How to Check if Your Car is ULEZ, LEZ, or CAZ Compliant

If you’re planning to drive in London or other major UK cities, you’ll need to know whether your car is compliant with ULEZ (Ultra Low Emission Zone), LEZ (Low Emission Zone), or CAZ (Clean Air Zone).

Failing to check can mean daily charges — or hefty fines. In this article, we’ll explain what each zone means, how they differ, and the simplest way to find out if your vehicle is compliant.

What’s the Difference Between ULEZ, LEZ, and CAZ?

🚗 ULEZ (Ultra Low Emission Zone)

• Focused on cars, vans, motorcycles, and smaller vehicles.
• Applies across all London boroughs (since 2023).
• Operates 24/7, all year (except Christmas Day).
• Daily charge: £12.50 for non-compliant vehicles.

🚛 LEZ (Low Emission Zone)

• Covers heavier vehicles like lorries, buses, coaches, and larger vans.
• Has been in place across most of Greater London since 2008.
• Charges vary depending on vehicle weight and emissions.

🌍 CAZ (Clean Air Zone)

• Similar concept, applied in other UK cities (Birmingham, Bath, Bristol, Oxford, Manchester, etc.).
• Four classes (A–D) depending on vehicle types included.
• Charges and rules vary by city — not every car is affected.

Why Compliance Matters in 2025

• Non-compliant vehicles face daily charges (£12.50 in London, £8–£10 in other cities).
• Penalty fines apply if you fail to pay.
• Driving in multiple cities? You may face different rules in each zone.

How to Check if Your Car is Compliant

The easiest way is to use a vehicle registration plate checker:

1. Go to a compliance tool (like CheckVehicle.ai).
2. Enter your vehicle registration number.
3. Get instant results showing whether your car is:
   • ✅ ULEZ compliant
   • ✅ LEZ compliant
   • ✅ CAZ compliant in multiple cities

👉 Check Your Vehicle Now with CheckVehicle.ai

This saves time compared to manually looking up Euro standards and city-by-city rules.

Vehicle Standards (Quick Reference)

• ULEZ (London, 2025):
  • Petrol cars: Euro 4 (2006+).
  • Diesel cars: Euro 6 (2015+).
  • Motorcycles: Euro 3 (2007+).
• LEZ (London):
  • Heavy diesel vehicles must meet Euro VI standards.
• CAZ (Cities like Birmingham, Bath, Bristol, Manchester):
  • Cars: Euro 4 (petrol) / Euro 6 (diesel).
  • Charges vary (£8–£10 daily for cars in some zones).

Exemptions & Discounts

Some drivers don’t have to pay or may qualify for discounts:

• Historic vehicles (40+ years old).
• Electric & hydrogen vehicles (always exempt).
• Blue Badge holders (may receive exemptions in certain zones).
• Local residents (in some cases, temporary grace periods).

Common Questions

Q: Is ULEZ the same as the Congestion Charge?
No — ULEZ is about emissions, while Congestion Charge is about reducing traffic. You may have to pay both if driving into central London.

Q: Does ULEZ apply outside of London?
No, but other cities run CAZ schemes with similar rules.

Q: Can I drive through a CAZ without paying if I’m compliant?
Yes, if your vehicle meets the Euro standards, you won’t need to pay.

Preparing for the Future

As the UK heads towards the 2035 petrol/diesel sales ban, zones like ULEZ, LEZ, and CAZ will only get stricter. Drivers should:

• Check compliance before buying a used car.
• Factor in future rules when deciding on petrol, diesel, or EV.
• Consider switching to hybrid or electric sooner.

Key Takeaways

• ULEZ targets small vehicles in London.
• LEZ covers larger/heavier vehicles in London.
• CAZ applies in other UK cities, with varying rules.
• The easiest way to know if you’ll pay: use a reg plate checker.
• Don’t risk fines — check before you drive.