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

Where Is the Serial Number on a Bike? – 4 Popular Location

Written by Gary Johnson / Fact checked by Henry Speciale

where is the serial number on a bike

We can find serial numbers on many items, such as electronics, and they’re even used on vehicles like cars or boats. But where is the serial number on a bike?

You can find bikes serial number on the frame, usually somewhere around the bottom bracket. Let’s take a look at the usual spots on bike frame where we can find this info, and a few other important things to know.

Keep reading to learn more.

Bike Serial Number Meaning


Serial numbers are unique numerical sequences that serve as identification for each bicycle. Through them, two bikes with the same make and model can be differentiated from one another. They are also referred to as the bike frame number.

These work similarly to the Vehicle ID Number (VIN) found on cars and can be used for protection against theft. In case it is stolen, a bicycle can be tracked by authorities and recovered.

Without this, it will be hard to establish ownership of a bike that you think is yours; and the serial code is also needed when filing an insurance claim.

Bicycle serial numbers are usually six to ten digits long and may vary depending on each manufacturer. Even the location of the serial may differ depending on the manufacturer, with certain companies favoring specific areas on the bike. BMX bikes, for example, usually have the number on their dropout.

Within the serial code, certain types of information are usually included, such as the production year and month along with the specific id of that frame. The system may also vary for each company.

Where to Find Serial Numbers on a Frame


There are a few common spots to check first when trying to find a serial number on a bike. Checking these four usually yields results.

1. Bottom bracket / below or above the crank

This is the most common bike serial number location, especially for modern one. The bottom bracket is where the crank arms spin around. You’re likely to find the number under this.

Above the bracket is another good spot to check, though it’s not used as often.

2. Chain stays (either side)

These are two thinner tubes, one on each side of the rear wheel running from it to the bottom bracket; the id may be on one of these. You’ll find the chain along with one of these tubes.

The seat stays look similar and connect to the rear wheel as well, but they run upward to the seat instead.

It’s also a good idea to check the rear dropout where the chain stays and seat stays are joined as the serial can sometimes be here as well.

3. Seat tube

This is the main tube where the seat is connected. The number will usually be near the crank, though be sure to check the whole length.

4. Headset or head tube

The head tube is the slot at the front of the frame with the handlebars above it, while the headset is what’s slotted in the head tube, connecting the frame and the wheel fork. The serial number can be on one of these as well.

Making Use of Serial Numbers

After finding the serial number on a bicycle, it is important to keep this in your possession as it is needed to track your frame. Save a copy or two and make sure it is something you’ll be able to get hold of in case of loss or theft.

You need to register the code to enable authorities to look up bicycle serial number assigned to your bike. Registration can be done with online registries such as BikeIndex or even local authorities.

In case your bike doesn’t have a serial number, there are ways to mark it for identification. 529 Garage, formerly Project 529, is a group that provides a means of personalizing bikes for registration using a sticker.


Now that you know where is the serial number on a bike, don’t forget to check bike serial number on your bicycle and register it. It’s a very useful method for protecting yourself against theft, so make good use of it.

If you have any comments or if you’d like to share any suggestions and experiences regarding bike serial numbers, please drop us a message in the section below. We’d love to hear from you.

Always ride safely.

5/5 - (2 votes)