Decathlon bikes can use different serial-number locations by model. For connected Decathlon e-bikes, the serial number is a 10-character code made from letters and numbers. On some models, Decathlon says the serial number is on the seat tube or seat post. On the Cargo F900E, it is on the frame to the left of the crankset. The IMEI code is separate and is used for built-in connectivity.
That number matters. It helps you register the bike, check if it has been reported stolen, prove ownership, value it and sell it with more buyer confidence. Here is where to find it, how to read it, and how to check it before you buy.
Check a Decathlon frame number
Free, instant, no signup. Enter the number stamped on the frame to check it against the UK stolen-bike databases.
A Decathlon connected bike serial number is a 10-character code made from letters and numbers. Depending on model, check the seat tube, seat post or frame to the left of the crankset. Do not use the IMEI code as the frame number.
Check the seat tube, seat post or crankset area.
Decathlon places the serial number differently by model, so check all three documented spots before assuming it is missing.
- Put the bike somewhere stable and well lit.
- Check the seat tube (Elops 920E and similar models).
- Check the seat post (LD920E and Speed900E).
- Check the frame to the left of the crankset (Cargo F900E).
- On non-connected Decathlon bikes, also check under the bottom bracket between the pedals.
- Take a clear photo before typing the number into a checker.
Make sure you copy the full number. A single missing or misread character can give the wrong result.
Can’t find it in the documented spots?
If the number is not on the seat tube, seat post or crankset area, check these places next:
- The original Decathlon receipt or account order history.
- The Decathlon registration record.
On older bikes, repainted frames and heavily used bikes, the number can be harder to read. If it has been scratched off, covered, filed down or looks tampered with, treat that as a serious warning sign.
What does a Decathlon frame number look like?
Decathlon describes the bike serial as a 10-character code using numbers and letters. The IMEI is different: it usually starts with 35 or 86 and has 15 digits. For stolen-bike checks and ownership, use the bike serial number, not the connectivity IMEI.
Do not use the model name, tyre size, barcode on a shop label, or any number printed on a component. The frame number belongs to the bike frame itself. For example, these are not usually the frame number:
- Rockrider
- B’Twin
- Elops
- Riverside
- Triban
- Van Rysel
- LD920E
- Speed900E
- Cargo F900E
- RC500
- RC520
- E-ST
- Geocover IMEI
- APIC code
- Battery serial number
- Motor number
- Charger number
- Product SKU
The number you want is the unique frame code that belongs to the frame itself.
Bike serial vs IMEI
Decathlon connected bikes can have both a bike serial number and an IMEI code. The bike serial identifies the bike. The IMEI identifies the connected module. For stolen-bike checks, use the bike serial number.
The detail that protects you.
A frame number is one of the most useful details on a used bike. It connects a Decathlon to its owner, its registration record and any stolen-bike reports.
You may need it to:
- Check if a Decathlon bike has been reported stolen.
- Register your bike.
- Sell your bike with confidence.
- Get an accurate bike valuation.
- Make an insurance claim.
- Report a stolen bike to the police.
- Prove the bike is yours.
If you own a Decathlon, take a photo of the frame number and keep it with your receipt. If the bike is ever stolen, that detail can make a real difference.
Buying a used Decathlon? Check the frame number first.
A clean-looking bike is not always a safe buy. Before you pay, ask the seller for a clear photo of the frame number and check it against stolen-bike records. You should also ask for:
- The original receipt or proof of purchase.
- The seller’s name matching the receipt where possible.
- Clear photos of the bike from both sides.
- A photo of the frame number.
- Any service history.
- Details of upgrades or replacement parts.
Red flag. Be careful if the seller refuses to show the frame number, says they cannot find it, gives only a partial code, or pressures you to pay quickly. A genuine seller should understand why you are checking.
Check a Decathlon frame number on Cyclesite
Found the number? Run a free stolen-bike check before you buy. Enter the Decathlon frame number into the checker and look for any matching reports. It only takes a moment, and it can help you avoid buying a bike with a bad history. If the bike looks clear, you can also value it and compare similar Decathlon bikes for sale.
What to do if your Decathlon has been stolen.
Report it as soon as possible. You will usually need the frame number, photos, make, model, colour, size, location and any unique marks or upgrades.
- Report the theft to the police.
- Get a crime reference number.
- Add the bike to stolen-bike databases.
- Update any existing bike registration record.
- Contact your insurer if you have cover.
- Watch used bike listings for matching bikes.
- Keep photos, receipts and messages in one place.
Include anything distinctive, such as upgraded wheels, unusual tyres, scratches, stickers, lights, mudguards, racks or replacement parts. The more detail you provide, the easier it is to identify the bike if it appears for sale.
Decathlon frame number FAQs
Where is the serial number on a Decathlon LD920E?
Decathlon says the serial number is a 10-character code found on the seat post.
Where is the serial number on a Decathlon Speed900E?
Decathlon says the 10-character bike serial number is on the seat post.
Where is the serial number on a Decathlon Cargo F900E?
Decathlon says it is on the frame to the left of the crankset.
Where is the serial number on an Elops 920E?
Decathlon lists the Elops 920E serial number as being on the seat tube.
Is the Decathlon IMEI the bike frame number?
No. The IMEI is for the built-in connectivity module. Use the bike serial number for stolen-bike checks.
Can I check if a Decathlon bike is stolen by serial number?
Yes. Use the bike serial number to run a stolen-bike check before buying, and ask for the original receipt or account order history.
Looking for another brand? See the full bike frame number guide.
Bottom line
Depending on the model, a Decathlon serial number sits on the seat tube, the seat post or the frame to the left of the crankset. Copy the full 10-character code, ignore the IMEI, then check it before you buy, sell or register the bike. A used Decathlon can be a brilliant buy, but the serial number is the detail that protects you.
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Last reviewed by the Cyclesite editorial team. Published by Cyclesite, Companies House No. 13238473.