Symbol on road signs informing drivers of the Ultra Low Emission Zone
Symbol on road signs informing drivers of the Ultra Low Emission Zone
Boundary of the ULEZ for 2021-2023

The Ultra Low Emission Zone (ULEZ) is an area in London, England where a fee is charged for driving the most polluting vehicles.

Plans were laid out under Mayor Boris Johnson and introduced by Sadiq Khan in April 2019 in Central London, covering the same area as the congestion charge. In the four months following its introduction there was a 20% reduction in emissions[clarification needed] in Central London and the number of the worst polluting vehicles dropped from 35,600 to 23,000.[1][2]

However, some research suggests the ULEZ caused only small improvements to air quality.[3][4]

In August 2023 it will extend to cover all of Greater London.

Current charging scheme

The £12.50 charge applies 24 hours a day every day of the year, and is based on European emission standards:

History and planned extension

Sign warning drivers that they are about to enter the Ultra Low Emission Zone and Congestion Charging Zone
Sign warning drivers that they are about to enter the Ultra Low Emission Zone and Congestion Charging Zone

Plans for an ultra–low emission zone were under consideration since 2014 under Mayor Boris Johnson.[5] In February 2017, Mayor Sadiq Khan announced plans to expand the Ultra Low Emission Zone in April 2019 beyond Central London, one year ahead of schedule. Drivers do not pay both the ULEZ and the previous £10 T-charge, but they are still subject to the London Congestion Charge.[6][7] The money raised from the ULEZ is invested in the transport network and improving air quality in London.[8]

October 2021 expansion

The zone was expanded to cover the Inner London area inside the North and South Circular roads on 25 October 2021 so that it covers an area containing 3.8 million people.[9][10] Around a million vehicles a day drive in the expanded zone, but Transport for London (TfL) estimated that 87% already complied with the emissions rules, meaning nearly 140,000 vehicles would have to be replaced or pay the charge, including 100,000 cars, 35,000 vans and 3,000 lorries.[11][12]

There was a scrappage scheme to help those on income support or disability benefit to get rid of their old vehicle. This was used to scrap at least 12,000 vehicles. The Mayor said on 14 October 2021 that there was less than £2 million left in the £61m fund.[13]

A month into the expansion, TfL said that the proportion of compliant vehicles had risen from 87% to 92%, and the number of the most polluting vehicles had fallen by over a third (from 127,000 to 80,000 on weekdays). They also said that 94% of cars complied compared to 78% of vans.[14] Six months after the expansion, TfL estimated that NOx in Inner London was 20% lower than it would have been without the expansion and found that 95% of cars and 83% of vans now met the standard.[15]

August 2023 expansion

The zone will be expanded in August 2023 to cover all of Greater London. TfL estimates 20,000 to 40,000 vehicles will be taken off the road due to the expansion. Khan said "This is also a matter of social justice – with air pollution hitting the poorest communities the hardest. Nearly half of Londoners don’t own a car, but they are disproportionally feeling the damaging consequences polluting vehicles are causing."[16]

Critics argue the expansion disproportionately impacts poorer Londoners, who are more likely to own an older, non-compliant vehicle that will be subject to the daily charge.[17][18]

TfL found that 60% of those who responded to its public consultation into the expansion plans were opposed, as well as 70% of outer London residents and 80% of outer London workers.[19][20][21]


Effect on air pollution

The zone was introduced on 8 April 2019 and led to a 20% reduction in emissions[clarification needed] by July 2019.[22][2]

From 2016 to 2020, NO2 pollution dropped five times as quickly in Central London as it did in the rest of the UK.[23]

However, a study from Imperial College London found the ULEZ caused only small improvements to air quality after it was implemented.[3][4] It stated that there has been a longer-term downward trend in London’s air pollution levels and argued that the ULEZ on its own is not an effective strategy for improving air quality.[3]

NOx emissions from road transport in Greater London (GLA boundary) from 2013 to 2019[24]
NOx emissions from road transport in Greater London (GLA boundary) from 2013 to 2019[24]

Effect on vehicle numbers

The number of the worst polluting vehicles entering the zone each day dropped from 35,578, in March 2019, to 26,195 in April of the same year, after the charge was introduced.[25] The number further dropped to 23,054 in July 2019.[1] The proportion of vehicles which complied with the standards rose from 61% in March 2019 to 74% in September 2019.[26] It further rose to 85% in December 2020, including 90% for cars, and the number of non-compliant vehicles dropped to around 12,000 (of which 4,000 were exempt from the charges).[27][28]

The total number of vehicles entering Central London each day also dropped from over 102,000 in February 2017 to 89,000 in April 2019.[29]


The Ultra Low Emission Zone has been described as one of the most radical anti-pollution policies in the world.[30] A poll in April 2019 by YouGov found that 72% of Londoners supported using emissions charging to tackle both air pollution and congestion.[31] However, the Federation of Small Businesses said that many small firms were "very worried about the future of their businesses" as a result of the "additional cost burden".[22]


Residents of the zone did not pay the charge until October 2021 as long as they were registered for the residents' Congestion Charge discount and met the T-charge standards. Vehicles in the "disabled" tax class are exempt from the charge, as are London-licensed taxis, private hire vehicles which are wheelchair accessible and historic vehicles (over 40 years old). There are also exemptions for agricultural vehicles, military vehicles, certain types of mobile cranes and non-road going vehicles which are allowed to drive on the highway (e.g. excavators).[32]

See also


  1. ^ a b "Central London Ultra Low Emission Zone - Four month report" (PDF).
  2. ^ a b Bayley, Sian (23 July 2019). "London pollution: High levels detected by 40% of capital's air quality". Evening Standard.
  3. ^ a b c Ma, Liang; Graham, Daniel J; Stettler, Marc E J (1 December 2021). "Has the ultra low emission zone in London improved air quality?". Environmental Research Letters. 16 (12): 124001. doi:10.1088/1748-9326/ac30c1. ISSN 1748-9326. S2CID 244169411.
  4. ^ a b "London's Ultra Low Emission Zone resulted in only 'marginal' air quality improvements shortly after it was introduced". Sky News. Retrieved 9 December 2022.
  5. ^ Harvey, Fiona (29 July 2014). "Diesel drivers may face higher costs in pollution battle". The Guardian. Retrieved 29 July 2014.
  6. ^ Mason, Rowena (17 February 2017). "London to introduce £10 vehicle pollution charge, says Sadiq Khan". The Guardian. Retrieved 23 February 2017.
  7. ^ de Reytas-Tamura, Kimiko (17 February 2017). "A Push for Diesel Leaves London Gasping Amid Record Pollution". The New York Times. Retrieved 23 February 2017.
  8. ^ "World's first 24 hour Ultra Low Emission Zone starts in London". London City Hall. 8 April 2019.
  9. ^ Roberts, Gareth (3 November 2017). "London Mayor confirms Ultra-Low Emission Zone will start in 2019". Fleet News. Archived from the original on 25 July 2019. Retrieved 24 July 2019.
  10. ^ Edwards, Tom (5 April 2019). "ULEZ: The politics of London's air pollution". BBC News.
  11. ^ Lydall, Ross (14 May 2021). "Khan presses ahead with Ulez expansion set to hit 140,000 drivers". Evening Standard. Retrieved 25 October 2021.
  12. ^ "Ultra-low emission zone comes into force in central London". ITV News. 7 April 2019. Retrieved 25 October 2021.
  13. ^ Lydall, Ross (15 October 2021). "London's ULEZ scrappage scheme running out of cash". Evening Standard. Retrieved 25 October 2021.
  14. ^ Lydall, Ross (10 December 2021). "Ulez expansion revealed to have cut 'dirty' vehicles by over a third". Evening Standard. Retrieved 8 April 2023.
  15. ^ "Millions of Londoners breathing cleaner air thanks to ULEZ expansion". 19 July 2022.
  16. ^ Lydall, Ross (8 March 2022). "ULEZ to expand across all of Greater London". Evening Standard. Retrieved 8 April 2023.
  17. ^ Clark, Ross (25 November 2022). "Sadiq Khan's Ulez expansion punishes the poorest". The Spectator. Retrieved 9 December 2022.
  18. ^ "Letters: Sadiq Khan's war on emissions penalises those who can least afford it". The Telegraph. 2 December 2022. ISSN 0307-1235. Retrieved 9 December 2022.
  19. ^ "ULEZ: Ultra Low Emissions Zone to cover all of London". BBC News. 25 November 2022. Retrieved 9 December 2022.
  20. ^ Gill, Oliver; Holl-Allen, Genevieve (25 November 2022). "Sadiq Khan plans London toll roads as electric car use rises". The Telegraph. ISSN 0307-1235. Retrieved 9 December 2022.
  21. ^ "Improving air quality and Londoners' health, tackling climate change and reducing congestion". Have Your Say Transport for London. Retrieved 9 December 2022.
  22. ^ a b "ULEZ: New pollution charge begins in London". BBC News. 8 April 2019.
  23. ^ "5 times greater reduction in NO2 in London than rest of the country". London City Hall. 7 August 2020.
  24. ^ "Diesel cars pollutes more than trucks & lorries combined". Clean Cities. 2 March 2022. Archived from the original on 22 May 2022.
  25. ^ Taylor, Matthew (16 May 2019). "ULEZ cuts number of worst polluting cars in central London". The Guardian.
  26. ^ "Central London Ultra Low Emission Zone - Six Month Report" (PDF).
  27. ^ "New tighter Low Emission Zone standards for HGVS introduced in London". March 2021.
  28. ^ "ULEZ Online Fact Sheet" (PDF). Retrieved 25 October 2021.
  29. ^ "First month of Mayor's ULEZ sees 74 per cent of vehicles comply". London City Hall. 16 May 2019.
  30. ^ Edwards, Tom. "ULEZ: The most radical plan you've never heard of". BBC News Website. BBC. Retrieved 26 March 2019.
  31. ^ Taylor, Matthew; Sedghi, Amy (8 April 2019). "Londoners support charging 'dirty' drivers, says air pollution study". The Guardian – via
  32. ^ "Discounts and exemptions". Transport for London.