Yes. You may use two ordinary Forever stamps on a qualifying nonmachinable letter if their combined value covers the required postage. At 82 cents each, two stamps provide $1.64. A one-ounce domestic letter plus the current 49-cent nonmachinable surcharge totals $1.31, so two stamps cover it but overpay by 33 cents. USPS does not return change for excess postage.
Two stamps solve payment, not mailpiece classification
Adding stamps does not make a rigid object, thick mailer or parcel eligible for letter pricing. The finished piece must first satisfy USPS letter dimensions and weight limits. If it is too thick, too rigid or not uniformly thick, another mail class or parcel price may apply.
Common nonmachinable characteristics
- Square or nonrectangular shape
- Aspect ratio outside the machinable range
- Rigid contents or insufficient flexibility
- Clasps, strings, buttons or similar closures
- Uneven thickness
Should you use a butterfly stamp instead?
A current Nonmachinable Surcharge stamp is designed to represent the applicable one-ounce letter price plus the surcharge. Two ordinary Forever stamps are a valid combination when they cover the total, but the purpose-made stamp can reduce overpayment and make the intended postage category clearer. Verify its current value before use.
Before mailing
- Weigh and measure the finished envelope.
- Check whether it remains letter-size.
- Identify the nonmachinable characteristic.
- Compare the required postage with the value of the stamps applied.
- Ask USPS to inspect an unusual piece when classification is uncertain.
Read the butterfly postage guide or browse nonmachinable stamps. Current price and mailpiece rules were checked against USPS Notice 123 and the Domestic Mail Manual on September 3, 2026.
For other envelope, weight, destination, and service scenarios, use the Forever stamp calculator and postage guide.