Scotland
Required standards for vehicles
Petrol vehicles must meet Euro 4, diesel vehicles Euro 6 (or face penalties).
Charges for non-compliant vehicles
No daily charges (non-compliant vehicles are simply fined rather than charged).
Fines for non-payment
£60 fine (reduced to £30 if paid within 14 days) for a non-compliant vehicle, doubling on each subsequent offense up to £480 max.
Important information
All non-compliant vehicles (including private cars) are not allowed to enter without penalty – there is no daily charge option.