Clean Air Zones Explained: What You Need to Know

As the UK government continues its efforts to combat air pollution, one of the key strategies is the implementation of Clean Air Zones (CAZ). These zones are designed to reduce harmful emissions from vehicles, but understanding exactly what the rules are can be confusing.

In this guide, we'll take a closer look at what Clean Air Zones are, why they've been introduced and how they work. We'll also cover where you can expect to find them, what types of vehicles are affected and how CAZ charges work.

Clean Air Zones (CAZ) have been introduced around England and Scotland by local authorities to help improve air quality. If your vehicle doesn’t meet emission standards, you’ll have to pay a charge to drive within one.

These are similar but separate to London’s Ultra Low Emission Zone (ULEZ). This zone covers all areas within the North and South Circular Roads. 

To tackle harmful air pollution in cities and towns across the UK, Clean Air Zones (CAZ) have been introduced. Vehicle emissions, particularly from older diesel and petrol engines, release pollutants like nitrogen dioxide (NO₂) and particulate matter (PM), which can cause serious health problems, including respiratory diseases, heart conditions, and even premature death.

By encouraging drivers to switch to cleaner, lower-emission vehicles or to use alternative forms of transport, CAZ helps improve air quality, protect public health, and reduce the environmental impact of road traffic. They also play a key role in supporting the UK’s commitment to meet legal air quality standards and climate change goals.

As of June 2025, there are currently 7 Clean Air Zones (CAZ) operating across the UK. These zones have been introduced to help reduce air pollution by encouraging the use of cleaner vehicles.

• Bath - Class C Clean Air Zone
• Birmingham - Class D Clean Air Zone
• Bradford - Class C Clean Air Zone
• Bristol - Class D Clean Air Zone
• Portsmouth - Class B Clean Air Zone
• Sheffield - Class C Clean Air Zone
• Tyneside (Newcastle and Gateshead) - Class C Clean Air Zone

For the most up-to-date information on CAZ locations, check out Clean Air Zone guidance on gov.uk.

There are 4 classes of Clean Air Zones (CAZ), which determine which types of vehicles may be subject to a charge if they do not meet emissions standards:

• Class A - Buses, coaches, taxis, and private hire vehicles
• Class B - Buses, coaches, taxis, private hire vehicles, and heavy goods vehicles (HGVs)
• Class C - Buses, coaches, taxis, private hire vehicles, HGVs, vans, and minibuses
• Class D - Buses, coaches, taxis, private hire vehicles, HGVs, vans, minibuses, and cars (local authorities may also choose to include motorcycles)

If your vehicle does not meet the minimum emission standard for a Clean Air Zone (CAZ), you may need to pay a daily charge when driving within a zone.

To avoid paying the charge, your vehicle must meet at least the following emissions standards:

• Cars, vans, minibuses, taxis, and private hire vehicles:
• Euro 4 for petrol
• Euro 6 for diesel
• Buses, coaches, and heavy goods vehicles (HGVs):
• Euro VI (6)
• Motorcycles and mopeds:
• Euro 3

You can usually find your vehicle’s Euro emission standard in your V5C log book, by contacting your vehicle manufacturer, or by checking with services such as the RAC or the on the gov.uk official vehicle checker.

There are also national and local exemptions for certain types of vehicles, such as historic vehicles, disabled tax class vehicles, and some types of agricultural machinery. For full details, visit the Clean Air Zone exemptions page on gov.uk.

Clean Air Zones operate 24 hours a day, 7 days a week, every day of the year - including Sundays and public holidays.

If you're planning to drive through a CAZ, you should use the official Clean Air Zone service on gov.uk to:

• Check if your vehicle is subject to a charge
• Find out how much you need to pay
• Pay the daily charge
• View maps of current Clean Air Zones

With the ongoing cost-of-living pressures, affording CAZ charges can be challenging for some drivers. The Office for Zero Emission Vehicles (OZEV) offers grants to help individuals and businesses switch to cleaner vehicles, such as electric or plug-in hybrids. In addition, some local authorities may provide funding or support schemes to help you upgrade or replace your vehicle with a compliant one.

While both Clean Air Zones (CAZ) and the Ultra Low Emission Zone (ULEZ) aim to reduce air pollution and encourage the use of cleaner vehicles, they differ in how they’re implemented and where they apply.

Clean Air Zones are set up by local councils in cities across the UK. Each one is a bit different depending on the area. Some only charge buses and taxis, while others also apply to vans and private cars. It all depends on the class of the zone, from Class A (least strict) to Class D (most strict). Whether you’re charged or not usually comes down to how polluting your vehicle is.

The ULEZ is London’s version, and it’s run by Transport for London. It’s tougher than most CAZs because it applies to pretty much all vehicles, including private cars and motorcycles. If your vehicle doesn’t meet the emissions standards (Euro 4 for petrol, Euro 6 for diesel), you’ll need to pay a daily charge to drive in the zone.

If you drive a vehicle that doesn’t meet the Ultra Low Emission Zone (ULEZ) standards, you’ll need to pay a daily charge to drive within the ULEZ area in London. The charge applies to most vehicle types, including cars, vans, motorcycles, and minibuses.

To avoid the ULEZ charge, your vehicle must meet the following emissions standards:

• Petrol vehicles must meet at least Euro 4
• Diesel vehicles must meet at least Euro 6
• Motorcycles must meet Euro 3

These standards are based on how much pollution your vehicle emits. Many older vehicles, particularly older diesels, do not meet the requirements. However, most newer vehicles, especially electric, hybrid, or efficient petrol models, already meet these requirements. You can explore and learn more about a wide range of low-emission options in our Electric Hub.

If you’re not sure if your vehicle is compliant, you can check quickly and easily using the official TfL ULEZ vehicle checker.

The Congestion Charge Zone is an area in central London where drivers are required to pay a daily fee to help reduce traffic and improve flow through the city. It’s aimed at cutting congestion, not necessarily emissions, which makes it different from schemes like the ULEZ or Clean Air Zones (CAZ).

The charge applies during specific hours on weekdays, weekends, and bank holidays—but not on Christmas Day through New Year’s Day. The rules apply to most vehicles, including electric ones, unless you’re eligible for an exemption or discount.

Unlike the ULEZ and CAZ, which are based on your vehicle’s emissions, the Congestion Charge applies regardless of how clean your vehicle is. That means even low-emission or zero-emission vehicles may still need to pay unless registered for a discount.

To find out when the charge applies, who needs to pay, how much it costs, and how to check if you're entering the zone, visit the official TfL Congestion Charge page.

From 2030, the UK plans to end the sale of new petrol and diesel cars, meaning only electric or zero-emission vehicles will be available to buy new.

If you want to get ahead, we have hundreds of cleaner vehicles for sale at over 50 locations across the UK.

• Browse our used EVs
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