London's 20-MPH Speed Limit Reduced Traffic Fatalities by 25 Percent

Photo: David Cliff/NurPhoto (Getty Images)

Early during the COVID-19 pandemic, Transport for London (TfL) suspended congestion charges in Central London for three months to make traveling easier for frontline workers. Also, in March 2020, TfL lowered the speed limit to 20 mph in the 8.1-square-mile area. The change was made with the hopes of making London’s streets safer. After almost three years, recently released data shows that the roads of the British capital are significantly safer, and other cities are planning to follow London’s lead.

Transport for London released data showing that crashes in the Congestion Charge Zone dropped by 25 percent after the speed limit was reduced from 30 mph to 20. Collisions that seriously injured or killed people also dropped by 25 percent. Incredibly, crashes involving pedestrians are down 63 percent.

Of course, a new speed limit only works if it’s being enforced. The Metropolitan Police Service gave out more than 475,000 speeding tickets throughout 2021 and 2022, a 72-percent increase.

In light of the success, TfL is planning on doubling the size of the 20-mph zone, from the current 68 miles of city streets to a total of 136 miles by 2024. The ultimate goal is to see the city achieve its Vision Zero commitment, eliminating all traffic deaths and serious injuries on London streets by 2041.

Will Norman, London’s Walking & Cycling Commissioner, said in a statement:

“Sadly more than 4,000 people are killed and seriously injured on London’s roads every year. Lowering speeds is one of the most important things we can do to reduce road danger and make it easier and safer for people to walk, cycle and use public transport, creating a safer, greener London for everyone.”

Other cities have noticed the safety improvements in London and are considering similar changes, including America’s largest city. According to Streetsblog, New York State is pursuing legislation that would allow New York City to set speed limits lower than 25 mph. TfL says that a person hit by a vehicle traveling 30 mph is five times more likely to be killed than if the vehicle is traveling at 20 mph. The math is simple in densely populated areas. If traffic moves more slowly, fewer people get injured or killed.