Reference
The tire identification number
New and retreaded tires sold in the US carry a code on the sidewall, often called the DOT code. It tells you which plant made the tire and the week and year it was made, and it is how a tire recall finds the tires it covers. Here is how to read each part, how tire recalls work, and how the code differs from a vehicle's VIN.
The short answer
The tire identification number, or TIN, is set by NHTSA's rule in 49 CFR Part 574. On a new tire it is 13 characters long and has three groups: a plant code, a manufacturer's code and a date code. The date code is the last four digits: the first two are the week the tire was made and the last two are the year.
Part 574 says its purpose is to help notify purchasers of defective or nonconforming tires, which is why it also sets up tire registration. A TIN is not a serial number for one tire, and it is not part of your car's VIN. RunThatVIN decodes vehicle VINs and lists vehicle recalls by year, make and model; it does not decode tire codes or look up tire recalls.
Where to find it
The TIN is on the sidewall, with the DOT symbol, which certifies that the tire conforms to an applicable Federal Motor Vehicle Safety Standard. Under 49 CFR 574.5, a manufacturer must put the TIN on one sidewall of each new tire. NHTSA's advice is to look on both sides, because the TIN may not be on both, and its 2019 Electronic Tire Identification Study notes that a TIN on the inward-facing sidewall is harder to reach and record. A retreaded tire is also marked with the letter R, which is not part of the TIN.
What each part means
Section 574.5 allows only the digits 0 to 9 and the capital letters other than G, I, O, Q, S and Z. A new tire's TIN reads in this order:
| Group | Symbols | What it holds |
|---|---|---|
| Plant code | 3 | The factory, from a code NHTSA assigns on request |
| Manufacturer's code | 6 | A descriptive code for the tire, or one identifying the brand name owner |
| Date code | 4 | The week and year of manufacture |
The manufacturer's code means different things from one manufacturer to the next, so you can't decode it from the rule alone. The manufacturer must keep a record of each code and its meaning and give it to NHTSA on request. A retreaded tire has a 7-symbol TIN: the plant code and the date code only.
The older format
NHTSA's 2015 final rule explained that the agency had used up all 900 two-symbol plant codes, so it moved to three-symbol codes and a 13-symbol TIN. Plants with a two-symbol code could keep using it until April 13, 2025, under the old format: a two-symbol plant code, a group of no more than two symbols for the tire size, an optional descriptive code of no more than four symbols, and the same four-digit date code. Either way, the date code comes last.
How to read the week and year
Section 574.5 says the first two digits of the date code identify the week of the year and the last two are the last two digits of the year. Three details in the rule matter:
- Week 01 is the first full calendar week of the year.
- Each week runs from Sunday through the following Saturday.
- The final week of a year may include up to six days of the following year.
So a date code of 2524 means the 25th week of 2024. The rule's own example is 0109, the first full calendar week of 2009, and NHTSA's tire page gives 0308 as the third week of 2008. The code gives you a week, not a day.
What the date tells you
NHTSA recommends checking this date when you buy tires, and says you cannot detect tire aging simply by looking at your tires. It reports that some vehicle and tire manufacturers recommend replacing tires that are six to 10 years old, regardless of treadwear. NHTSA's new tire handbook adds that service life recommendations vary by vehicle and tire manufacturer, and points owners to their owner's manual.
How tire recalls work
Tires are recalled under the same federal law as vehicles; see how vehicle recalls work for the overall process. What differs is how the tires and owners are found, and how the free remedy is limited.
Finding the tires
A TIN is not unique. NHTSA's Electronic Tire Identification Study puts it plainly: all tires of the same make, model and size made in the same factory in the same calendar week have the same TIN. So a tire recall report filed with NHTSA lists the tire line and size, plus TIN fields for the plant code, size code, optional code and a beginning and ending date code.
Finding the owners
Part 574 relies on registration. Under 49 CFR 574.8, a tire dealer not owned or controlled by a tire manufacturer or brand name owner must, at no charge to you, either give you a registration form filled in with the full TIN and the dealer's name and address, or send your name, address and TIN to the manufacturer itself, on paper or electronically, within 30 days. Other dealers must send the information to the manufacturer. Manufacturers keep the records for at least five years. NHTSA's new tire handbook says manufacturers rely on registration to alert customers to a recall, and tells buyers to ask the retailer whether it registered them.
The free remedy, and its limits
Under 49 U.S.C. 30120, a recalled tire may be repaired, replaced with an identical or reasonably equivalent tire, or refunded. Two limits apply:
- A 5-year age limit. The free remedy is not required if the tire, including an original equipment tire, was bought by its first purchaser more than 5 calendar years before the recall notice or NHTSA order, whichever is earlier. For vehicles the limit is 15 years.
- A 180-day window. The owner must present the tire within 180 days after receiving the recall notice or, if the manufacturer is replacing tires, after being told a replacement is available, whichever is later.
The same law bars selling or leasing a recalled tire for use on a vehicle unless the defect has been remedied. For the practical side, see getting a recall repaired.
How to check a tire for a recall
- Write down the whole TIN, with the brand, tire line and size. NHTSA's handbook notes the TIN is also on your receipt or registration form.
- Search NHTSA's recall site using its tire option. NHTSA says a tire search gives general results for recalls, investigations, complaints and manufacturer communications, so read any recall that matches your brand and tire line.
- Compare the codes. If the recall's tire line, size and plant code match your tire and it was made in the weeks the recall lists, contact the manufacturer or a dealer to confirm.
- Register and sign up. Register the tires if your dealer did not. NHTSA also offers recall alerts by email and through its SaferCar app.
NHTSA describes its VIN search in terms of vehicles, not tires, so don't count on a VIN recall search to cover the tires.
How a TIN differs from a VIN
| TIN | VIN | |
|---|---|---|
| Rule | 49 CFR Part 574 | 49 CFR Part 565 |
| Length | 13 symbols (7 on a retread) | 17 characters |
| Identifies | A batch: one plant, one tire type, one week | One vehicle |
| Date | Week and year of manufacture | Model year |
Under 49 CFR 565.13, no two vehicles made within a 60-year period beginning with the 1980 model year may share a VIN, and under 565.15 its characters give the manufacturer, vehicle attributes, a check digit, the model year, the plant and a production sequence number. Our guide on how to read a VIN covers each position. You can decode a VIN here to see what the manufacturer built, but for the tires on it, read the sidewall.
Quick answers
How do I read the date code on a tire?
The date code is the last four digits of the tire identification number. The first two give the week of manufacture and the last two give the year, so a date code of 2524 means the 25th week of 2024. Week 01 is the first full calendar week of the year, and each week runs Sunday through Saturday.
Where is the DOT code on a tire?
On the sidewall, with the DOT symbol. Federal rules require the full tire identification number on one sidewall of a new tire, and NHTSA says to look on both sides because the number may not be on both.
How do I check if my tires are recalled?
Write down the full tire identification number with the brand, tire line and size, then search NHTSA's recall site using its tire option. Compare the tire line, size, plant code and date codes in any matching recall with your tire. Registering your tires lets the manufacturer reach you if they are recalled.
Can RunThatVIN decode a tire code or look up tire recalls?
No. RunThatVIN decodes vehicle VINs and lists vehicle recalls by year, make and model. It does not decode tire identification numbers or search tire recalls. For tires, use NHTSA's recall search.
Sources
- 49 CFR Part 574, Tire identification and recordkeeping (eCFR), including 574.5 and 574.8
- NHTSA, Tire Identification and Recordkeeping, final rule, 80 FR (April 13, 2015)
- 49 U.S.C. 30120, Remedies for defects and noncompliance
- 49 CFR 565.13, General requirements for the VIN (eCFR)
- 49 CFR 565.15, Content requirements for the VIN (eCFR)
- NHTSA, Tires
- NHTSA, Check for Recalls: Vehicle, Car Seat, Tire, Equipment
- NHTSA, Congratulations on Your New Tire Purchase (PDF)
- NHTSA, Tire Buyers' FAQ: What You Should Know and Ask (PDF)
- NHTSA, Report to Congress: Electronic Tire Identification Study (March 2019, PDF)
- NHTSA, Part 573 Safety Recall Report 23T-009 (an example of how a tire recall identifies tires)