When the Bureau of Engraving and Printing (BEP) discovers damaged or defective paper money, it gets replaced with appropriately named "Replacement Notes." Modern Replacement Notes have serial numbers that end in a star, so they are commonly referred to as "Star Notes."

Misconception 1: Serial numbers match those they replace

It is very common for people to think that Star Notes have serial numbers that match the note they replace. This is incorrect.

Here are some fundamentals of how the BEP prints paper money:

  1. Star Notes are printed in advance to use as necessary
  2. Serial numbers of Star Notes have absolutely nothing to do with the damaged notes they replace

The BEP prints LOTS of paper money every day. Nearly 450 million notes were printed in February 2022. Imagine how time-consuming it would be to remove a damaged sheet or pack and reprogram the printing presses to spit out specific serial numbers. Then work those numbers back into the correct piles. It is not feasible.

Think about that and it becomes obvious that star notes need to be printed ahead of time to be used as necessary on-the-fly. As such, serial numbers will not match the notes being replaced.

Misconception 2: Serial Number Unique-ness

This scenario has occurred several times: A person has a note serial number B00191073A (for example). They decide to put B00191073* in the Star Note Lookup and are surprised if it returns a result.

It is absolutely valid for B00191073* and B00191073A and B00191073B, etc to be printed and exist in circulation. To understand why you must understand some basics about serial numbers:

  1. Modern serial numbers include three parts: Prefix (on modern $5 and up), FRB letter, 8 digit number, Block letter (or star)
  2. Serial numbers (the entire letter/number/letter combo) are unique per series and denomination

The Block letter (at the end of serial number) is incremented after all eight digit numbers are used. For example, after B00000001A - B96000000A are printed, the next printing for the "B" FRB district would be in the range of B00000001B - B96000000B.

(There is more nuance here. Some older notes were printed up to 99999999, more recent serial numbers stop at 96000000 or 99200000. Block letters "O" and "Z" are not used.)

As you can see, B00191073* and B00191073A and B00191073B can all exist in circulation and be consider valid, unique serial numbers.