Petrol cars typically require servicing every 10,000 to 12,000 miles or once a year, whichever comes first. Many drivers get their vehicle serviced every six months, especially if they drive a lot, once before their MOT and once as a six-month interim check-up.
Diesel engines endure compression and soot build-up at a higher rate than petrol engines, so they need servicing more frequently. Aim for every 8,000 to 10,000 miles or once a year, whichever is sooner.
Weirdly, cars that complete more urban, stop-start, short trips frequently tend to need servicing more often than cars that have longer regular journeys with less traffic. As well as this, there are a few other factors: