The U.S. Department of Transportation (DOT) National Highway Traffic Safety Administration (NHTSA) requires that Tire Identification Numbers be a combination of the letters DOT, followed by ten, eleven or twelve letters and/or numbers that identify the manufacturing location, tire size and manufacturer's code, including the week and year the tire was manufactured.

To find out when your tires were manufactured, look at the manufacturer's identification number. The format of the tire identification number changed in the year 2000. If the last three symbols of the tire identification number are digits, the tire was manufactured before the year 2000. If the last four symbols of the tire identification number are digits, the tire was produced during or after the year 2000.



Tires Manufactured before 2000

Locate the last three digits of the tire identification number on the sidewall.

The last digit is the year of the decade that the tire was manufactured. For example, if the four digits are "418," the tire was manufactured in 1998. Three digit codes before year 2000 had no provision to determine which was the decade of manufacture.

Use the first two digits to determine the week of the year in which the tire was manufactured. To do this, simply read the number of weeks specified by the two digits. For example, if the four digits are "418," the tire was manufactured on the forty first week of 1998.

Although Tire Identification Number is required to be branded onto one sidewall of every tire, current regulations also require that DOT and the first digits of the Tire Identification Number must also be branded onto the opposite sidewall. This means that it is possible to see a Tire Identification Number that appears to be incomplete. It requires looking at the tire’s other sidewall to find the entire Tire Identification Number.


Tires Manufactured after 1999

Locate the last four digits of the tire identification number on the sidewall.

The last two digits are the decade and year that the tire was manufactured. For example, if the four digits from the code are "1207," the tire was manufactured in 2007.

Use the first two digits to determine the week of the year in which the tire was manufactured. If the four digits are "1207," the tire was manufactured on the twelfth week of 2007.