Almost all bicycles have a unique identification number engraved into their frame. This number is usually between seven and ten digits long, and it's called the “bike serial number” or “bike frame number”.
Where can I find my bike serial number?
You can usually find the bike serial number on the under side of the bottom bracket. The “bottom bracket” is the part of the frame that the pedals go into.
So all you have to do is turn your bike upside down and have a look…

The bike serial number is usually on the underside of the bottom bracket
If it’s not there, don’t worry! On some bikes it will be elsewhere on the frame. So if you don’t see it on the bottom bracket, check:
- Head tube
- Rear dropout
- Bottom of seat tube
- Top of crank
If you're confused by these names, check out my complete guide to the parts of a bike or, I've also labelled them on the image below!

Other places the number could be
Some Schwinn bikes and Rad Power bikes have the serial number engraved into the head tube. Other Schwinn bikes and some BMX bikes have the number on the rear drop out.

Serial numbers on the head tube and rear dropout
The only bikes that won’t have a serial number engraved somewhere on their frame are either very old or hand made (some bespoke frame makers don’t assign frames numbers).
So if you don’t see it a first, keep looking. I was beginning to think that my old bike didn’t have one before I finally found it at the top of the seat tube!

I finally found mine at the top of the seat tube!
What does my bike serial number mean?
A bicycle serial number is a unique number allocated to your bike by the manufacturer. It helps the manufacturer and bike shops with inventory, making it easier to match compatible parts to that bike.
Each manufacturer has their own identification system. But the first numbers usually indicate the year, and then month of manufacture. And the remaining numbers indicate the specific ID of that bike.
The best way to read a bicycle serial number is to search the web for “[brand name] bike serial number decoder”.
Why is the bike serial number important?
You will hear many people (including me) banging on about the importance of knowing your bike serial number.
That’s because when your bike is stolen, it’s the serial number that gives you the biggest chance of getting it back.
You use the serial number to register your bike with the various registration schemes such as Bike Index, Bike Register and Project 529. If the police recover your bike, they'll use the serial number to link it to you.
And it’s the serial number that will prove to anyone that the bike is definitively yours.
Unfortunately it doesn’t seem to matter how much we bang on about how important this is! Because over 80% of cyclists don't know their frame number. Which means that the chances of them getting their bike when it’s stolen are tiny.
So, don’t be one of those people! Go and find your serial number now. Photograph it. Email it to your self. Register your bike with one of the bike registration organisations.
Be a winner!
What does the PAN under my right pedal, opposite the serial number mean?
How do you go about getting parts for a bike you like and it’s a mongoose is 27 mm I do have the serial number snfsd10h84861 I will really appreciate it thanks
What is a scbwinn girl bike worth with the jj579287
I have acquired a bicycle BMX bike it’s a Pro Cycle design and it’s called Commando and the serial number GBPF922668 now I’ve searched cant seem to find any match anywhere or someone who has knowledge about this are you able to help with who made it or what year and perhaps what I can possibly get for it being a antique and all its all together and original with suntour com
Brakes which is pedal backwards to brake
Serial number CB5J044S0 or CBSJ04450 what type of bike is mine?
What a kind of bike with serial number 038818005
What bike do I have? 1981200052
I looked all over the tricycle and I can’t find any numbers! The Guy I bought it from told me that it is a 1955 Swinn. I would like to know the right year that it was made.
I have a parsley 3 wheel tricycle and I’m looking for my serial number / frame number now to be on the safe side.
I have a 1969 schwinn 5 speed serial number EE54627 what type of bike do I have
1969 schwinn 5 speed
GS100700032
I have an mirraco BMX bike how can I find serial no.GMT40307311
Too find out what kind of bike you have buy checking the Numbers
I’m trying to identify this old magna 10 speed what is it worth
Loco222644
I have a bike that says mongoose SNMNGO7A84096
I have a 20 inch Electra Rat Rod, with the serial no# being, ELWOO13419, can you tell me how old it is?
I have a scwhin but I don’t know the year GK50371327 is the serial number
I have the beach cruiser with the serial number g160 510-357 what kind of beach cruiser is it what year?
Trying to figure out what kind of bike I have
I have a kent 10 speed bicycle wondering what kind and year has A7352426 on it
Schwenkercharlie@gmail.com
I’ve got a bike, you can ride it if you like, it’s got a basket, a bell that rings and things that make it look good. I’d give it to you if I could but I borrowed it. Yer the kinda grrl that fits in with my world, I’d give anything, everything that you want babe.
-Pink
Was thinking about selling my old HUFFY WOMANS bike but it’s got some rest but that can be fixed easy everything on it is original The numbers on tires is E_703_23′ so will you get back to me plz and let me know how much do you think I could get for it thank you
How to find out what bmx bike I have
i have a old war bike the serial number is T325597
I have a bicycle that has a Columbia badge from Westfield Ma. It has an old script Bendix brake. A double top tube frame. The top bar goes to the rear fork. The rear fork is one bar and the fenders have a slight crease in the middle. It has three letters stamped in the frame and what looks to be a shield. Any ideas?
Snmng12eo4708
I have an older BMX bike that I cannot find anything to identify what it is?
I really started to enjoy bike ridding when I got my 820 . I have never had a bike that rides like this ,I will always be a trek fan
Got this bike tonight and am curious what it is serial number is JTY191204475 it’s a 20 in bmx
Bmc urs (unrestricted)
Road bike …
Serial#0r1911423
How much is this bike worth ??
What year is it …??
What model. Is it ???
Thank you
I have a ladies Schwinn made in Taiwan by giant. Serial number under bottom bracket is GY710086. Headbadge number is 3247. I’m wanting to know the year it was built.
Western flyer MOR 2535
457166
What does it mean when there are 2 serel numberrs
I have a Raleigh women’s bicycle
Ser.# 01-63-G
followed by another ser#
U54K27963.
Trying to find out date of manufacture and where… assuming it was China