New report reveals dramatic improvements in London’s air quality since 2016

• Millions more Londoners breathing cleaner air thanks to Mayor’s action to tackle air pollution 
• Annual concentrations of roadside nitrogen dioxide (NO2) were much higher in London than the rest of the UK in 2016 but almost halved in London between 2016 and 2023—compared to 35 per cent across rest of England
• Preliminary figures indicate London’s annual NO₂ levels were lowest on record in 2023 – lower even than first year of COVID-19 lockdowns
• Mayor and TfL invest £5.3 million in 17 ambitious borough-led projects to further reduce pollution and protect public health through Mayor’s Air Quality Fund

London’s air quality has improved much faster and more dramatically than the rest of the UK thanks to the actions of the Mayor of London, Sadiq Khan, according to a new report published today. Annual roadside NO₂ concentrations across the capital have been nearly halved (49 per cent) between 2016 and 2023, while preliminary figures indicate London NO₂ levels were the lowest on record in 2023 – lower even than during the first year of COVID-19 lockdowns.

The Greater London Authority (GLA) report which summarises the impact of the Mayor’s air quality policies since 2016 found that: 

• Average concentrations of nitrogen dioxide (NO₂) were much higher in London than the rest of the UK in 2016 – yet have fallen much more steeply in the capital compared to the rest of the country. 
• Annual roadside NO₂ concentrations in London dropped by nearly half (49 per cent) between 2016 and 2023, despite the population increasing by more than a million, compared to just 35 per cent in the rest of England. Concentrations decreased by 39 per cent in Scotland, 31 per cent in Wales, and 27 per cent in Northern Ireland during the same period. 
• Air pollution has been reduced London-wide, with concentrations decreasing by 65 per cent in central London, 53 per cent in inner London, and 45 per cent in outer London since 2016.
• This shows that the Mayor's policies have driven London's air quality to improve faster than the rest of the UK, by accelerating the uptake of cleaner vehicles and reducing air pollution beyond what would have otherwise happened.

Preliminary figures also indicate that London-average annual mean concentrations of NO₂dropped to the lowest levels ever recorded in 2023 – lower even than during the first year of COVID-19 pandemic lockdowns.² 2023 was also the first year on record where annual mean particulate matter (PM_2.5) concentrations did not exceed the latest interim World Health Organization (WHO) target across London’s active air quality monitoring sites.³  

London has also made significant progress towards reaching the UK’s legal air pollution limits: 

• The number of air quality monitoring sites in London exceeding the UK’s annual legal limit for NO₂ decreased from 56 sites in 2016 to just five in 2023.
• There has been a 99 per cent reduction in the number of hours when NO₂ concentrations exceeded the UK’s hourly limit since 2016 – dropping from 4,130 hours in 2016, to just 22 hours in 2023.
• London’s air quality is now on track to meet UK legal limits by next year – 184 years earlier than previously projected.⁴
• Despite this progress, air pollution levels in London will continue to exceed WHO clean air guidelines in 2025 and 2030. 

In response, the Mayor and Transport for London (TfL) have announced that 17 borough-led projects have been selected to receive a share of £5.3 million in funding to further reduce air pollution, protect public health, and make London a cleaner, greener, and healthier city for everyone.

Boroughs will partner together to tackle NO₂ and PM_2.5, such as a project by Camden, Hackney, and Newham to reduce emissions from canal and river boats. Other projects include a pan-London initiative to reduce idling by commercial vehicles, and a Lewisham project to trial innovative road vents which aim to draw in and filter vehicle exhaust outside schools.

The funding is part of the Mayor’s £27 million Air Quality Fund, which has been matched by more than £20 million in funding and resources from the boroughs and their partners. This has already helped to introduce 25 new clean air routes, support 5,300 businesses to reduce their emissions, and create more than 3,000 square meters of new green space. 

The Mayor of London, Sadiq Khan, said: “Every Londoner should be proud of the remarkable progress we’ve made in improving our air quality since 2016. Together, we’ve cut roadside nitrogen dioxide pollution in half and achieved the lowest annual levels on record. London is leading the way, cleaning up our air at a much faster rate than the rest of the UK. Clean air matters for so many reasons - helping to increase children's life expectancy, reduce hospital admissions for asthma and serious lung conditions, and enable people to lead longer, healthier lives. 

“However, there is still more work to do. Air pollution levels are still damaging Londoners’ health.  That’s why, in addition to world-leading action such as cleaning up our bus and taxi fleets, I’m investing a further £5.3 million in 17 borough-led projects to improve London’s air quality in local communities and build a cleaner, greener, and healthier city for everyone.” 

Shirley Rodrigues, Deputy Mayor for Environment and Energy, said: “It’s incredible to see the progress we’ve made improving London’s air quality since 2016 and I’m very proud that we’ve achieved the lowest annual nitrogen dioxide levels seen on record, with London’s progress continuing to lead the rest of the country. But we cannot be complacent. That’s why we are continuing to invest millions in projects to tackle pollution in communities across the capital, to enable even more Londoners to breathe cleaner air.”

Christina Calderato, Director of Transport Strategy and Policy and TfL, said: “This report shows that the steps the Mayor is taking to clean up London’s toxic air are working and we are pleased to see that measures we’re delivering such as the London-wide Ultra Low Emission Zone, the growing numbers of greener buses and zero emission capable taxis are playing a vital role in ensuring we can all breathe cleaner air. More walking and cycling routes are helping provide more sustainable ways to get around the city and also contribute to a healthier society.

“Pollution is still a significant issue at both a local and national level. In the London we are working with local councils to find innovative ways to create a cleaner, greener city for all. This latest round of funding aims to enable a number of positive changes in people’s neighbourhoods, including greener deliveries, better air quality outside of schools and a project to help make the film industry more environmentally friendly.”

The new funding complements the Mayor’s other ambitious air quality achievements, including: 

• Introducing the world’s first 24-hour Ultra Low Emission Zone (ULEZ) in 2019 and expanding it London-wide in 2023 to create the world’s largest clean air zone of its kind, with 95 percent of vehicles seen driving in London on an average day now compliant with the strict ULEZ emission standards, and £271m provided since 2019 to support Londoners to scrap or retrofit their non-compliant vehicles and transition to cleaner, greener alternatives.
• Improving TfL’s bus fleet, including upgrading the entire TfL bus fleet to meet or exceed ULEZ emissions standards and delivering over 1,300 electric buses to create the largest zero-emission bus fleet in western Europe.
• Supporting the delivery of nearly 19,000 electric vehicle charge points – over one third of the UK’s total – enabling Londoners to adopt electric vehicles at a far faster rate than the rest of the UK.
• Tightening the standards for London’s Non-Road Mobile Machinery (NRMM) Low Emission Zone (LEZ) to tackle the emissions produced by construction site machinery like excavators, diggers, bulldozers, and other heavy-duty equipment.
• Acting to reduce air pollution at schools and nurseries, auditing air quality at 50 schools and 20 nurseries, introducing the London Schools Pollution Helpdesk to provide free support and guidance to help improve air quality, and announcing plans to install PM_2.5 filters in every classroom of 200 schools.
• Launching Breathe London, a comprehensive network of over 400 hyper-local, accurate and reliable air quality sensors, helping local community groups to monitor and manage their exposure to air pollution across London.
• Introducing a pioneering air quality alerts system to notify Londoners during the worst episodes of air pollution, delivering alerts directly to boroughs, schools, GPs, and emergency departments, along with displaying alerts on bus stop countdown, Underground, and roadside signs.
• Requiring all new developments in London to not contribute to air pollution and major developers to consider their impact on air quality from the earliest design stages through new, world-leading Air Quality Neutral and Air Quality Positive guidelines.

Rosamund Adoo-Kissi-Debrah CBE, Founder of the Ella Roberta Foundation, said: "The Coroner (following Ella’s death) recommended that the Mayor take action to clean up London’s air to prevent future deaths from air pollution in the capital.  I am pleased the Mayor has taken the Coroner’s inquest seriously and I know Ella would be pleased that despite her indescribable suffering, she triggered change to happen.  Her legacy is a cleaner London and safer air for other children to breathe.

“Of course, we still have a long way to go to truly clean up London’s air, but it fills me with hope when policy makers listen to advice and are committed to protecting people’s health.  I hope the work will continue in Ella’s memory so that all Londoner’s get to breathe clean, safe air in the future."

Dr Maria Neira, Director of the Department of Environment, Climate Change and Health at the World Health Organization (WHO) said: “Breathing clean air is a fundamental human right. London's commitment to implementing WHO air quality guidelines not only elevates the health and well-being of its people but sets a powerful example for global cities worldwide. The WHO air quality guidelines serve towards healthier lives for all, safeguarding our well-being today and for generations to come. In the collective pursuit of these goals, we strongly encourage London to continue every effort to improve its air quality.”

Jemima Hartshorn, Co-Founder of Mums for Lungs said: “As parents and carers we are so relieved that London’s air has significantly improved over the past eight years. It hasn’t been easy, but the Mayor and Londoners have risen to the public health crisis and reduced air pollution. Children are breathing easier. But there is a lot more to do including reducing diesel transport and wood burning, until air pollution no longer makes children sick.”

Hirra Khan Adeogun, co-director of climate charity Possible, said: “It’s encouraging to see that air quality in London is improving. Toxic air and excessive car use is destroying our health and harming the planet.

“While we are now on track to meet legal limits of air pollution, we still need to go further and faster to protect all Londoners, especially vulnerable children. In this election year, we need to see politicians of all parties taking their role as climate leaders seriously, supporting Londoners to get about in cleaner, greener ways.”

Henry Gregg, Director of External Affairs at Asthma + Lung UK said: “London is leading the fight against toxic air by implementing ambitious air quality policies that put the health of Londoners first. Toxic air is a public health emergency which affects us all, and especially the lives of the 585,000 people in Greater London who have asthma and COPD*. Air pollution can worsen the symptoms of people with existing lung conditions, such as breathlessness, wheezing and coughing, and potentially lead to life-threating asthma attacks or serious flare-ups.

“Despite some improvements to the public transport network in London, more action is still needed in many toxic air hotspots, especially in outer boroughs. Targeted investment is urgently needed to make public transport, walking and cycling more reliable, accessible and affordable for all Londoners. Only then can we truly apply the emergency brake on toxic air and save more lives.”