Miles on a highway household's car add up quickly, and a service contract should be sized to the car you actually drive, not the car on the brochure. This guide is for the household that makes long runs at steady speed, often to visit family or to cover a wide working region, and that needs the car to start every morning.

Measure the year, not the odometer

Start with the miles you drive in a typical year. Pull the service records and the odometer readings from the last two visits, subtract, and divide the gap by the days between them. Write the result down. A car that adds a large share of its miles on the interstate reaches its wear points sooner than the odometer alone suggests, because long hours at speed keep the engine, transmission and cooling system working through the same parts. Ask each contract company how it treats high-use vehicles. Some documents set a limit on annual miles, and some say nothing about it. Find out which case applies before you sign.

Check the acceptance mileage against today

Every contract states the mileage at which it will accept the car. Compare that figure with the reading on the odometer the day you apply, not with the reading you expect in six months. A long-trip household can pass a limit within a single season. If the car is already past the line, the contract is not a fit, however well its terms read.

Match the term to the way the car is kept

Ask how long the car will stay with the household. If a move, a job change, or a plan to sell could happen inside the term, read the transfer and cancellation rules first. The exclusionary and listed-parts comparison on this site explains why the way a car is used can change which parts a contract addresses.

Checklist before you compare

  • The annual miles you drive, taken from your own service records
  • How many people drive the car on the long runs, and whether the contract cares who is driving
  • The acceptance mileage in the contract, set against the odometer reading on the day you apply
  • Whether high-use or annual-mileage limits appear anywhere in the document
  • How the contract treats the car if it is sold or the household moves