what does an additional ounce stamp cost

An additional ounce stamp costs 29 cents in the U.S. right now. USPS lists the Additional Ounce stamp at $0.29.

Useful detail

• For a standard letter, the first ounce is covered by a regular First-Class stamp.
• If your letter goes over 1 ounce, you add one additional-ounce stamp for each extra ounce.

Example

A 2-ounce letter typically needs:

• 1 regular stamp for the first ounce.
• 1 additional-ounce stamp for the second ounce.

The USPS store and current postage-rate listings both show the additional- ounce rate as 29 cents.