Accent MR Accent

Gauging consumer reaction to an Ultra Low Emissions Zone for TfL


The Mayor of London had announced his intention to create the world’s first Ultra Low Emissions Zone (ULEZ) in central London with the aim of ensuring all vehicles driving in the centre of London during working hours would be zero or low emission from 2020. The ULEZ aimed to reduce air quality pollutant (NOx/NO2 and PM10) emissions without increasing CO2 emissions. The key objective of the research was to understand how current road users were likely to respond to different permutations of the ULEZ scheme.


The research consisted of both qualitative and quantitative research. Focus groups and business depths were conducted first – to inform the quantitative surveys. The qualitative phase was followed by 1,000 online interviews with car and van drivers and a CATI survey of 200 fleet operators.

The key aim of the quantitative phase was not only to understand how different road users in central London would be likely to respond to the ULEZ scheme but also to gauge how sensitive their responses would be to a range of scheme variations. A Stated Preference technique was employed to achieve this objective.


The ULEZ was introduced by TfL in April 2019 and now operates 24 hours a day, 7 days a week, within the same area of central London as the Congestion Charge. Most vehicles, including cars and vans, need to meet the ULEZ emissions standards or their drivers must pay a daily charge to drive within the zone. From 25 October 2021, the ULEZ is being expanded  to create a single, larger zone that will extend to the North Circular and South Circular Roads.