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Did you know that every vehicle comes with a unique serial number? The 17-digit Vehicle Identification Number (VIN) is like a secret password to a car’s past. It can unlock information on where it’s been, what it’s done, and how it’s been used – and sometimes you can check a vehicle’s history for free.

The VIN is used to locate your vehicle history report, which tells you whether the vehicle has been stolen and recovered, or damaged in an accident, flood, or fire. The report also shows how far it’s been driven and who’s owned it, as well as its title branding, which revealswhether the car has been deemed damaged in relation to its value. Gettinga vehicle history report is especially important when you’re shopping for a used car. Learning about the vehicle’s past before you plunk down your money can help you avoid a bad purchase.

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“A VIN check is imperative for used car shoppers, as it will let you know if the car has a salvaged or branded title – that is, if the car has been totaled by an insurance company due to extensive damage from an accident, flood, or other event,” said Jamie Page Deaton, managing editor of U.S. News Best Cars.  “Avoiding cars with salvage or branded titles will save consumers some major ownership headaches.”

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Most services charge a fee for a vehicle history report, but sometimes you can obtain limited information about your vehicle without paying for it. “Free VIN checks will get you the major red flags, like a salvaged title,” Deaton said, “but paying for a VIN can get you more details, like how many owners the car has had.” 

The federal government offers VIN checks, free of charge, through the National Insurance Crime Bureau, which provides data on the vehicle’s current state of title and last title date, brand history, odometer reading, total loss history, and salvage history. The VINCheck tool permits five searches within a 24-hour period per IP address. Note that records can take up to six months to appear in the federal database and only show up if the event was recorded by an insurance company. Meanwhile, you can plug the VIN into the National Highway Traffic Safety Administration’s database to find out if a vehicle has been recalled.

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The government reports are less detailed than those you would find through a paid service. You’ll have to buy a report from a third-party, such as Carfax or AutoCheck, if you want comprehensive information on recalls and repairs. A detailed report will include a description and overall evaluation of the vehicle, along with dates and locations for when it was serviced and sold. It will also reveal if the car has been registered in numerous states by previous owners, or recalled, or repurchased by the manufacturer under the lemon law.

CarFax, a U.S. News & World Report partner, offers free VIN checks in many of our used car listings. It also sells longer reports through its website – $39.99 for a single report and $59.99 for a bundle of five – that include more details than competitors, such as service department records. AutoCheck, a competitor service owned by Experian, tells you a vehicle’s make, model, and country of origin based on the VIN. Its paid reports generate a numerical score for the vehicle so that you can compare it to similar ones built that year. You can buy an AutoCheck report on a single vehicle for $24.99, or pay $49.99 to access 25 reports within 21 days.

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VehicleHistory.com provides the most comprehensive free VIN check. Its website generates detailed information on a vehicle’s performance, inspections, specifications, safety ratings, warranty, and a multitude of other topics. It will tell you where the vehicle has been listed for sale, its list price and sale price, and the status of its parts and components.

Another website that offers a VIN check free of charge is VINCheckPro. Enter your VIN into the database, and the website will tell you the age, make, model, engine type, and country of origin for your vehicle, as well as whether a recall has been issued. VINCheckPro will also assign the vehicle a score for safety and environmental friendliness. However, you’ll have to pay for more detailed information such as title status, accident history, and odometer readings. A single report costs $9.95, and a package of five runs $15.95.

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Remember that if you’re scoping out a vehicle for sale, you can sometimes obtain a free VIN check simply by asking. Most dealerships have subscriptions to Carfax and other services that provide vehicle history reports, and your sales associate can obtain the report for you. An independent seller may also be willing to throw in a VIN check for free if it means he or she will be likelier to sell the car.