Data from City Hall has found that ULEZ has led to a hefty fall in emissions around the city, including a 46% drop in central London.

Ultra Low Emission Zones (ULEZ) were first introduced in the capital in 2019, then underwent a considerable expansion in 2021. There are even plans to stretch the zones out to cover all of Greater London in the future, with all 32 London boroughs poised to fall under the boundaries later this year.

But has the rollout of ULEZ actually made a difference to the levels of air pollution in London? The data would suggest it has, in a significant way.

A report from City Hall has found that the impact of ULEZ has been a great one, with pollution levels 46% lower in central London and 21% lower around inner London than what they would have been if they had not been introduced.

ULEZ means that drivers with vehicles that don’t meet low emission standards are charged £12.50 per day for entering roads within the North and South Circulars in the city. Mayor Sadiq Khan hopes to extend this across the whole city, though it has been met with opposition.

Emissions within the expanded ULEZ zone, since October 2021, has led to a 26% drop in harmful emissions, including rates of Carbon Dioxide and Nitrous Oxide. It was also found the 74,000 fewer polluting vehicles are driving within the zone since the expansion in 2021.

Since the introduction of ULEZ, it is estimated that more than four million people breathe markedly cleaner air, a number that encompasses children at 1,362 schools. Levels of Nitrous Oxide, for example, have fallen by 23% (13,500 tonnes) since 2019.

Speaking on ULEZ, Mayor Sadiq Khan said: “The evidence from this landmark report is clear – the ULEZ works. This is beyond dispute. It has already reduced toxic air pollution by almost half in central London and by over a fifth in inner London, transforming the quality of air for four million Londoners.

“But there’s still more to do. Toxic air is a matter of life and death, with around 4,000 deaths in London attributed to air pollution in 2019. It’s also stunting the growth of children’s lungs and causing people to develop life-changing illnesses, such as cancer, lung disease, dementia and asthma.

“With the majority of deaths attributable to air pollution in outer London, it’s vital that we expand the ULEZ London-wide. As Mayor, I simply won’t accept that the five million people in outer London shouldn’t be able to benefit from the same life-saving health impacts that ULEZ has already brought to the rest of our city. Everyone has the right to breathe clean air.”

Plans are for ULEZ to expand to all 32 London boroughs in August 2023. You can read the City Hall findings here.