Will your next car cost you £12.50 a day in London?

Clean air zones charge older, more polluting vehicles a daily fee to enter certain city centres. London's ULEZ is the best known, but Birmingham, Bristol, Glasgow, Edinburgh and others now run similar schemes. The rule of thumb: petrol cars need to meet Euro 4 emissions standards (roughly 2006 onwards) and diesel cars need Euro 6 (roughly September 2015 onwards) to avoid the charge. Electric and hydrogen cars are always exempt. It's not a perfect rule: some early-2006 petrol models and some pre-2015 diesels with unusually clean engines fall on the wrong side of the date-based approximation, which is why a proper listing states the confirmed Euro status from the vehicle's own data, not just a guess based on registration date. If you're planning to drive into a clean air zone regularly, check the specific vehicle's Euro status before you buy, not after.