Most modern gasoline cars (post-2006), all electric vehicles (EVs), and the latest diesel vehicles (Euro 6 standard for most zones) can drive in a Clean Air Zone (CAZ) without incurring a charge. The key factor is your vehicle's Euro emission standard, which is a classification system for engine pollutants. To be certain, you must check your vehicle's registration number on the official government website for the specific zone you plan to enter, as rules vary by city.
The simplest way to guarantee compliance is to drive a zero-emission vehicle like a battery electric vehicle (BEV) or hydrogen fuel cell vehicle. These are exempt from all charges. For gasoline (petrol) cars, most models registered after January 2006 (generally meeting Euro 4 standards) are exempt. The most complex rules apply to diesel vehicles. Typically, only diesel vans and cars that meet the Euro 6 standard (manufactured from around September 2015 onwards) are exempt from daily fees.
It's not just about cars. Larger vehicles like buses, coaches, and heavy goods vehicles (HGVs) face stricter rules, often requiring a minimum of Euro VI. Below is a general guideline for passenger cars, but always verify online.
| Vehicle Type | Minimum Emission Standard for CAZ Exemption (Typical) | Key Pollutants Regulated | Approximate Year of Widespread Compliance |
|---|
| Battery Electric Vehicle (BEV) | Zero Emissions | N/A (No tailpipe emissions) | N/A |
| Plug-in Hybrid Electric Vehicle (PHEV) | Varies (Must have zero-emission capability) | Nitrogen Oxides (NOx), Particulate Matter (PM) | Varies by model |
| Gasoline (Petrol) Car | Euro 4 | Nitrogen Oxides (NOx), Hydrocarbons (HC) | January 2006 onwards |
| Diesel Car | Euro 6 | Nitrogen Oxides (NOx), Particulate Matter (PM) | September 2015 onwards |
| Diesel Van (e.g., Transit) | Euro 6 | Nitrogen Oxides (NOx), Particulate Matter (PM) | September 2016 onwards |
The best practice is to always plan your route. If you're driving a non-compliant vehicle, you may be able to pay a daily charge online, but this can be expensive for regular travel. For older cars, a retrofit emission system might be an option, though this is often costly.
