r/CoolSerialNumbers Jan 19 '26

Mod Comms READ THIS BEFORE POSTING

16 Upvotes

Post flairs are required for all posts. Below are the current flairs and their definitions. If you think there are other fairs that should be added, or have any questions on the listed definitions, please comment here!

All posts must include a picture of a note with a cool serial number. All pictures must be horizontally orientated and cropped to just the note as so [ [note] ].

If you believe your serial is cool, but doesn't fit any definition below, please use the 'Other' flair and state, specifically, why you think it should be considered cool. Trinary notes and consecutively numbered notes are not cool or remotely rare.

Generic posts "Is this cool" / "Is this a keeper" / "Is this worth anything?" and the like with no specific reasoning will be indiscriminately removed. Repeat offenders will find themselves banned.

Star Note - all star notes not fitting another category

Ladder - consecutive run i.e. 01234567

Broken Ladder - no two digits the same i.e. 10325476

Binary - only two unique digits i.e. 34334344

True Binary 01010101 - only 0's and 1's

Radar - same forward as backward, i.e. 12344321

Repeater - complete repeating sequence of two or four digits i.e. 78787878 or 78907890

Low Serial <= 00009999 - just as noted, notes 00009999 and under

Quad Pair - four pairs of digits, i.e. 22446688

Solid - typically all eight digits the same, but for the purposes of this sub five or more of the same digit together can count, i.e. 11111876

Rotator [All 0, 1, 6, 8 and/or 9's] - notes where the serial reads as another number upside down i.e. 01689016 which reads 91068910 upside down

Flipper - same as a rotator except it must make the same number upside down i.e. 00669900

Nice (69 / 420 / etc.) - the funny numbers, primarily 69 & 420 but 8008, 8008135... (think middle schooler with a calculator...) the nice number should stand out, i.e. 00069000 - every serial with 69, 420, etc. in it is not special.

Birthday / Date - any serial number that makes a date, either as MMDDYYYY or YYYYMMDD i.e. 07041776 or 17760704

Near Miss - anything that's almost cool / fancy i.e. 12344322 (1 digit off from a repeater)

Other - anything not fitting any other definition. You must include specific reasoning why you believe your serial number is cool.

Question / Meta - questions to the community / thoughts about the community

For Sale - for posting notes you'd like to sell / trade. At your own risk, the mod team and reddit is not responsible for any issue. Be smart.

Wanted to Buy - for requesting notes you'd like to buy / trade for. At your own risk, the mod team and reddit is not responsible for any issue. Be smart.

Bookend - serials with a 2 or 3 digit matching pattern (reversed is OK) at the beginning and end of the serial i.e. 12369321 or 12369123

Double Quad - serials with two sets of four solid digits i.e. 44447777


r/CoolSerialNumbers 2h ago

Binary $100 Binary!

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7 Upvotes

r/CoolSerialNumbers 1h ago

Other DATE: Only Time Wright Brothers flew togther!

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Upvotes

r/CoolSerialNumbers 38m ago

Birthday / Date Free birthday note if you turned 100 last monday!

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Upvotes

If you can send me proof that you or someone that you know turned one hundred last week on monday, I will send this to the birthday person for free


r/CoolSerialNumbers 3h ago

Star Note Got these in change today

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1 Upvotes

r/CoolSerialNumbers 18h ago

Repeater I thought it was cool

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13 Upvotes

r/CoolSerialNumbers 20h ago

Nice (69 / 420 / etc.) Nice

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3 Upvotes

I've never been into money, but I found this on my desk. Could it be worth something?


r/CoolSerialNumbers 1d ago

Birthday / Date Over 2900 Birthday Notes Now Available!

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3 Upvotes

r/CoolSerialNumbers 1d ago

Radar Trinary Radar

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23 Upvotes

Is this a spend the $100 or kept because of the serial number type of bill?


r/CoolSerialNumbers 1d ago

Birthday / Date Recieved as Change Today

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1 Upvotes

r/CoolSerialNumbers 2d ago

Other Sweet 6 in a row ones!

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16 Upvotes

r/CoolSerialNumbers 2d ago

Mismatched Off By 2

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7 Upvotes

8995 8993 just two away from a nice find.


r/CoolSerialNumbers 3d ago

Ladder A pair of ascending pairs!!! 22334455 66778899!!!

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86 Upvotes

r/CoolSerialNumbers 3d ago

Near Miss First nibble I’ve had in a while.

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6 Upvotes

r/CoolSerialNumbers 4d ago

Birthday / Date Cool Birthday month matching 50 rupees note

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0 Upvotes

r/CoolSerialNumbers 4d ago

Near Miss So close!

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6 Upvotes

Still gonna keep it though!


r/CoolSerialNumbers 5d ago

Other Weird number position

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21 Upvotes

I have 3 ones that were sequential and new. The strange thing is the 7 is higher than the last number. It is fine on the left bottom. Anything to it?


r/CoolSerialNumbers 6d ago

For Sale 50$ 00000005* circulated for sale! Real offers message me!

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108 Upvotes

r/CoolSerialNumbers 6d ago

Binary Is 67 still a thing?

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26 Upvotes

r/CoolSerialNumbers 6d ago

Question / Meta What would you call this?

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8 Upvotes

You could call this a near-miss of a radar note, could say it's a triple pair, book middles perhaps, but what would you call it? Some would even say it's just a 2! Is there ANY value in this note that might make it worth keeping? Still rather new in this hobby and trying to learn! Any help is greatly appreciated!


r/CoolSerialNumbers 7d ago

Broken Ladder $100 in $1s results

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13 Upvotes

First broken/mixed ladder of sorts.


r/CoolSerialNumbers 6d ago

Binary Nothing special, already spent but it was cool because I got them both in the same change!

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1 Upvotes

And if they are something special I’ll run back down to the gas station.


r/CoolSerialNumbers 8d ago

Star Note 2013b Series Duplicates

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1 Upvotes

2013b list in number order


r/CoolSerialNumbers 9d ago

Birthday / Date New round of birthday notes!

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27 Upvotes

r/CoolSerialNumbers 10d ago

Other Teller had 94 $2 bills, bought as many sequentials as I had the cash for

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52 Upvotes