At the rates effective July 12, 2026, three Additional Ounce stamps equal or exceed one ordinary Forever stamp. Each Additional Ounce stamp is worth 29¢, so three total 87¢. An ordinary Forever stamp is worth 82¢, so this combination overpays by 5¢.
Current Value Formula
3 × 29¢ = 87¢
87¢ − 82¢ = 5¢ overpayment
Two Additional Ounce stamps total only 58¢ and are therefore 24¢ short of the ordinary one-ounce letter rate.
Value Equivalence Is Not the Normal Mailing Method
An Additional Ounce stamp is designed to pay the price for one extra ounce on an eligible First-Class Mail letter after the base one-ounce postage has been paid. The clearest standard combination is:
- Up to 1 ounce: one ordinary Forever stamp
- More than 1 ounce up to 2 ounces: one ordinary Forever plus one Additional Ounce stamp
- More than 2 ounces up to 3 ounces: one ordinary Forever plus two Additional Ounce stamps
Using three Additional Ounce stamps by themselves can supply enough total value for a one-ounce letter, but it is less intuitive and currently costs 5¢ more than necessary.
Why Additional Ounce Stamps Do Not Equal Ordinary Forever Stamps
Both are nondenominated stamps whose value changes with a USPS price category, but they follow different categories. Ordinary Forever tracks the single-piece one-ounce First-Class Mail letter price. Additional Ounce tracks only the current additional-ounce price.
The word “Forever” in casual descriptions does not make the two categories equal. Read the wording printed on the stamp.
Can You Combine the Two Types?
Yes. Valid unused postage can be combined to reach the required total. For a two-ounce standard letter, one ordinary Forever stamp plus one Additional Ounce stamp is the intended combination. You may also combine other valid denominations, but USPS does not refund routine overpayment on a mailed piece.
Current Letter Examples
| Eligible letter weight | Current required value | Simple stamp combination |
|---|---|---|
| Up to 1 ounce | 82¢ | 1 ordinary Forever |
| More than 1 up to 2 ounces | $1.11 | 1 ordinary Forever + 1 Additional Ounce |
| More than 2 up to 3 ounces | $1.40 | 1 ordinary Forever + 2 Additional Ounce |
These examples assume a machinable, rectangular First-Class Mail letter. Square, rigid, unusually thick, large-envelope, package or international mail uses other rules.
Frequently Asked Questions
Will two Additional Ounce stamps mail a one-ounce letter?
No. At current rates, two total 58¢, which is below the 82¢ base letter price.
Can I put three Additional Ounce stamps on a normal letter?
They total enough value, but you would currently overpay by 5¢. One ordinary Forever stamp is simpler.
Does an Additional Ounce stamp expire?
A genuine, unused nondenominated Additional Ounce stamp remains valid for the current Additional Ounce category, not the ordinary Forever category.
Will the answer change?
It can. Recalculate whenever either the ordinary one-ounce letter price or the Additional Ounce price changes.
Official Sources
See the USPS postage-payment rules and the July 2026 price implementation.
Rates checked September 1, 2026.