What is a Clean Air Zone (CAZ)?

UK cities are growing and facing the ongoing challenge of increased pollution. What is the UK Government doing to improve the situation? One strategy launched in 2015 is the concept of the Clean Air Zone (CAZ).

This article looks to explore Clean Air Zones, we’ll look at it’s definition, importance, and which cities in the UK are introducing clean air zones for their residents.

Silver VW ID.Buzz Van on charge

What is a Clean Air Zone?

A Clean Air Zone (CAZ) is an area where access is regulated in order to reduce air pollution and promote healthier environments. Typically, restrictions are placed on high-emission vehicles, encouraging cleaner modes of transport such as electric cars. The aim is to safeguard public health and the environment by improving air quality in city centres.

How does a Clean Air Zone work?

A Clean Air Zone (CAZ) is an area within a city in the UK where measures are put in place by local authorities to enhance air quality. Initially intended for buses, taxis, and HGVs, the scope now includes non-compliant private vehicles too!

These zones are part of the UK government’s Air Quality Plan, designed to reduce pollution by improving air quality. 

There are two primary types of CAZ in the UK:

  1. Non-charging CAZ
    Here, the emphasis is on air quality improvement without imposing entry charges. Methods might entail retrofitting vehicles with emission control mechanisms, managing traffic flow, rerouting traffic, or other bespoke solutions for the area.

  2. Charging CAZ
    In these zones, drivers must pay to enter if their vehicles don’t meet the environmental criteria, determined primarily by the vehicle’s Euro emissions standard.

What classes of Clean Air Zone are there?

There are four CAZ classes: A, B, C, and D. Each class has specific exemptions and aligns closely with London’s Ultra Low Emission Zone (ULEZ) standards. The particular class designation of a CAZ is decided by the local authority under the national Clean Air Zone framework, which was presented by the UK government in February 2020.

  • Class A: Buses, coaches, taxis, private hire vehicles.
  • Class B: Adds heavy goods vehicles to Class A.
  • Class C: Incorporates vans, minibuses in addition to vehicles in Class B.
  • Class D: Includes cars, and local authorities can choose to add motorcycles to the vehicles listed in Class C.

What are the minimum CAZ emission standards?

Each vehicle type has a set emission standard. You can check your vehicle’s emission standard in the logbook or inquire from the manufacturer. To be exempted from CAZ charges:

  • Buses, coaches, heavy goods vehicles should have Euro 6.
  • Vans, minibuses, taxis, private hire vehicles, cars should have Euro 6 (for diesel) and Euro 4 (for petrol).
  • Motorcycles should be at least Euro 3.

Standards for taxis and private hire vehicles vary by local authorities.

What vehicles are allowed in a clean air zone?

Several national and local exemptions exist that allow certain vehicles into clean air zones. You’re automatically exempted from the charge if your vehicle is:

  • Ultra-low emission.
  • A disabled passenger or tax class vehicle.
  • Military.
  • Historic.
  • Retrofitted with Clean Vehicle Retrofit Accreditation Scheme (CVRAS)-accredited technology.
  • Certain agricultural vehicles.
electric white tradesman delivery van on charge
Zero-emission electric delivery vans are allowed in clean air zones

How to use the Government Clean Air Zone checker

If you need to find out if your car emissions are eligible for a particular clean air zone, you can use the Gov clean air zone emission checker. This is a neat tool that lets you check your car emissions by registration. Here’s how you can use it:

  1. Access the Clean Air Zone Checker
    Here’s a link to the Government Clean Air Zone Checker.

  2. Enter Your Vehicle Registration
    On the first page, you’ll find a field prompting you to enter your vehicle’s registration (number plate). Type in your number plate and hit proceed.

  3. Confirm Your Vehicle Details
    The system should find your car and display your details based on the number plate provided. Ensure the details are accurate and hit the ‘confirm’ button.

  4. Review the Results
    So the next page will show you the results for all current clean air zones. You’ll be shown whether there’s a daily charge for your vehicle to enter each specific clean air zone. This page only informs you about potential charges and does not show any unpaid charges you may have already received.

  5. Understanding Your Results
    The results will be displayed in a table, this is what the columns mean:
    • Clean Air Zone: This column names the specific zone.
    • Daily Charge: Here, you’ll find if there’s a fee for your vehicle to enter the zone. “No Charge” indicates you can enter without paying a fee based on your vehicle’s emission standards.
    • Zone Status: This tells you if the zone is currently active (“Now”) or if its status is under review.
    • Zone Map Link: Clicking this will open a map showing the exact boundaries of the clean air zone.
    • Exemptions Link: This leads to the respective city council’s page where you can find detailed information about exemptions or potential reductions.

By following the steps above, you can easily check whether your vehicle is subject to any charges in the UK’s clean air zones. It’s a handy tool for planning journeys and understanding the potential costs associated with driving in different areas of the country.

How to pay a clean air zone charge?

You can pay a clean air zone charge using the following steps:

  • Check if your vehicle incurs a CAZ charge using the government’s online CAZ service.

  • CAZs operate 24/7, 365 days a year.

  • Pay the charge within six days of entering the CAZ or up to six days prior to your journey. If you miss the deadline, you’ll receive a penalty charge notice (PCN).

  • The maximum transaction limit is £5,000. If your payment exceeds this, you’ll have to make multiple transactions.

  • Businesses with two or more UK-registered vehicles can set up an account to manage payments. This account allows businesses to manage multiple vehicles, view charges, add team members, and more.

Which cities have Clean Air Zones in the UK?

Bath
Operational since 15 March 2021, Bath’s class C CAZ charges buses, coaches, minibuses, light goods vehicles, and trucks but exempts private cars and motorbikes.

Birmingham
This class D CAZ, in effect since 1 June 2021, charges all non-compliant vehicles, with fees ranging from £8 to £50. Electric, hybrid vehicles and motorcycles are exempt if they meet the set criteria.

Bristol
Bristol’s class D CAZ charges all high-emission vehicles, including private cars.

Bradford 
Bradford has class C CAZ charges in place.

Portsmouth
Established on 29 November 2021, this class B CAZ in Portsmouth’s south-west exempts private cars, motorcycles, and vans from charges but imposes fees on non-compliant taxis (i.e. anything that is not classified as an electric taxi), HGVs, buses, and coaches.

Sheffield
In Sheffield, a Class C Clean Air Zone is in place. This means that the most polluting heavy goods vehicles (HGVs), light goods vehicles (LGVs), vans, buses, coaches, and taxis that operate within this zone will be subject to charges.

Tyneside – Newcastle and Gateshead
The Tyneside CAZ is in place for taxis, vans, buses, coaches and heavy goods vehicles that do not meet national Clean Air Zone emissions criteria.

Does London have a clean air zone?

While London boasts its Ultra Low Emission Zone (ULEZ) that functions similarly to a Clean Air Zone, it remains separate and is regulated differently to the CAZ legislation.

What about Scotland’s Low Emission Zones?

Scotland has introduced Low Emission Zones (LEZs) in several of its major cities. These zones aim to restrict the most polluting vehicles from entering designated areas, rather than imposing a blanket ban on all vehicles.

Where are Scotland’s Low Emission Zones?

Glasgow
Started on 1 June 2023, but residents within the zone have been granted an additional grace year.

Dundee
The city’s LEZ will start its enforcement from 30 May 2024.

Aberdeen and Edinburgh
Both cities are set to begin their LEZ enforcement on 1 June 2024.

Which vehicles does Scotlands Low Emission Zone cover?

The primary goal of the LEZs is to encourage the use of vehicles that meet minimum emission standards, which are determined based on the Euro category of the vehicle.

  • Diesel Cars and Vans
    Vehicles should meet the Euro 6 standard. Typically, this encompasses vehicles registered from September 2015 onwards.
  • Petrol Cars and Vans
    The required standard is Euro 4, which generally pertains to vehicles registered from 2006.

To work out if your car meets these standards, you can check online on the Low Emission Zone Scotland website.

Payments and penalties in Scotland

Currently, there is no provision to pre-register or pre-pay for entering a LEZ in Scotland. Instead, the system operates on a penalty-based model. If a non-compliant vehicle enters the zone, a Penalty Charge Notice (PCN) is automatically issued to the vehicle’s registered keeper.

Why do we need clean air zones?

Clean air zones (CAZs) are needed to safeguard public health and the environment. 

They target polluted air and pollutants that can hurt us and cause respiratory conditions such as asthma. Particularly concerning is the fact that children exposed to high levels of these pollutants are more susceptible to respiratory diseases in adulthood and can experience stunted lung growth. The World Health Organization estimates that air pollution causes around seven million premature deaths globally each year.

There are also plenty of environmental benefits of CAZs. Pollutants pose a threat to ecosystems and wildlife which if left unchallenged can cause irreversible global issues.

What are the negatives of clean air zones?

Clean air zones have had their share of criticisms since being introduced to the UK in 2015.

One of the primary concerns revolves around the financial implications for businesses, particularly those reliant on older vehicles. Local delivery services and tradespeople might find themselves particularly affected. However, these can be offset over the long term by the cheaper running costs of EVs.

There’s also the risk that instead of reducing emissions, CAZs merely displace them. Drivers, to get around CAZ charges, might choose longer routes, inadvertently increasing emissions in areas next to the CAZ.

How do I know if I’ve been in a clean air zone?

There are a few ways to find out if you have been in a Clean Air Zone:

  1. Road Signs
    When approaching or entering a CAZ, there should be clear road signs indicating the beginning of the zone. These signs are designed to be easily recognizable and will indicate the type of CAZ (e.g., Class A, B, C, D) and the vehicles affected.

  2. Maps and Local Government Websites
    Local authority or government websites often provide maps or detailed boundaries of the clean air zones. Before travelling to an unfamiliar city or area, it’s a good idea to check these resources.

  3. GPS and Navigation Apps
    GPS devices and smartphone maps may have features that alert you when you are approaching or have entered a CAZ.

The final word on clean air zones

Clean air zones represent a really positive move by UK cities to prioritize public health and the environment. 

By targeting the most polluting vehicles, CAZs serve as a great incentive for drivers to adopt electric cars. 

While they come with challenges, especially for businesses and lower-income tradespeople who may find it too expensive to upgrade older vehicles quickly, the broader objective remains clear: to push the UK to a future where city centres have cleaner air.


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