since the 20mph speed limit was introduced on our roads within the central London Congestion Charging Zone, including:

•           25% reduction in collisions of all severities
•           24% reduction in collisions resulting in fatal or serious injury

These results should be seen in the context of a London-wide reduction in collisions resulting in death or serious injury of around 10% over the same period.

For access to the pre- and post-implementation data used in the analysis above, please visit:  https://tfl.gov.uk/corporate/safety-and-security/road-safety/safe-speeds

If this is not the information you are looking for, or if you are unable to access it for any reason, please do not hesitate to contact me.

Please see the attached information sheet for details of your right to appeal as well as information on copyright and what to do if you would like to re-use any of the information we have disclosed. 

Yours sincerely

Eva Hextall 

FOI Case Management Team

General Counsel

Transport for London