A service is preventative — a mechanic goes through your car on a schedule and catches things before they turn into an MOT failure, a breakdown, or a much bigger bill. There's no pass or fail. Garages generally offer it in three tiers, and which one you need depends on how long it's been and how far you've driven since the last one.
The three tiers
Each one builds on the last — a full service includes everything in an interim, a major includes everything in a full.
Interim service
- Engine oil and oil filter change
- Fluid level checks — coolant, brake, washer
- Visual brake and tyre inspection
- Lights, battery and belts checked
Full service
Everything in an interim, plus:
- Air filter change
- More thorough brake inspection (often with wheels off)
- Suspension and steering checks
- Exhaust and fluid leak inspection
Major service
Everything in a full service, plus:
- Spark plug replacement
- Fuel filter replacement
- Cabin/pollen filter change
- The most thorough overall inspection available
On cost
Prices vary a lot by garage, location and vehicle — an interim on a small hatchback and a major on a larger diesel aren't comparable jobs. It's worth getting quotes from two or three local garages rather than assuming a fixed figure; independents are often notably cheaper than main dealers without affecting your warranty.
Working out when yours is due
Check the service book or reminder display
Most cars log this automatically, or it's stamped in a physical book that came with the car.
Whichever comes first wins
If you're at 12 months but only 4,000 miles, you're still due — time and mileage are both triggers, not just one.
High mileage? Add an interim in between
Motorway commuters and high-mileage drivers often add an interim service between full services rather than stretching to 12,000 miles on one set of oil.
Bought the car used?
Check the stamped history for gaps — a missing stamp is usually a missed service, not just a missed record.
Quick reminder — this isn't your MOT
A service is maintenance you choose to have done. An MOT is a legal pass/fail test you're required to have annually once the car turns three. A fresh service the week before your MOT genuinely improves your odds of passing — but it doesn't replace the test itself.
Service tiers and typical intervals reflect common UK industry practice as described by the RAC and AA. Servicing is not a DVSA-regulated or legally mandated process — always check your own vehicle's manufacturer schedule, which takes priority over any general guidance here.