Whether you already own a car and need to know if it will be charged in a Clean Air Zone, or you are about to buy a used car and want to make sure it is compliant — this guide covers both scenarios. The check takes less than 30 seconds if you have a registration number, and we will also show you how to assess compliance without one.

1. The 30-Second Check (With a Registration Number)

If you have the car’s registration number, you can check ULEZ and Clean Air Zone compliance instantly using two free government tools.

For London ULEZ:

  1. Go to tfl.gov.uk/modes/driving/check-your-vehicle
  2. Enter the vehicle registration number
  3. The result will tell you whether the vehicle meets ULEZ emission standards

For all other UK Clean Air Zones:

  1. Go to gov.uk/check-clean-air-zone-charge
  2. Enter the registration number
  3. Select which Clean Air Zone you want to check
  4. The tool will confirm whether a charge applies and how much it is
Pro Tip: The TfL checker and GOV.UK checker use the same underlying data from the DVLA. If a car passes the TfL ULEZ check, it will pass every other Clean Air Zone in the UK that uses Euro emission standards as the compliance threshold.

2. Understanding Euro Emission Standards

Clean Air Zone compliance is determined by your vehicle’s Euro emission standard. Here is a complete breakdown of every Euro standard, when it applied, and whether it passes.

Euro StandardPetrol — Approx. YearsDiesel — Approx. YearsULEZ/CAZ Compliant?
Euro 11993–19961993–1996No
Euro 21997–20001997–2000No
Euro 32001–20052001–2005No
Euro 42006–20102006–2010Petrol: Yes / Diesel: No
Euro 52011–20152011–Aug 2015Petrol: Yes / Diesel: No
Euro 6Sept 2015 onwardsSept 2015 onwardsYes

The key rules:

  • Petrol cars need to be Euro 4 or later (approximately 2006 onwards)
  • Diesel cars need to be Euro 6 (approximately September 2015 onwards)
  • Electric vehicles are always exempt
  • Plug-in hybrids are generally exempt (most meet Euro 6)
⚠️ Important: Year Alone Is Not Enough
  • The dates above are approximate — some manufacturers adopted new standards earlier or later
  • A car registered in early 2015 could be Euro 5 diesel (not compliant) or Euro 6 (compliant)
  • Always use the registration number check for a definitive answer

3. Quick Rules of Thumb

When you cannot check the registration number immediately, these rules will get you close:

✓ Almost certainly compliant: Any petrol car from 2006 or later. Any diesel car from 2016 or later. Any electric or plug-in hybrid.
✗ Almost certainly NOT compliant: Any diesel car registered before 2015. Any petrol car registered before 2006.

The grey zone: Diesel cars registered between January 2015 and December 2015 are the most uncertain. Some will be Euro 5 (not compliant), others Euro 6 (compliant). For these vehicles, always check using the registration number.

4. Checking Before You Buy a Used Car

If you are browsing used car listings and want to check compliance before committing to a viewing, here is what to do.

  1. Ask the seller for the registration number. Any legitimate seller will provide this — it is not sensitive information and is visible on the car itself.
  2. Run the TfL or GOV.UK check. This takes 30 seconds and is completely free.
  3. Use our Sorted Vehicle Check. Our free Sorted Vehicle Check includes ULEZ and Clean Air Zone compliance alongside MOT history, mileage verification, outstanding finance, write-off status, and more.
Pro Tip: On SortedCars listings, ULEZ and CAZ compliance is shown directly on the vehicle page — no need to run a separate check. Every car listed includes its Euro emission standard and compliance status.

Free Sorted Vehicle Check

ULEZ compliance, MOT history, mileage, finance — all in one report.

5. What If Your Car Is Not Compliant?

If your current car does not meet Clean Air Zone standards, you have several options.

  • Avoid the zone. If you rarely drive into the CAZ area, the simplest option is to plan routes around it. Many sat-nav apps now offer CAZ-avoidance routing.
  • Pay the daily charge. If you only enter the zone occasionally, paying the daily fee may be cheaper than changing your car. London ULEZ is £12.50/day; Birmingham is £8/day.
  • Sell and replace. If you regularly drive in a CAZ, the daily charges add up quickly. Selling your non-compliant car and buying a compliant replacement is usually the most cost-effective long-term solution.
  • Check for scrappage grants. Several councils offer financial help to switch to a compliant vehicle. Check your local council’s website for current schemes.
  • Consider retrofit. Some diesel vehicles can be fitted with approved exhaust treatment systems through the Clean Vehicle Retrofit Accreditation Scheme (CVRAS), though options for private cars are limited.

6. Exemptions You Should Know About

Certain vehicles are exempt from ULEZ and Clean Air Zone charges regardless of their emission standard.

ExemptionDetails
Historic vehiclesVehicles in the “historic” tax class (manufactured before 1 January 1977 for London ULEZ, or over 30 years old and on historic tax for some other zones)
Disabled tax classVehicles registered in the “disabled” tax class are exempt from London ULEZ. Other zones may have different disability exemptions.
Military vehiclesVehicles used for military purposes are generally exempt
Agricultural vehiclesCertain non-road going agricultural vehicles are exempt
Diplomatic vehiclesVehicles with diplomatic immunity status

Important: Exemptions vary between zones. A vehicle that is exempt in London may not be exempt in Birmingham or Glasgow. Always check the specific rules for the zone you plan to enter.

7. The SortedCars Free Vehicle Check

Our Sorted Vehicle Check is designed specifically for used car buyers and includes ULEZ and Clean Air Zone compliance as a standard part of every report. Here is what you get for free:

  • ULEZ/CAZ compliance status — instant confirmation of whether the car passes all UK zones
  • Euro emission standard — the exact standard so you know where you stand
  • Full MOT history — every test, advisory, and failure
  • Mileage verification — checks for clocking across MOT records
  • Outstanding finance — whether someone else has a claim on the car
  • Write-off check — insurance write-off categories (Cat A, B, S, N)
  • Tax and MOT status — current road tax and MOT expiry
Pro Tip: Run a Sorted Vehicle Check on any car before you go to view it. It only takes a minute and could save you from buying a non-compliant car, a clocked car, or a car with outstanding finance.

8. Moving To or Driving Through Clean Air Zones

Common questions from people who are relocating, visiting, or passing through CAZ areas.

I’m moving to London/Birmingham/another CAZ city. What should I do?

Check your car’s compliance before you move. If it is not compliant, factor the cost of upgrading into your moving budget. A non-compliant car in London would cost you £12.50 every single day you drive it — that is over £4,500 per year.

I’m just passing through. Do I still get charged?

Yes. There is no exemption for passing through a zone. If your vehicle is non-compliant and you enter the zone for any reason — even briefly — the daily charge applies. In London, you have until midnight to leave; you are charged once per day, not per entry.

I live inside a CAZ but do not drive every day. Do I still pay?

You are only charged on days you actually drive. If your car is parked and not moved, no charge applies for that day. However, the moment you drive on a public road within the zone, the daily charge is triggered.

What about rental cars and hire cars?

The registered keeper is responsible for the charge, which in the case of a rental would be the hire company. Most major rental companies now only supply ULEZ-compliant vehicles, but always confirm before collecting.

Final Thoughts

Checking ULEZ and Clean Air Zone compliance is one of the most important steps when buying or owning a car in the UK in 2026. The check is free, takes seconds, and could save you thousands in daily charges.

If you are buying a used car, always ask for the registration number upfront and run a compliance check before viewing. Better still, use our free Sorted Vehicle Check to get ULEZ compliance alongside a full vehicle history in one report.

Related reading: ULEZ and Clean Air Zones: The Complete 2026 Guide | Best ULEZ-Compliant Used Cars Under £10,000

Frequently Asked Questions

Yes. If you know the car’s fuel type and approximate year of manufacture, you can estimate compliance. Petrol cars registered from approximately 2006 onwards (Euro 4+) and diesel cars from approximately September 2015 onwards (Euro 6) are generally compliant. However, the most reliable method is to use the registration number with the TfL or GOV.UK checker.
No. Euro 5 diesel vehicles are not ULEZ compliant. Diesel cars must meet Euro 6 standards to pass ULEZ and most other UK Clean Air Zones. Euro 5 diesels were typically registered between 2009 and 2015.
The same Euro emission standards used for London’s ULEZ apply to Clean Air Zones across the UK, including Birmingham, Bristol, Bath, Bradford, Sheffield, Tyneside, and Scottish LEZs. If your car passes the ULEZ check, it will generally be compliant in all UK Clean Air Zones.
It depends on the exact registration date and model. Euro 6 became mandatory for all new cars from September 2015, but some manufacturers introduced Euro 6 diesel engines earlier. The only way to be certain is to check using your registration number on the TfL or GOV.UK checker. Do not rely on the year alone.
In some cases, yes. Certain diesel vehicles can be retrofitted with approved exhaust after-treatment systems that bring them up to Euro 6 equivalent standards. The Clean Vehicle Retrofit Accreditation Scheme (CVRAS) maintains a list of approved solutions. However, retrofit options are limited for private cars and can be expensive. For most people, replacing the vehicle with a compliant one is more practical.

Check Any Car’s Compliance for Free

Our Sorted Vehicle Check includes ULEZ, MOT history, finance, and more.