London-wide Ultra Low Emission Zone First Month Report

There is a well-established and ever-growing body of scientific evidence linking exposure to air pollution and a number of adverse health effects across all stages of life, with these effects seen even in relatively low air pollution environments. In 2021, the World Health Organization (WHO) updated its air quality guidelines, recommending more stringent guidelines to protect public health. The updated WHO air quality guidelines are more ambitious than the UK national legal limits and emphasise that no safe level of air pollution exists. 

On the 29 August 2023, to help tackle air pollution in the capital, the Mayor of London expanded the Ultra Low Emission Zone (ULEZ) across all London boroughs. The ULEZ boundary is now the same as the boundary for the Low Emission Zone (LEZ) for heavy vehicles. The London-wide zone measures 1,500km² and covers nine million people, making it the largest zone of its kind in the world.

This report evaluates the impact of the newly expanded scheme in its first month. The initial data shows that the scheme has been highly effective at reducing the proportion and number of older, more polluting vehicles on London’s roads. To fully understand the impact of the London-wide ULEZ it is necessary to account for the fact that many people will have made changes in advance to prepare for the formal start of the scheme, with key dates including the launch of the consultation in May 2022 and the announcement of the Mayor’s decision to proceed with the expansion in November 2022. This has been part of the scheme design from the beginning and is a well understood feature of schemes like the ULEZ.

This report focuses primarily on the “compliance rate” of vehicles travelling in the zone that are subject to the ULEZ standards – that is cars, vans, minibuses, and motorcycles. The compliance rate is the percentage of vehicles detected in the zone that meet the ULEZ standards. The higher the compliance rate the more successful the scheme has been in accelerating the transition to cleaner vehicles.

A larger proportion of vehicles seen driving in London are cleaner. The London-wide compliance rate for vehicles subject to the ULEZ standards during the first month was 95.3 per cent, up from 91.6 per cent in June 2023 and 39 per cent in February 2017 when changes associated with the ULEZ began.

Compliance rates have increased for both cars and vans. 96.4 per cent of cars and 86.2 per cent of vans seen driving in the London-wide ULEZ met the standards in the first month of operation, up from 93 and 80.2 per cent in June 2023 and 44 and 12 per cent in February 2017.

There are fewer older, more polluting cars seen driving in the zone. On an average day, there were 77,000 fewer unique non-compliant vehicles (i.e., individual vehicles detected travelling in the zone at least once) seen detected in the London-wide ULEZ compared to June 2023. This is a 45 per cent reduction in non-compliant vehicles.

There has also been an overall reduction in vehicles seen driving in the zone. On an average day, there were 48,000 fewer unique vehicles driving each day in the London-wide ULEZ compared to June 2023. This is a two per cent reduction, although it will take more time for traffic patterns post launch to fully emerge. Preliminary analysis of traffic flows indicates there have been no notable changes across London or on the London-wide ULEZ boundary. However, it is too early to draw firm conclusions and monitoring will continue in the coming months.

In the expanded outer London area, vehicle compliance has increased by 10 percentage points since the launch of the consultation to expand the ULEZ London-wide. Vehicle compliance in the expanded outer London area is now 95.2 per cent, up from 85.1 per cent in May 2022 when the consultation on proposals to expand the ULEZ London-wide launched, and from 90.9 per cent in June 2023. 

The London-wide ULEZ has closed the compliance gap between outer London and inner and central London. After just one month of the London-wide ULEZ operating, compliance rates for vehicles using London’s roads are now nearly the same across all areas of London for each vehicle type.  Overall vehicle compliance in the expanded outer London area is now 95.2 per cent, compared to 95.9 per cent in inner London the same month.

In outer London, well over nine in ten cars now meet the ULEZ standards. Car compliance in the expanded outer London area is 96.4 per cent, up from 92.4 per cent in June 2023 and 90 per cent in November 2022 when the Mayor announced the decision to expand the ULEZ London-wide. Van compliance in the outer London area was 86.2 per cent, up from 79.5 per cent in June 2023 and 77.8 per cent in November 2022.

High levels of compliance mean only a small proportion of vehicles paid the charge. On an average day, of all ULEZ vehicles seen driving in London, only 2.9 per cent pay the charge, 1.7 per cent are non-chargeable (including those registered for a discount or exemption), and 0.2 per cent are issued with a warning notice or, from 26 September, a penalty charge notice. The rest meet the ULEZ standards.

There is still support available. To support the transition to cleaner vehicles, the Mayor has provided £160 million in funding for a scrappage and retrofit scheme. The scheme provides grants to help Londoners, small businesses and charities prepare for the London-wide expansion. This is in addition to an expanded set of temporary exemptions (“grace periods”) to support disabled people, community transport minibuses, people using wheelchair accessible vehicles, and businesses and charities with brand-new compliant vehicles or a retrofit solution on order. In August 2023, the Mayor and TfL expanded the eligibility of the scrappage scheme, meaning every Londoner with an eligible non-compliant car or motorcycle can apply for up to £2,000 to transition to a ULEZ compliant one.