Direct answer: Genuine unused U.S. postage stamps generally do not expire merely because they are old. They must still be valid under USPS rules, intact and unused. A fixed-denomination stamp contributes the value printed on it; an older lettered stamp contributes its USPS-assigned issue value; an ordinary Forever stamp follows the current one-ounce First-Class Mail letter-rate value.
Direct Answers by Stamp Type
| Stamp type | Does age make it expire? | Value when used |
|---|---|---|
| Ordinary Forever | No | Current ordinary one-ounce letter-rate value |
| Fixed denomination, such as 10¢ or 39¢ | No, if otherwise valid | The amount printed on the stamp |
| Older A–H lettered stamp | No, if otherwise valid | The official value assigned to that issue |
| Nondenominated Postcard, Additional Ounce or other labeled type | No, if otherwise valid | The current applicable labeled rate category |
Can Old Non-Forever Stamps Still Be Used?
Yes, generally. Add their printed or officially assigned values until the total meets the postage required for the finished mailpiece. They do not automatically become worth the current Forever rate.
When an Unused Stamp Is Not Valid
- It is counterfeit or an imitation.
- It was already canceled or used.
- It is mutilated, defaced, substantially incomplete or covered so it cannot be canceled.
- It is foreign postage, a nonpostage label, or another category USPS lists as invalid for U.S. postage.
- The stamp itself is valid but the total affixed does not meet the required postage.
What Should You Do With an Unclear Old Stamp?
Do not guess from the picture alone. Record the wording, printed denomination, year and design, then identify the issue through USPS information or ask a Post Office to confirm how it may be used. Compare fixed-value and Forever postage in the denomination guide.
Sources checked August 25, 2026: USPS DMM 604; USPS stamp types; USPS guidance on torn stamps.