Clean Air Zones explained

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.

Motoring is getting greener. Partly due to the innovations of manufacturers and the choices made by fleets and their drivers. But also due to local and national government initiatives.

One of these initiatives is the Clean Air Zone (CAZ) – something that you will be hearing a lot about, as more of them come online over the next year or so. Here’s our guide to what they mean for you.

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. Various local authorities will be introducing CAZs over the next few years.

That’s it?

No. There are actually two types of CAZ:

  • Charging CAZ. This type of CAZ imposes a fee on any vehicles passing through it that do not meet minimum emission standards.
  • Non-charging CAZ. This type of CAZ does not impose fees on vehicles passing through it. Instead, it relies on other measures to improve air quality. Examples of such measures – as suggested by the Government’s Clean Air Zone Framework – are improved public transport links, refined road layouts, and more cycle lanes.

It should be noted that charging CAZs can also contain non-charging elements.  

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. It is expected that most CAZs will be introduced in 2020 and 2021.

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

Class                      Vehicles potentially included

  • A                       Buses, coaches, taxis, private hire vehicles
  • B                       Class A and HGVs
  • C                       Class A + Class B + large vans, minibuses, small vans
  • D                       Class A + Class B + Class C + cars, motorcycles, mopeds

Source: Department for Environment, Food and Rural Affairs; Department for Transport (DfT)

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

Vehicle type                                                        Minimum emission standards

  • Buses and coaches                                   Euro VI
  • HGVs                                                            Euro VI
  • Vans                                                             Euro 6 (diesel) or Euro 4 (petrol)
  • Cars                                                              Euro 6 (diesel) or Euro 4 (petrol)
  • Motorcycles and mopeds                       Euro 3

Source: Department for Environment, Food and Rural Affairs; Department for Transport (DfT)

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 will be extended 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 read our online guide.

London Boroughs

Hackney and Islington Councils, which will be part of the 2021 extended ULEZ, are proposing going a step further and banning all non-Ultra Low Emission Vehicles (i.e. emitting more than 75g/km) from two zones in Shoreditch, 7-10am and 4-7pm Mon-Fri. If approved, businesses and residents located in these zones will be able to register for an exemption.

Which other areas are planning to introduce CAZs?

Several local authorities outside London have signalled their intention to introduce charging CAZs. Leeds and Birmingham will be first.


Birmingham’s CAZ will impose an £8/day charge on all non-compliant cars, taxis, and LGVs from July 1 2020. Non-compliant HGVs, coaches and buses will pay £50/day.

Birmingham City Council have also published a draft transport plan which 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.


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


Bath City Council is awaiting government approval for a Class C charging CAZ planned for November. Non-compliant HGVs, buses and coaches will pay £100/day; taxis, minibuses and will be vans will be charged £9/day. Cars and motorcycles will be exempt.


Brighton and Hove’s city council currently have no plans to introduce a charging CAZ. However, the Green Party are pressing for a complete ban on petrol and diesel cars from the centre, something opposed by the ruling Labour Party.


Bristol City Council have agreed plans for a ‘hybrid’ CAZ, which will see all diesel cars banned from entering parts of the city centre.

The plans include a charging CAZ that would levy only non-compliant commercial vehicles: LGVs £9/day; buses, coaches and HGVs £100/day. But also, controversially, a blanket ban on private diesel cars entering a small inner city ‘core’ area of the CAZ, between 0700-1500hrs.

If approved by Whitehall, the scheme would be implemented in March 2021. But Bristol’s plan has been met with concern from some quarters. In part because the ban on all private diesels departs from government CAZ guidelines – failing to distinguish between older, more polluting vehicles and much cleaner modern Euro 6 standards which emit less NO2 than some of the older petrol cars permitted in the inner zone.


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


Derby, which was originally expected to introduce a charging CAZ, is now planning a non-charging CAZ.


Since 2019 Glasgow has had an LEZ in force, currently applying only to some buses. However, from December 31 2022 it will apply to lorries, vans and private cars.


Leicester is proposing introducing a small CAZ in the Summer of 2021. Non-compliant taxis charged £8/day and buses £50/day. Vans and cars exempt.


Leeds’ CAZ will not impose fees on private cars and vans, but non-compliant HGVs, buses, coaches will pay £50/day, taxis and private hire vehicles £12.50/day. To be introduced mid-2020 (date TBA).


Manchester is planning to introduce a £100/day charging CAZ for non-compliant HGVs in 2021 – expanding to £7.50/day for non-compliant vans, minibuses, motorhomes and motorised horseboxes in 2023.

Newcastle and Gateshead

Newcastle and Gateshead plan (subject to government approval) to introduce a charging CAZ for high emission vehicles in 2021. Non-compliant HGVs, buses and coaches would be charged £50 to enter Newcastle City Centre, taxis and vans, £12.50. Cars initially exempt.

They also aim to cut traffic on the Tyne Bridge to one lane in each direction.


Oxford City Council proposes gradually turning the city centre into a Zero Emission Zone (ZEZ), starting with banning all non-zero emission vehicles from parking and loading during certain hours in an inner zone, with a Euro 6 requirement for buses in a larger zone. In the Council’s own words, ‘a ZEZ could apply to some vehicles and journey types, with restrictions increased gradually to all vehicles in the following years to create a largely transport emissions-free city centre by 2035.’


Portsmouth proposes introducing a Class B charging CAZ (date TBC). Non-compliant buses, coaches, taxis, private hire and HGVs would pay up to £20/day. Cars exempt.


Sheffield is also planning to introduce a charging CAZ in late 2020, which exempts cars.


Southampton is now planning a non-charging CAZ.


The City of York Council proposes banning private cars from York’s city centre by 2023.

Other areas

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

  • Aberdeen
  • Caerphilly
  • Dundee
  • Edinburgh
  • Fareham
  • Liverpool
  • Slough
  • St Albans
  • Warrington
  • Wokingham

Basildon, Canterbury, Cardiff, Exeter and Nottingham have all ruled out a CAZ.

This list will be updated as more information becomes available.

Further information

For more information and guidance on Clean Air Zones and operating vehicles in the Ultra Low Emission Zone (ULEZ) please speak to your LeasePlan Account Manager. If you’re not yet a LeasePlan customer, please call  01753 802448 or email 

(last updated 20 January 2020)




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