Additional Ounce Stamps
2017-Uncle Sams Hat Stamp Additional Ounce Postage Stamps
Additional Ounce stamps are designed to add the current extra-ounce postage for eligible First-Class Mail letters. At the rates effective July 12, 2026, that value is 29 cents. They are useful when a standard letter weighs more than one ounce but still qualifies for letter pricing.
How to use an Additional Ounce stamp
For a qualifying two-ounce domestic letter, combine one ordinary Forever stamp with one Additional Ounce stamp. At current rates, that totals 82 cents plus 29 cents, or $1.11. A three-ounce qualifying letter generally adds a second Additional Ounce stamp. Always calculate from the finished piece.
What it does not solve
An Additional Ounce stamp does not correct a large-envelope classification, nonmachinable surcharge, package price, or international rate by itself. Size, thickness, rigidity, and destination still matter. Use the full stamp calculation guide when the envelope is not a standard rectangular letter.
Rate checked August 25, 2026. Verify current prices at USPS before mailing.
Page reviewed: August 25, 2026. Product availability and postal rates can change.