What is a certified pre-owned warranty?

A certified pre-owned (CPO) warranty is extra coverage that comes with a used vehicle that has passed a manufacturer or dealer certification inspection. Manufacturer CPO programs typically extend powertrain coverage, add a limited comprehensive warranty, and may include roadside assistance. Dealer-certified programs can be very different and are backed by the dealer or a third party rather than the automaker. Ask which kind of certification it is, get the warranty terms in writing, and note whether a deductible applies.