Where Is the Serial Number on a Bill?

United States currency includes various security features, with the serial number being fundamental. Each bill is assigned a distinct serial number, a unique combination of letters and numbers. This helps track bills and distinguish genuine currency from counterfeits, contributing to the integrity of the nation’s financial system.

Where to Find the Serial Number

The serial number on a U.S. dollar bill appears in two distinct locations on the front: the lower-left and upper-right quadrants. These placements ensure the number is easily visible for verification. The serial number is printed in green ink, which matches the Treasury Seal and other green elements on the bill. Its clear, bold font stands out against the intricate background design. This dual placement and consistent appearance are part of security measures to make counterfeiting more difficult and enable quick identification of a bill’s authenticity.

Anatomy of a Serial Number

Serial Number Structure

Understanding the components of a serial number provides insights into a bill’s journey through the printing process. For most U.S. dollar bills, specifically the $1 and $2 denominations, the serial number consists of a single letter, followed by eight digits, and concluding with another letter. This eleven-character sequence is unique to each note.

Component Meanings

The first letter of the serial number corresponds to the Federal Reserve Bank that issued the note, ranging from ‘A’ to ‘L’ for the twelve different Federal Reserve districts. The eight digits that follow serve as the sequential numbering for that particular block of bills. The final letter, known as the suffix or block letter, advances through the alphabet as new blocks of currency are printed. The letters ‘O’ and ‘Z’ are omitted from these sequences to prevent confusion with the numeral ‘0’ and because ‘Z’ is reserved for internal test printings. In some instances, a star symbol replaces the final letter, indicating a “star note” which is a replacement for a bill found to be imperfect during the manufacturing process.

Other Unique Identifiers on Currency

Beyond the serial number, several other identifiers on U.S. currency provide information about the bill’s origin.

Series Year

The series year, located in the lower-right quadrant, indicates when a design was approved or a new signature was incorporated. A letter following the year, such as “2004A,” signifies a minor design revision within that series.

Federal Reserve Seal and Signatures

The Federal Reserve Seal, positioned to the left of the portrait, is a black circular seal with a letter inside that identifies the Federal Reserve Bank that issued the note. This letter corresponds with the first letter of the serial number on $1 and $2 notes, linking the bill to its issuing bank. The signatures of the U.S. Treasurer and the Secretary of the Treasury are printed on the bill, the Treasurer’s below the Federal Reserve Seal and the Secretary’s below the Treasury Seal.

Treasury Seal

The Treasury Seal, a green emblem to the right of the portrait, represents the U.S. Department of the Treasury.

Plate Numbers

Smaller identifiers include the plate position number, a letter-and-number combination in the upper-left corner, which indicates the bill’s position on the printing plate. Face and back plate numbers, found on the front and back of the bill, identify the specific printing plates used. A small “FW” next to the face plate number signifies the bill was printed at the Bureau of Engraving and Printing’s Fort Worth, Texas facility.