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BMX Serial Number Chart: What You Should Know

Whether you’ve inherited an old BMX bike, found a decent looking BMX frame that you want more details on, or you’re just curious about how to decipher BMX serial numbers, we got you.

We did a deep dive into all things BMX serial numbers to help you find the details you need to know about your BMX bike frame.

Keep reading to learn what you need to know about reading BMX bike serial numbers.

How do I know what BMX frames I have?

If you’ve ended up with a second-hand BMX bike frame, then you may have no clue what you’ve really got there.

Fortunately, there is a relatively easy way that you can find out.

You don’t have to worry if there are no decals or stickers on the frame because all you need is the serial number.

The serial number on the BMX frame tells you what frame you actually have there in front of you.

Often, this is located on the bottom bracket of the frame.

But some BMX bikes put the serial on the rear dropout.

bmx bike serial number
image: vitalBMX

Another alternative is that you can take the frame into your local BMX bike shop and ask the clerk if he has any insight for you.

BMX bike employees and owners are usually pretty knowledgeable about this sort of stuff.

How do you read a BMX serial number?

First things first, in recent decades there have been changes to the numbering style the BMX bike brands use for serial numbers.

So, that can make it a challenge when trying to read the serial number on a BMX frame of unknown origin.

Here’s a quick primer on how things have changed and how you can read the serial number on your BMX frame.

Back in the 80s, bike manufacturers kept it simple and easy to decipher with the production year listed in the serial number, such as 86 to denote the year 1986

This simple numbering system was in place until 1987.

At that point, the first letter of the BMX bike brand was added before the year and two digits were added after the year to denote the month, such as H8806 for a June 1988 bike from the Haro BMX brand.

Fast forward to 1990 and the BMX serial numbering system changed again.

The big change in 1990 was replace the two-digit month of product with a letter that corresponds to the chart below.

  • January = A
  • February = B
  • March = C
  • April = D
  • May = E
  • June = F
  • July = G
  • August = H
  • September = I
  • October = J
  • November = K
  • December = L

The HARO BMX bike serial numbers underwent additional changes in 2000.

How do I find out what year my BMX bike is?

The bike’s serial number is the best way to determine what BMX model year you’ve got there.

Use our guide and chart above to determine what year your BMX bike is.

If you are still having issues determining when your BMX bike was sold, you can go into a local bike shop to ask if they know or look for old literature from the brand online in the Wayback Machine.

Can you look up a bike model by serial number?

Yes, the website bikeindex.org has a pretty big collection of bike serial numbers and an easy search function.

While they do not claim to have 100% of bike model serial numbers, this resource is a great place to start your search.

How do you date a Mongoose BMX?

For Mongoose BMX bikes built in the late 80s and early 90s, the serial number system is easy to decipher.

Both the model and month it was build in are listed in early part of the number.

Re-Ride gives the example of a 1986 Mongoose Expert having the serial number M6EG0652.

Here’s how to decipher that example serial number above:

  • first digit = factory code
  • second digit = year 
  • third digit = the model
  • fourth digit = production month (see chart above)
  • numbers after the month = the production line number

For the rest of the 90s and the 2000’s, the Mongoose BMX serial numbers changed.

However, Re-Ride has cracked that code and notes the following:

Mid-school Mongoose BMX bikes built through most of the 90’s have a serial number that begins with 4 letters. The 3rd letter corresponds to the year of manufacture.

A      B     C      D     E      F      G      H      I
91   92    93    94    95    96    97    98    99

The 4th letter indicates the Month

A      B       C      D       E        F       G       H       I          J       K        L
Jan  Feb  Mar   Apr   May   Jun   Jul    Aug    Sept   Oct   Nov   Dec

New-school Mongoose BMX bikes built through most of the 2000’s have a serial number that begins with 5 letters. The 4th letter corresponds to the year of manufacture and follows on from the mid-school serial numbers.

J      K     L     M    N    O     P     Q     R     S
00   01   02   03   04   05    06   07    08   09

A      B       C      D       E        F       G       H       I          J       K        L
Jan  Feb  Mar   Apr   May   Jun   Jul    Aug    Sept   Oct   Nov   Dec

Why do Haro frames have different a build date and model date?

If you’ve looked at some of the serial numbers for the Haro frames, then you’ve likely noticed the the model year and the year in the serial number don’t match.

That’s because the frames are manufactured the year prior to their release.

And the model date is based on the release date, not the manufactured date.

Benefits of knowing your BMX bike’s serial number

There are several good reasons to get that serial number off the frame of your BMX frame.

If the frame is new to you, then it allows you to check the model date and year.

If the bike is ever stolen, the serial number is vital in tracking down that lost bike.

If you live in a place where your bike needs to be registered, then you’ll need that serial number.

Final Word

As you can see, deciphering that serial number on your BMX frame doesn’t have to be difficult.

Depending on when the bike was made, the process of reading that serial number may be really easy.

Use our tips above to get to work deciphering your own BMX bikes’s serial number.

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