When / where do I have to pay to use a vehicle in a Clean Air Zone?

Payment of the charge must be made for each day a non-compliant vehicle is used within a Clean Air Zone, either up to 6 days in advance of, or by 11.59pm on the 6th day after, using the vehicle in the zone.

Charges apply daily, 7 days a week, 365 days a year and from midnight to midnight (for example, 2 x daily charges should be paid for a vehicle entering a Clean Air Zone at 11pm and leaving at 1am the following morning.

Payment should be made at the GOV.UK Drive in a Clean Air Zone service, not to the local authority directly, though a number of Clean Air Zone exemptions and discounts apply, which may require a different method of payment.