---
title: "Fatbike frame number: where to find it and what it’s used for"
description: "Where to find a fatbike frame number and why it matters for theft prevention and buying secondhand. Netherlands's #1 bike registration platform!"
canonical: "https://www.bikebaze.nl/en/blog/fatbike-frame-number-where-to-find-it-and-what-its-used-for"
published: "2025-12-29T09:50:01.000Z"
---

# Fatbike frame number: where to find it and what it’s used for

A fatbike's frame number is usually under the bottom bracket, on the down tube, or near the motor or battery on electric models. You use it to check whether a bike is stolen, register it, file a theft report and prove ownership. If the number is missing on a used fatbike, walk away.

**Direct answer:** The frame number of a fatbike is usually located under the bottom bracket or on the frame near the motor. It is used to prevent theft, prove ownership and register the bike.

## Why is the frame number especially important for fatbikes?

Fatbikes are popular and relatively expensive, which makes them attractive targets for bike theft and illegal resale.

## Where is the frame number on a fatbike?

On most fatbikes, the frame number can be found:

- Under the bottom bracket
- On the down tube of the frame
- On electric fatbikes: near the motor or under the battery

In some cases, the number can be difficult to spot.

## What can you do with a frame number?

A frame number allows you to:

- Check if a fatbike is stolen
- Register the fatbike
- File a theft report
- Prove ownership

## Tip when buying secondhand

If the frame number is missing or unreadable, do not buy the fatbike. This is often a warning sign.