Clean Air Zones – what are they and where are they?

Designed to improve air quality, these zones are intended address sources of pollution and improve public health.

If you drive a vehicle that exceeds the minimum emission criteria for a CAZ or LEZ, you may have to pay a charge. The rules vary from area to area, which is why it’s important to check your vehicle meets the required emission standards.

What are Clean Air Zones (CAZ) and Low Emission Zones (LEZ)?

A CAZ or LEZ is an area within a city where a local authority has brought measures into place to improve the air quality.

Initially, it was thought that the Clean Air and Low Emission Zones would apply only to buses, taxis and HGVs. However, this was widened to include non-compliant private vehicles – meaning private motorists may be affected by them, not just commercial operators.

The creation of CAZs and LEZs in major UK cities is part of the government’s broader Air Quality Plan, which aims to improve air quality and urgently address sources of pollution.

By working at a regional level, it is hoped that local authorities and businesses can together take the most effective steps to contribute to improved air quality at a national level.

There are two types of Clean Air and Low Emission Zones: non-charging and charging.

In a non-charging CAZ/LEZ, the focus is on improving air quality without charging money for vehicles entering the zone itself. Measures can include retrofitting certain vehicles with pollution controls, traffic-flow management to reduce vehicle emissions (where evidence suggests this approach would be effective on the road in question), rerouting traffic or other local solutions.

In a charging zone, drivers must pay a fee to enter the area if their vehicle fails to meet the required environmental standards for that zone. Current requirements are based on a car's Euro emissions standard.

There are four classes of CAZ: A, B, C and D. They exempt various vehicles, but the emissions standards are broadly in line with the London Ultra Low Emission Zone (ULEZ). 

The specific class of each CAZ falls is determined by the local authority that implements it, but they are regulated by a national Clean Air Zone framework, outlined by the UK government in February 2020.

Why have Clean Air Zones (CAZ) and Low Emission Zones (LEZ) been introduced?

Government ministers were ordered by the Supreme Court to deliver measures aimed at tackling the levels of nitrogen dioxide (NO2) in the air, following pressure from environmental groups.

In 2019, a Public Health England (PHE) report estimated that between 28,000 and 36,000 deaths a year in the UK are attributed to long-term exposure to poor air quality.¹

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Where are Clean Air Zones (CAZ) and Low Emission Zones (LEZ) in the UK?

Bath

The Bath Clean Air Zone was introduced on 15 March 2021. A class C CAZ, it doesn’t charge private cars and motorbikes to pass through the zone, but buses and coaches, minibuses, light goods vehicles (vans, pick-ups and some camper vans) and trucks are charged.²

Bradford

Bradford has class C CAZ, which means private cars are not charged to enter the city. However, there are charges for taxis, vans, buses and HGVs that do not meet the emission standard.

Birmingham

The Birmingham CAZ was launched on 1 June 2021. A class D CAZ, all non-compliant vehicles are charged a fee from £8 to £50. In common with other CAZs, electric and hybrid vehicles do not incur a charge, and nor do motorcycles. However, the petrol or diesel engines in hybrid vehicles have to meet the relevant criteria.³

Bristol

The Bristol Clean Air Zone was introduced on 28 November 2022. The chargeable class D zone charges all high-emission vehicles to drive through the city centre, including private cars.⁴

London

The London Ultra Low Emissions Zone (ULEZ) has been in place since 2019 and was expanded in 2023 to include almost all of Greater London. Drivers of cars and vans that do not meet the minimum emission standard are required to pay a daily fee.

Glasgow

The Glasgow Low Emission Zone (LEZ) has been in place since June 2023. Drivers of non-compliant cars and vans are not permitted to enter the Glasgow LEZ, which makes it very different from the pay to drive model used in other cities. 

Manchester

The Greater Manchester CAZ is under review. Originally planned for a 2022 introduction, it would have charged private hire vehicles, vans, buses and HGVs to enter, but a lack of compliant vehicles and the rising cost of living has seen it shelved – for now. 

Newcastle and Gateshead

The Newcastle and Gateshead Clean Air Zone was introduced in 2023, covering  the city centre routes over the River Tyne. Private cars are not charged, but drivers of older taxis, vans, buses and HGVs may need to pay a fee to enter the CAZ.

Portsmouth

The Portsmouth Clean Air Zone was launched on 29 November 2021. Covering the south-west of the city, the class B CAZ excludes private cars, motorcycles and vans from any charges. Drivers of non-compliant taxis and private hire vehicles must pay £10 per day, however, and non-compliant HGVs, buses and coaches incur a charge of £50 per day.⁹

Sheffield

The Sheffield Clean Air Zone was implement in 2023. It's a class C CAZ, which sese buses, taxis, vans and lorries charged to drive in the zone. Charges are £10 per day for light good vehicles and taxis, rising to £50 per day for buses, coaches, and HGVs.

Clean Air Zone vehicle checker

The Government’s Joint Air Quality Unit have an online vehicle checker to help drivers prepare for Clean Air Zones.

Simply enter your vehicle’s registration number and this free tool will tell you if there’s a daily charge to drive your vehicle in a specific Clean Air Zone. More cities will be added as final plans become approved.

To check whether you’ll be charged for driving in the London ULEZ or LEZ, use the TfL vehicle checker instead.

^{1 https://www.gov.uk/government/news/public-health-england-publishes-air-pollution-evidence-review}

^{2 https://beta.bathnes.gov.uk/bath-clean-air-zone}

^{3 https://www.tfwm.org.uk/plan-your-journey/ways-to-travel/driving-in-the-west-midlands/birmingham-clean-air-zone/}

^{4 https://www.cleanairforbristol.org/caz/}

^{5 https://news.leeds.gov.uk/news/leeds-clean-air-charging-zone-launch-date-confirmed}

^{6 https://www.leeds-live.co.uk/news/leeds-news/doesnt-leeds-clean-air-zone-23185105}

^{7 https://confidentials.com/liverpool/clean-air-zone-liverpool}

^{8 https://cleanairgm.com/clean-air-plan/}

^{9 https://cleanerairportsmouth.co.uk}

^{10 https://www.bbc.co.uk/news/uk-england-hampshire-46807426}

^{11 https://tfl.gov.uk/modes/driving/ultra-low-emission-zone/ulez-expansion?cid=ulez-2021}

^{12 https://bradford.gov.uk/breathe-better-bradford/where-is-the-clean-air-zone/where-is-the-clean-air-zone/}

^{14 https://www.oxfordshire.gov.uk/residents/roads-and-transport/oxford-zero-emission-zone-zez}

^{15 https://www.sheffield.gov.uk/pollution-nuisance/clean-air-zone}

^{16 https://www.aberdeencity.gov.uk/services/roads-transport-and-parking/low-emission-zone}

^{17 https://www.dundeecity.gov.uk/service-area/city-development/sustainable-transport-and-roads/dundee-low-emission-zone-scheme}

^{18 https://www.glasgow.gov.uk/LEZ}