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Buying a Car: How Do You Know a Car’s In-Service Date?

If you’re interested in buying a car with a certified pre-owned (CPO) warranty or with some amount of remaining factory warranty, you’ve probably heard the term “in-service date,” which is also known as the original in-service date or the original sale date. An in-service date is the day a car is sold to the first owner. But why is it so important? And how exactly do you calculate it?

Why Is It So Important?

An in-service date is important because it’s not only the date the car is originally sold, but it’s also the date a car’s warranty begins. And it’s not just the warranty. An in-service date can be used to calculate when other perks begin, such as free scheduled maintenance (if a car includes it), free factory trials of features such as SiriusXM radio and dealer-installed extras such as stolen-vehicle tracking.

So if you’re interested in buying a used car with some warranty life left, it’s obvious why the in-service date is so important: It’s how you calculate when your warranty expires and your repairs are no longer covered by the manufacturer. A simple model year isn’t good enough because it doesn’t tell you everything you need to know. A 2012 car, for example, may have been sold at any point from early 2011 through the end of 2012 — or even later.

An in-service date is also used for calculating most certified pre-owned warranties. While some CPO warranties begin the day a buyer purchases the used car, most start on the day the car was originally sold. In other words, knowing the car’s in-service date can be a huge benefit because it determines exactly how much warranty you’ll get with your certified pre-owned car.

How Do You Calculate It?

Now that you know why the in-service date is so important, you’ll probably be curious how you calculate it. Unfortunately, there’s no simple answer.

The best way to find out a car’s in-service date is to call up your local dealership and find out for sure. If you’re interested in a Kia, for instance, you’ll want to call up a Kia dealership’s service department and ask when the car originally went into service. Most dealerships will have no problem giving you this information over the phone at no charge. If you’re buying a car from a dealer, you should expect this information to be included before the sale is finalized so you know exactly how much warranty you have left.

If you’re negotiating a car deal on a day when a dealership’s service department is closed, you may want to check the car’s AutoCheck or Carfax vehicle-history reports. Both of these reports will give you the car’s original sale date, and while it may not precisely match the dealer’s official figure, it will give you a great idea about when your warranty likely began — and when it’s set to expire.

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