Tire Date Code: How to Read the DOT Number on a Tire

Where the tire date code lives

Every tire sold in the US carries a tire identification number, or TIN. It starts with the letters DOT and sits on the sidewall near the rim. The date is hiding at the very end of it.

The catch: the full number isn't always on the side you can see. NHTSA tells drivers to look on both sides of the tire, because the TIN may not be on both. On a car parked in a tight Brickell garage, that usually means a flashlight and a look at the inboard sidewall, the one facing under the car.

What you're looking for:

• The letters DOT, often in a slightly raised oval or box.
• A string of letters and numbers after it.
• A group of four digits at the end, sometimes set apart in its own oval.

If you find DOT followed by a short code that stops without four digits, you're probably on the partial side. Check the other sidewall.

Reading the four digits

Those last four digits are the build date. Per NHTSA and Goodyear, the first two are the week of the year and the last two are the year.

Week 01 is the first full week of the year, so a code starting with 01 means early January, not New Year's Day exactly. You don't need to be more precise than the month to use the date well.

Type yours into the reader below. It highlights the date digits and places the tire on a timeline.

Three-digit codes: tires built before 2000

Before 2000, the date was only three digits. Goodyear explains the format: the first two digits are still the week, but the last digit is only the year within the decade. A code ending in 317 could mean week 31 of 1997, 1987 or 1977. The decade isn't shown.

In practice, the decade barely matters. A three-digit date code means the tire is more than 25 years old. If you find one on a car, a classic, a trailer or a spare that came with a used vehicle, don't just check the tread. Have it inspected, and plan on a conversation about replacing it.

The rest of the DOT number

The characters between "DOT" and the date aren't random. General Tire breaks a DOT serial number into these parts:

1. Plant code. Which factory built the tire.
2. Tire size code. A manufacturer's code for the size.
3. Tire type code. An optional group the manufacturer uses for its own tracking.
4. Date code. The four digits covered above.

The format got more uniform in 2015. NHTSA's final rule that year:

• expanded the plant code from two symbols to three for new tires, because two-symbol codes had run out;
• standardized a new tire's TIN at 13 symbols;
• gave most manufacturers until 2025 before the new format became mandatory.

So on the road today you'll see both lengths. A shorter TIN with a two-symbol plant code is most likely the older format, not a mistake. Either way, the last four digits are still the date.

Using the full DOT number for a recall check

This is where the whole number earns its keep. The date alone tells you age. The full TIN tells a recall database which tires you have.

Two free lookups:

• USTMA Tire Recall Lookup. Enter the full TIN. It covers recalls on tires made by U.S. Tire Manufacturers Association members from 2000 onward. If a tire matches, it gives you the manufacturer's contact for the remedy.
• NHTSA recalls. Search by tire brand and tire line. Use this for brands outside the USTMA membership, or if you're not sure who made the tire.

Better still, get ahead of recalls. Federal rules set up a tire registration program so manufacturers can reach the people who bought their tires. When you buy new tires, register them with the manufacturer using the TIN. Our guide to tire recalls and registration walks through it.

What the date tells you, and what it doesn't

A date code is a birth certificate, not a health report.

• It tells you age. NHTSA's tire buyers' FAQ says to check this date when you buy, and to know your vehicle manufacturer's recommended replacement timeframe for tires.
• It doesn't tell you condition. Two tires built the same week can age very differently. One sat in a climate-controlled warehouse; the other baked on a car parked outside all summer.
• It doesn't set a legal deadline. Age guidance comes from vehicle and tire manufacturers, and it varies. We lay it out side by side in How Old Is Too Old for Tires?.

If the tread looks deep but the date is old, don't let the tread talk you out of a closer look. Cracking in the sidewall or between tread blocks is a reason to have it inspected.

A 60-second routine

1. Find DOT on each tire, spare included. Check both sidewalls.
2. Write down the last four digits for each position.
3. Save one full TIN per tire, or snap a photo of it.
4. Run the full TIN through the USTMA lookup.
5. Enter the dates in the Do I Need Tires Yet? check, alongside your tread depth.

Buying tires online? Check the dates when the set arrives, before anything gets mounted. Our post on getting online tires installed in Broward covers that handoff.

Questions about a code you can't read? Call Extreme Tires in Sunrise at (954) 773-1896 and ask.