Biketoworkday is supported by its audience. When you buy through our links, we may earn an affiliate commission. Learn more

What Year is My Trek Bike by Serial Number?

Written by Gary Johnson / Fact checked by Henry Speciale

what year is my trek bike by serial number

Serial numbers can be found on bicycles and components. These contain information but companies like Trek don’t readily offer a decoder. What if we’d like to know what year is my Trek bike by serial number?

Find the last letter in the serial number; this represents its year of production. D stands for 2009, while R is for 2021, and you can count what note corresponds to what year while skipping letters I and O.

Keep reading to learn more.

What Year is My Trek Bike and Other Information From a Serial Number


Trek bicycle serial numbers contain some helpful information, and one of these is the year a specific bike was made. If your unit has a 13-character serial, all you have to do is look at the last character. This letter will correspond with a specific year.

D stands for 2009, and R is for 2021; you can count forward or backward to identify what other letters stand for. However, the letters I and O have been skipped to avoid confusion with numbers 0 and 1.

Manufacturing year The last letter
2021 R
2020 Q
2019 P
2018 N
2017 M
2016 L
2015 K
2014 J
2013 H
2012 G
2011 F
2010 E
2009 D

Based on the compiled information, units produced in 2023 should have the letter T as their last character, but this is just an inference. The same goes for A, B, and C; these have yet to be included in compiled information.

On the other hand, vintage Trek serial numbers use a different system which is apparent due to being only 6 or 7 characters long. Learn more about vintage serials below.

What is a Serial Number and Why Use It?


A serial number is a series of characters made up of numbers, letters, or a combination of both that serves as a unique identifier for specific products. These are usually printed somewhere on the body of the product it marks.

Various information may be included in a serial number, including its production date and where it was produced. Some items also include product specifications such as size. However, serial numbers are often difficult to understand and need some sort of decoding knowledge to make sense of.

For bicycles, serial numbers are important to register for warranty and other services. They also serve as insurance in case of theft.

1. How to Find the Serial Number Location

The serial number on Trek bicycles is usually found at the same spot, whether it’s a modern bike or one that is vintage.

To check serial number on bike, turn it over and look at the underside of the frame below the bracket. This location is not exclusive to Trek, and many other bicycles have their serial here as well.

Some vintage bicycles have the print in other locations, such as under the cable guide at the bottom of the shell or the seat tube’s lower end.

2. Serial number on Trek bike and understanding the format


For your Trek bike serial number decode it by looking at the sequence of characters, the order is important. The series is made up of 13 characters using both letters and numbers. Below is a sample serial that is not from any specific bicycle.

Ex: WTU 123 AB 4567 R

The serial begins with WTU and any modern Trek bike serial number format begins with the same three letters. The next sequence is a series of three numbers corresponding to the specific day a bicycle is produced. This means that the sample code indicates that it was built on the 123rd day of that year.

The next couple of letters is its manufacturing plant code. However, we do not know how to identify which facility is represented by these codes. All we can tell is if two bikes came from the same factory.

The second numerical sequence is believed to be the bicycle’s ID code and is probably used to differentiate an individual bike from all others. Finally, the lone letter at the end represents its year of production, as we’ve already tackled above.

How to Read Serial Numbers on Vintage Trek Bicycles


Trek bikes have been made for a long time and a vintage Trek serial number works differently from modern ones. They do not begin with WTU and are much shorter. However, they are hard to decode because the format changed multiple times through the years.

Bicycles produced from 1976 to 1980 have been well-documented and this serial system is well-understood. They are made up of seven characters beginning with a letter and ending with two numbers using an LNLNLNN format where L stands for a letter and N for a number.

The first letter represents the model, the first number is its frame size, the second letter goes from A to L each representing a month, and the second number is the last digit of the year of production. The last three characters are the run designation followed by the frame number within that specified run.

Below is a chart for the first letter and the first number of serials used during the period.

First Letter (model) First Number (frame size)
Letter Model Number Size
A 310 1 19.75 in
B TX200 2 21 in
C TX300 3 22.5 in
D 530 4 24 in
E TX500 5 25.5 in
F 510 6 57.5 cm
G TX700/TX770 7 59 cm
H 710 9 63.5 cm
I 730 *6, 7, and 9 represent custom sizes
J TX900    
K 910    
L 930    
M 412/414    
N 610/613/614    
O 950    

Bikes produced in other years make use of other systems, but the use of the seven-character serial reached up to around 1999, although six-character serials were also used at some point.

If your vintage bike is not covered by the formats we covered here, you can check out the Trek bicycle serial number chart resource here. Unfortunately, information for specific batches is still lacking, but they also have valuable information for cross-referencing, such as the colors of the models by year.

Frequently Asked Questions


How do I register my Trek bike?

Head to Trek’s official bike registration page; you’ll find an input field where you can type in your serial number. You can also search bike’s serial number on this page.

Type in the serial without any spaces in between to register your bicycle into Trek’s official database. Read about where the serial number is located above.

Why is it important to register?

The two main reasons to register are to receive various support from Trek and for security in case of loss or theft. While Trek does not clarify how they can help, registering helps, so you may be able to contact them for help in such situations via

Registering the bike will also help prove ownership in case the bicycle is taken into police custody. Warranty is only available for registered units, and a Trek mountain bike could use it if you frequently ride rough terrain.

As for support, you will be able to obtain valuable information via model lookup only if you are registered. They also mention that older models can still be registered.

Why does my bike not have a serial number?

Some vintage bikes do not have serial numbers at all. These were some that were produced from 1976 to the 1980s. Other early models have the number elsewhere, such as beneath the cable guide near the bracket shell.

It’s also possible that the print has worn down over time or that the frame was repainted, resulting in the serial no longer being visible.


What year is my Trek bike by serial number? Now you know where is the serial number on a Trek bike and how to read it. After reading this, make sure to register your bicycle if you haven’t already.

Are you familiar with serial numbers for other bicycle brands? Are they different in how they work and are they as useful as those from Trek’s bikes? Tell us about them in the comments section below.

Always ride safely.

5/5 - (3 votes)