A postage stamp is a small adhesive paper issued by the United States Postal Service (USPS) that serves as proof of prepayment for postal charges. The stamp’s specified value indicates the amount of postage paid for the item’s delivery. A common belief is that stamps expire or become invalid following a rate increase. The reality is that postage stamps issued by the United States since 1860 are generally still valid for use and do not expire.
The Lifespan of US Postage
The United States Postal Service maintains a policy that postage stamps are usable indefinitely. A stamp purchased decades ago remains valid for its face value, meaning stamps do not have an expiration date.
The introduction of the “Forever Stamp” in 2007 simplified maintaining valid postage through rate changes. A Forever Stamp is a non-denominated stamp always equal to the current price of a First-Class Mail one-ounce letter, regardless of when it was purchased. When the First-Class rate increases, the value of a previously purchased Forever Stamp automatically rises to meet the new rate. This allows customers to stock up on stamps without needing to add supplemental postage later.
This perpetual validity applies to standard mail usage. Forever Stamps are sold at the current First-Class rate and simplify mailing for individuals who send standard letters within the United States. While the value of a Forever Stamp adjusts with rate increases, other types of stamps, such as those for postcards or additional ounces, are also non-denominated and adjust their value similarly.
Combining Denominated Stamps
Older stamps that display a specific monetary value, such as a 32-cent stamp, can still be used but are only worth the face value printed on them. If the current First-Class Mail rate is higher than the value of the denominated stamp, additional postage must be affixed to the mailpiece. The total value of all stamps used must equal or exceed the required postage for the item being sent.
This process often requires combining several stamps of different denominations to reach the necessary total. For instance, if a letter requires 68 cents in postage and a person only has 32-cent stamps, they would need to supplement the difference with smaller denomination stamps, such as 1-cent or 3-cent stamps. The USPS offers these low-value stamps specifically to help customers make up the difference when using older postage.
Customers can find the precise postage required for their mailpiece by using the USPS website’s postage calculator, which accounts for weight, size, and mail class. Although it is permissible to overpay slightly, the total postage must be visible on the envelope. This allows older, denominated stamps to retain their utility even as postal rates increase over time.
When Physical Condition Matters
While stamps do not expire based on age or value, their physical condition is a factor in their validity for postage. Stamps that are mutilated or defaced are not considered valid for domestic or international mail originating in the U.S. This rule exists because the automated cancellation machines used by the USPS rely on detecting substances in the stamp coating to verify postage.
A minor tear at the corner of a stamp generally does not invalidate it, as the standard is applied with common sense to account for normal handling. However, if a large portion of the stamp is missing, or if the denomination is no longer evident, the stamp should not be used for postage. Additionally, a stamp that has been previously used and canceled by the post office, indicated by an ink mark, cannot be reused.
Attaching a stamp with tape also renders it invalid because the tape prevents the cancellation mark from being applied, which signals to the postal service that the stamp has been used. Storing unused stamps in a cool, dry place away from humidity is advisable to prevent the adhesive from being compromised or the paper from becoming damaged. Specialty stamps, such as presorted or non-profit stamps, also have usage restrictions and can only be used for the specific mail they designate.