Mileage is sometimes a little tricky so make sure to understand the contract you are looking into. Some plans use actual mileage while other plans use additional mileage.
Actual mileage is the reading on your odometer. For example, if your coverage is for five years and 100,000 miles but you already have 50,000 miles on the car, your plan will only cover 50,000 more miles.
Additional miles move from the initial odometer reading on. So if your plan covers five years or an additional 100,000 miles and you already have 50,000 miles on the vehicle, your coverage will expire in five years or once you reach 150,000 miles.
When purchasing a vehicle warranty, make sure to note the way the mileage warranty is worded.