Do I need special stamps for international mail?

Do I need special stamps for international mail?
Customers can use Forever Stamps for international mail, but since all international prices are higher than domestic prices, customers will need to attach additional postage. The value of the Forever Stamp is the domestic First-Class Mail letter price in effect on the day of use.

Reference:
Forever Stamp Fact Sheet - USPS
Aug 5, 2019

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