Clean Air Zones latest

7 min to readFleet management
What is a Clean Air Zone? Where and when are they being introduced? What will they charge? And what vehicles will be restricted? Our guide explains all.
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What is a Clean Air Zone?

Simply put, a Clean Air Zone (CAZ) is an area where special measures are taken to improve air quality.

That's it?

No. There are, broadly speaking, two types of CAZ:

Why are they being introduced?

In 2010, the UK signed up to a number of limits on air pollution - including limits on harmful nitrogen dioxide (NO2) emissions. At the same time, the Government committed to publishing Air Quality Plans whenever those limits are breached.

The limits for NO2 have been breached in every year since their introduction - and so, after a series of legal challenges, the Government has had to publish several Air Quality Plans. The latest of these, which was released in 2017, directed 29 of the most polluted local authorities to draw up their own plans for reducing NO2, which could include the introduction of CAZs.

After another legal challenge in 2018, a further 33 local authorities received the same directive.

Many of these local authorities were told to reveal their clean air plans by the end of 2018. Once those plans have been approved, which generally happens after a process of consultation with local populations and with national politicians, they can then be funded and implemented. CAZs were initially expected to be introduced from 2020, but the Covid pandemic pushed back the timings on many of them.

Who decides on the parameters of a CAZ?

The Government's Air Quality Plan leaves the responsibility to councillors. So long as a local authority's clean air plan does enough to reduce NO2 as quickly as possible, then it is up to the local authority to decide whether that plan includes a CAZ, whether that CAZ is charging or non-charging, the boundaries of that CAZ, and the policies that apply within it.

The Air Quality Plan does place some constraints on councils, however - including its stipulation that a charging CAZ should only be introduced if non-charging measures will not, by themselves, reduce air pollution swiftly enough.

All of this means that different areas will have different clean air policies. Some will have charging CAZs, others will not. Some will charge less, others will charge more. Some will operate for 24 hours a day, others will be time limited. Knowing and meeting these conditions will be a particular challenge for fleets that travel from area to area.

Which vehicles will be affected?

Again, it is up to local authorities to decide which vehicles - if any - will be charged within a CAZ. However, the Government has provided some guidance. The Air Quality Plan describes four classes of CAZ, depending on the vehicles that are charged within them:

The four classes of charging Clean Air Zone

The Clean Air Zone Framework also recommends the minimum emission standards that should apply within a CAZ, although it notes that 'these minimum standards represent a good starting point but should not limit ambition?. Vehicles that meet these standards should avoid charges:

Charging Clean Air Zone minimum emission standards

Are any CAZs in operation already?

London has effectively been operating a CAZ for over a decade, even if it does not go by that name. The capital's Low Emission Zone (LEZ) has imposed a fee on older, dirtier vans and lorries since 2008.

In 2017, the city's Mayor, Sadiq Kahn, introduced a special 't-charge' for cars and other vehicles that do not meet minimum emission standards. On 8 April 2019, that charge was replaced by a full-blown Ultra-Low Emission Zone (ULEZ).

Non-compliant cars and vans pay £12.50/day to drive within the ULEZ - which currently covers the same area of Central London as the (still active) Congestion Charge Zone. Buses, coaches and HGVs that do not meet the emission standards are charged £100/day.

From 25 October 2021 the ULEZ was extended up to the North and South Circular roads. Traffic using those roads but not entering Central London will not be charged.

For more information about London's ULEZ, please visit the TfL website here.

London boroughs

Hackney and Islington Councils, which form part of the 2021 extended ULEZ, have banned all non-Ultra Low Emission Vehicles (i.e. those emitting more than 75g/km) from two streets in Shoreditch, from 7 to 10am and 4pm to 7pm on Monday to Friday. Businesses and residents located in these zones can register for an exemption.

Which other areas have introduced a CAZ or are planning to?

A number of local authorities outside London have signalled their intention to introduce charging CAZs. These plans were temporarily suspended while councils focused on the pandemic, but some have been introduced, and many will be introduced in 2022.


Basildon and Rochford Councils are fighting a Government order to introduce a CAZ on the A127, arguing that installing a new cycle route, investing in rapid charging points and reducing speed limits is a better way to tackle illegal levels of NO2.


Bath City Council introduced a Class C charging CAZ on 15 March 2021. Non-compliant HGVs, buses and coaches will pay £100/day, taxis, minibuses and vans will be charged £9/day. Cars and motorcycles will be exempt.


Launched on 1 June 2021, Birmingham's CAZ charges £8/day for all non-compliant cars, taxis, and LGVs. Non-compliant HGVs, coaches and buses will pay £50/day. It is effective for 24 hours a day, 365 days a year.

Birmingham City Council has also published a draft transport plan that proposes further measures over the next decade, including banning private vehicles from travelling through the city centre and only entering and leaving through certain areas. They also propose rerouting the A38 and bringing in a 20mph limit on more residential roads.


Bradford is planning to introduce a Class C CAZ in 2022, with daily charges of up to £50. However, this relies on a Government grant for implementation, which has not yet been confirmed.


Bristol is planning to introduce a Class D CAZ in its city centre in summer 2022. This will affect all vehicles that don't meet its requirements, with a charge of £9 for cars, taxis and vans, and £100 for HGVs, buses and coaches. There will be a one-year exemption for drivers of older vehicles.


Cambridge City Council is currently studying the feasibility of a CAZ in the historic centre.


Since 2019, Glasgow has had a LEZ in force, currently applying only to some buses. However, it will apply to lorries, vans and private cars from 1 June 2023.


Due to improved air quality over the past three years, Leicester is no longer required to introduce a CAZ.


After putting its CAZ plans on hold to assess their viability, Liverpool is now looking to introduce a consultation about charging and other potential measures to improve air quality.


Manchester is planning to introduce a CAZ on 30 May 2022 for buses, HGVs, LGVs and private-hire vehicles. Its Mayor has said that there will be no charging scheme for private vehicles.

Newcastle and Gateshead

Newcastle and Gateshead plan to introduce a charging CAZ for high-emission vehicles in July 2022. Non-compliant HGVs, buses and coaches would be charged £50 to enter the city centre, while taxis and vans are charged £12.50. Private cars will not be included. They also aim to cut traffic on the Tyne Bridge to one lane in each direction.


Oxford City Council plans to introduce a Zero Emission Zone (ZEZ) in parts of the city centre in February 2022. This 'red zone' will impose a charge of £10 on all petrol and diesel vehicles that enter it between 7am and 7pm. There are also plans for an expanded 'green zone' zone, covering the rest of the centre, which will offer reduced charges for petrol and diesel vehicles that are compliant with London's ULEZ standards.


Portsmouth introduced a Class B charging CAZ in November 2021. Non-compliant buses, coaches, taxis, private hire and HGVs pay up to £20/day. Cars are exempt.


Sheffield is planning a Class C CAZ that is due to be introduced in late 2022.


Southampton has a non-charging CAZ and is using other measures to improve air quality further.


York introduced a bus-based CAZ in early 2021, and has witnessed sufficient air quality improvements that the City Council expects to take no further action.

Other areas

Other areas where CAZs (of various types, but mostly non-charging) could be introduced include:

Brighton, Canterbury, Cardiff, Coventry, Derby, Exeter, Leeds and Nottingham have ruled out a CAZ or have no plans to introduce one.

This list will be updated as more information becomes available. Last updated 24 December 2021.

Published at 24 December 2021
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