This prefix letter was added to the serial numbers on $5 and higher notes starting with Series 1996. It changes whenever the series year or series year suffix letter changes. * The prefix letter on the serial number for denominations $5 and higher indicates the note series. Serial Numbers - Series Year and Serial Number Relationship Table Denomination The last letter still can be anything but O or Z, and is still occasionally replaced by a star, with the same meaning as before. On these notes, the first letter corresponds to the series of the note and the second letter of each serial number now represents the issuing FRB and ranges from A through L. A 'star' note has its own special serial number followed by a star in place of a suffix letter.įederal Reserve notes, beginning with Series 1996, have two letters rather than one at the beginning of the serial number.

Reusing an exact serial number to replace an imperfect note is costly and time consuming. A 'star' sheet is used to replace the imperfect sheet. When an imperfect sheet is detected during the manufacturing process after the serial number has been overprinted, it must be replaced with a new sheet. On some notes, a star appears in place of the last letter. The letter O is not used because of its similarity to the digit 0, and the letter Z is not used because it is reserved for test printings. At the time of a series change, the suffix letter returns to the letter A and repeats the cycle. The last letter advances through the alphabet when all eight character serial numbers have been printed for a specific Federal Reserve Bank within the same series. The first letter of such a serial number identifies the Federal Reserve Bank (FRB) which issued the note since there are 12 FRBs, this letter is always between A and L.

Lookup star note