Air quality and sustainability are at the heart of the UK’s transport future. Two key initiatives driving cleaner travel are the Ultra Low Emission Zone (ULEZ) and Clean Air Zones (CAZ).
If you drive regularly, understanding how these zones work can help you avoid unnecessary charges, make smarter car-buying decisions, and contribute to a cleaner environment.
What Are ULEZ and CAZ?
Both ULEZ and CAZ aim to reduce vehicle emissions, but they are managed by different authorities and apply in different areas.
ULEZ (Ultra Low Emission Zone)
Introduced by: Transport for London (TfL)
Area covered: All London boroughs (Greater London)
Goal: Reduce nitrogen dioxide (NO₂) and particulate matter in the capital’s air
How it works: Vehicles must meet strict Euro emission standards to drive without paying a daily charge
CAZ (Clean Air Zone)
Introduced by: Local councils outside London
Cities include: Birmingham, Bristol, Sheffield, Bath, and Glasgow (Low Emission Zone in Scotland)Bath, Birmingham, Bradford, Bristol, Glasgow (Low Emission Zone), Leeds, Liverpool, Newcastle and Gateshead (Tyneside CAZ), Nottingham, Portsmouth, and Sheffield.
Goal: Improve air quality in city centres by discouraging high-emission vehicles
How it works: Depending on the city, some or all vehicle types may be charged if they do not meet emission standards
In short:
ULEZ is specific to London and applies to almost all vehicles.
CAZ schemes operate in other UK cities, and the rules can vary depending on the type of zone.
ULEZ and CAZ Charges
If your vehicle does not meet the required emission standards, you’ll need to pay a daily charge to drive in these zones.
ULEZ (London): £12.50 per day for cars, vans (up to 3.5 tonnes), and motorcycles
CAZ (outside London): Charges vary by city and vehicle type
For example, in Birmingham, non-compliant cars and vans are charged £8 per day, whilst in Bristol, private cars that do not meet standards also pay £9 per day.
Failing to pay the charge can result in a Penalty Charge Notice (PCN). The exact amount depends on the local authority.
What Are the Emission Standards?
ULEZ and CAZ both use Euro emission standards to decide which vehicles qualify.
Vehicle Type | Minimum Standard | Typical Registration Year |
Petrol cars | Euro 4 | 2005 or later |
Diesel cars | Euro 6 | 2015 or later |
Motorbikes | Euro 3 | 2007 or later |
Electric vehicles | Zero emissions | Fully compliant |
You can check whether your vehicle meets the standards on your local authority’s website or the TfL Vehicle Checker.
ULEZ and CAZ: What Drivers Should Consider When Buying a Car
If you live in or travel through ULEZ or CAZ areas, it’s worth planning ahead when buying your next car. Here’s what to keep in mind:
1. Check Compliance Before You Buy
Always confirm that the vehicle meets Euro 4 (petrol) or Euro 6 (diesel) standards. This ensures you can drive in any low-emission zone without paying daily fees.
2. Go Electric or Hybrid
Electric vehicles (EVs) produce zero tailpipe emissions and are fully compliant across all ULEZ and CAZ areas. Hybrids often meet Euro 6 standards and offer improved fuel efficiency. Government grants for electric vehicles help to make the switch to an EV easier.
3. Think Long-Term
More cities are introducing CAZ or Low Emission Zones each year. Choosing a low- or zero-emission vehicle now can help you stay ahead of future regulations.
The Positive Impact of ULEZ and CAZ Across the UK
ULEZ and CAZ zones have already made a noticeable difference in air quality across the UK.
Cities like London, Birmingham, Bristol, and Glasgow have reported a reduction in nitrogen dioxide levels, cleaner air, and an increase in the number of low-emission vehicles on the road.
These zones help to improve public health as well as encourage innovation in electric vehicle technology and charging infrastructure. By driving cleaner vehicles, we’re all helping to build a more sustainable transport system for the entire country.
- Electric