Reviewed September 12, 2026. USPS stamps can be classified by postal value, mail use, format and subject. These are different dimensions: artwork does not determine value, and a booklet or coil is a package format rather than a postage category.
Core value categories
| Type | Value basis | Typical use |
|---|---|---|
| Ordinary Forever | Current one-ounce domestic letter rate | Qualifying First-Class Mail letter |
| Fixed denomination | Printed cents or dollars | Part or all of any eligible postage total |
| Postcard | Current domestic postcard category | Qualifying postcard |
| Global Forever | Current qualifying one-ounce international letter/postcard category | Eligible international mail |
| Additional Ounce | Current named additional-ounce value | Adds weight-related letter postage |
| Nonmachinable | Current named category value | Supports qualifying nonmachinable letter postage |
| Semipostal | Postage component plus fundraising amount at sale | Program-specific stamp |
Official value rules: USPS DMM 604.
Commemorative and mail-use labels
A commemorative stamp marks a person, event or subject. A mail-use stamp is designed for ongoing postal needs. Either may be denominated or nondenominated. Do not infer Forever status from artwork or collectibility.
How to choose
- Classify the finished mailpiece.
- Calculate the current total.
- Read each stamp’s denomination or named category.
- Combine valid values to meet the total.
- Show any overpayment.
“Make-up stamp” is an informal description for postage used to fill a shortfall, not proof of rarity. Collectible advice requires separate evidence.