How to check a car against clean air and low emission zones

01

Charge, fine or nothing: what kind of zone is it?

Three systems cover the UK's emission zones, and each treats a car that misses the standard in its own way. England's clean air zones charge a fee for each day. Scotland's low emission zones are meant to keep such cars out, and penalise those that enter. London's Ultra Low Emission Zone, run by TfL, charges a daily fee across every borough and the City of London.

Most English zones leave private cars alone, so the first question is not whether a zone exists on your route, but whether its rules reach a car at all.

02

Which English clean air zones charge a car?

GOV.UK gives each zone a class, and the class decides who pays. Class A: buses, coaches, taxis and private hire vehicles. Class B adds heavy goods vehicles, Class C adds vans and minibuses, and Class D adds cars, with the council free to include motorcycles. Private cars pay only in Class D zones.

Greater Manchester no longer appears on GOV.UK's list: its review ended with agreement to a plan without charges. Birmingham's charge is set by its council, so look it up on the council's clean air zone site before you travel.

03

How and when do you pay an English zone charge?

A charging zone never switches off. GOV.UK says the English zones operate at every hour of every day of the year, and one charge covers a day from midnight to midnight. Payment opens 6 days before a trip and closes at 11:59pm on the sixth day after it.

Nobody will remind you. Bristol City Council says drivers are not notified after entering its zone and that paying is their responsibility. Miss the deadline there and a £120 penalty charge notice follows, reduced to £60 if paid within 14 days, with the daily charge still owed on top.

04

Scotland's low emission zones: a fine, not a fee

Aberdeen, Dundee, Edinburgh and Glasgow each have a low emission zone in the city centre. The Scottish Government's mygov.scot site says they operate around the clock, every day, public holidays such as Christmas Day included, and that cameras reading number plates check the vehicles going in.

No fee buys entry. A car that misses the standard and is not exempt risks a penalty charge notice, and mygov.scot says paying in advance to avoid one is not possible. Its scale of penalties:

• £60 for a first penalty, halved to £30 if paid within 14 days;
• double the previous amount for each further entry by the same car into the same zone within 90 days;
• a ceiling of £480 for cars and light goods vehicles;
• back to £60 once 90 days pass after the last penalty.

A car can collect no more than one penalty per zone in a single day. A challenge goes first to the council that issued the notice; after a rejection, the next step is an appeal to the General Regulatory Chamber of the First-tier Tribunal for Scotland.

05

What standard must a car meet, and who is exempt?

For cars, the bar is the same in England's charging zones, in Scotland and in London: petrol cars need Euro 4 and diesel cars Euro 6. These are the European emissions standards a car was approved to, which is a different thing from the CO2 figure behind most vehicle tax.

• Fully electric cars: outside Scotland's zone restrictions, and covered in England by GOV.UK's national exemption for ultra low emission vehicles.
• Hybrids: mygov.scot gives them no special status, so a hybrid is held to the petrol or diesel standard, whichever its engine burns. Put one through the checker before driving in.
• Historic vehicles: on GOV.UK's national exemption list for England. In Scotland the exemption covers vehicles of historic interest: at least 30 years since they were built or first registered, out of production, kept original and not substantially changed. They are recognised automatically.
• Disabled drivers and passengers: England exempts the disabled and disabled passenger tax classes. In Scotland, a vehicle carrying a Blue Badge holder can be exempt, but the exemption has to be registered if the car misses the standard, or a penalty may follow.

Exemptions do not come with the car. A change of owner or of use can leave a previously exempt vehicle non-compliant, mygov.scot warns.

06

The right low emission zone checker for each area

Each official checker works from the registration, and the English and Scottish ones cannot check a car registered outside the UK:

Think a Scottish result is wrong? Before driving in, write to the Scottish Government's low emission zone team, giving the owner's name and address and the car's registration, make, model and colour. Once a penalty has arrived, the council that issued it is the one to contact.

07

Finding the Euro standard a car was built to

GOV.UK points to two places: the vehicle log book and the manufacturer. Its vehicle enquiry service also lists a car's emissions, including the CO2 figure, the real driving emissions level and the European status, where the DVLA holds them.

Our free look-up on the car check home page gives the fuel type, the CO2 figure and the month of first registration, which narrows things down. For a car close to the line, though, the zone's own checker is the one that settles it.

08

Five steps for a clean air zone car check when buying

1. List the zones you will really drive in: home, work, family, regular trips.
2. Before the viewing, enter the registration in each of those zones' checkers.
3. Check a van even in a zone that ignores cars, because Class C zones charge vans.
4. Ignore any exemption the seller has: it may lapse when you become the keeper.
5. Put a figure on it: daily charges on every trip make a non-compliant car dearer to run than a compliant one.

For the yearly tax side of emissions, see what road tax costs.

London's own rules, from the year guide to the penalty, are in ULEZ compliant cars.