How to read Mongoose serial numbers for mid-school and new-school BMX bikes

Your guide to old Mongoose serial numbers. Find our what year your BMX was built and sold and date mid school and new-school bikes made between the mid 90’s to mid 2000’s. The guide covers many serial numbers but not all. There were many different factories making Mongoose BMX bikes and all had different serial number codes.

Mongoose serial number information has never really been properly documented, possibly lost as the company changed hands and moved production. However, there are a few BMX restorers who have painstakingly attempted to decipher these multi-digit mysteries.

Mongoose BMX serial numbers 1

Mongoose BMX serial numbers 2

Mongoose BMX serial numbers 3

Mongoose BMX serial numbers 4

A big part of buying, rebuilding and restoring old BMX bikes, is knowing exactly how old they are. When I started looking into finding out how to read Mongoose serial numbers I found plenty of information on Mongoose BMX bikes made in the 80’s and early nineties through google and BMX forums. The problem was there was no information helping to date Mongoose BMX bikes built from 2000 onwards. It seemed nobody figured out how to read the serial numbers.

Older Mongoose bikes made through the 1980’s had pretty easy serial numbers. Generally the year and month of build was stamped as the first part of the serial number. For example my 1986 Mongoose Expert has a serial number M6EG0652. The first number (6) relates to the year – 1986. The next letter relates to the month (E) is May based on the convention January (A), February (B), March (C), April (D), May (E), June (F), July (G), August (H), September (I), October (J), November (K), December (L). It is assumed that the G0652 is the production number. There were a few variations on this type of serial number, but usually they were pretty easy to work out.

There are much more difficulties when looking at Mongoose serial numbers through the 1990’s and 2000’s. I spent quite a bit of time looking into these numbers on a few of my bikes as well as checking against other Mongoose BMX owners to see if my serial number crack was right. It seems to hold up and here it is.

Mongoose serial numbers are usually found stamped on the bottom of the bottom bracket. This is not always the case and there will be some bikes that do not fit into this formula.

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


A few serial number examples are:

HFGB00000 – 4 letters, GB are the dates. G is the year (1997), B is the month (Feb)

HFBH00000 – 4 letters, BH are the dates. B is the year (1992), H is the month (Aug)

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

A few serial number examples are:

HAMME00000 – 5 letters, ME are the dates. M is the year (2003), E is the month (May)

SAJPJ00706 – 5 letters, PJ are the dates. P is the year (2006), J is the month (Oct)

Please note: The Mongoose serial number will give you the build date of your BMX. Frames were normally manufactured the year before being sold in bike shops. So a build date on a frame of 2003 usually means the bike was sold in stores in 2004. This is the case with the 2003 Mongoose Brawler 24 below. The Serial has a build date of 2003, the 2004/004 on the stickers indicate this was a 2004 model.

Mongoose BMX serial numbers 5

Mongoose BMX serial numbers 6

I have confirmed this Mongoose serial number crack many times against bikes that have been known to be purchased that year, bikes with distinct graphics and colours and checked them against Mongoose BMX catalogues.

If you have a Mongoose BMX that doesn’t fit into the serial number style above, go to this thread on the OZBMX forum and post a couple photos of your bike and make sure you include the serial number in your post. I will look into all the numbers listed.

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  • jane slgram

    my serial no is HOIJ02270L 43 what year is it please

  • Wally Squier

    Couple question if you could take the time. My S/N is ACL6F11569 I can not find it anywhere on the net do you have any insight? Also the front fork is at almost 90 degree angle from the ground? someone said is was bent, someone else said they were made that way to allow easy 360 degree rotation of front end. Thank you Wally

  • Shawn Thomas

    Please help me!! #s are snacy11e25848, can’t find no info on it, please help, buddy!!!

  • Bryan

    Thanks for your work on the subject…well done!!!! I have just aquired a 1997 Mongoose Expert Comp in Chrome,,,,should clean up decent……..nice bike!!!!

  • Carl Heltzel

    Hi, my serial no. is STACY11C02377
    Any idea about the year it was built? Thanks

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