Lowering Speed Limits Programme

The Mayor and Transport for London (TfL) are committed to Vision Zero, eliminating death and serious injury from London’s roads. The Vision Zero Action Plan sets out our ambition and next steps to achieve this. It details our plans to reduce road danger, including proposals to implement safer speeds on the roads we operate and manage across London.

What we are doing

Our Vision Zero Action Plan sets out our aims to lower the speed limit by 10mph in selected locations on the Transport for London Road Network (TLRN). TfL manages the TLRN which is made up of London’s most strategic roads, accounting for roughly 5% of London’s roads. The remaining 95% of London’s roads are managed by local authorities.

Currently 267km of the TLRN is subject to a 20mph speed limit and over half of London's roads now have a 20mph speed limit. It's the policy of two thirds of London local authorities to apply this limit to most of their roads. The Mayor has asked us to continue the programme of reducing speeds on the TLRN as there are more locations where we can reduce speeds to reduce collisions and casualties across London.

Works are starting for Phase 3 of our Lowering Speed Limits programme in early 2026. This phase involves reducing speed limits on roads on the TLRN in nine more locations.

• A23 Thornton Road: Thornton Heath Pond to, and including, Lombard roundabout
• A24 Stonecot Hill: Gander Green Lane to Sutton Common Road
• A1 Archway Road: 20mph from Bakers Lane to Archway with a small section of 30mph on Aylmer Road
• A214 Trinity Road/Tooting Bec Road: Windmill Road to the borough boundary with the London Borough of Lambeth
• A10 The Roundway/Bruce Grove: The Avenue to Waltehof Gardens
• A2213 Kidbrooke Park Road: Peglar Square to Eltham Road
• A306 Roehampton Lane: Upper Richmond Road to Kingston Road
• A316 Corridor: 30mph from St Margarets Roundabout to Old Deer Park
• A312 Church Road: White Hart Roundabout to Western Avenue/Target Roundabout

We are committed to improving transport in London by making it safe and reliable. All of our plans have been designed with this in mind. Please view our Equalities Statement for more information.

Our work consists of installing new traffic signing and relining the carriageway. The majority of works will be carried out under ‘mobile works’ with minimal impact to road users and pedestrians. In some cases, as a last resort, carriageway and footway closures will be utilised with diversions in place.

Why we are lowering speeds

Collision data from around the world is very clear. It shows the faster a vehicle is travelling, the more likely a collision will occur because the driver has less time to react, stop or avoid the collision and the more severe an injury resulting from the collision will be.

We recently published a study which examines the impact of over 150 20mph schemes on borough roads in London between 1989 and 2013. Our report – the first of its scale in London – comprehensively demonstrates that 20mph schemes have had a significant positive impact on reducing the number of people killed or seriously injured (KSI) on our roads. It shows that on borough roads where 20mph speed limits were introduced, there was a 34% reduction in the number of people killed or seriously injured (from 395 to 260), compared against the background trend of a 15% fall.

The effectiveness of the Lowering Speed Limits programme on the TLRN so far

Phase 1

Data collected from 1 May 2020 to 30 June 2022 were compared to a similar seasonally-matched period before 20mph speed limits were implemented in the central London Congestion Charging Zone in 2020. The number of collisions fell 25% (from 405 to 304), and collisions resulting in death or serious injury fell 24% (from 94 to 71).

The London-wide reduction in collisions resulting in death or serious injury fell around 10% over the same period.

Collision data for the whole of London is provided in CSV extracts on our website every year. We provide more information on our calculations and methodology at the bottom of our Safe Speeds webpage. A detailed report has been commissioned which is due to be published later in 2026.

Phase 2

Detailed analysis will be published after 3 years’ worth of collision data becomes available.

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