How to Use the Forever Stamp for Overseas Mail
- 1). Enter the destination country and size of mail into the United States Postal Service's online International Price Calculator (see References 2). Enter the weight of the mail in pounds and ounces into the pop-up fields, and then press continue (see References 2).
- 2). Select the size that most closely matches the mail from the provided options, and then press continue. Review the options provided and select a postal service.
- 3). Subtract the current rate for a single first-class stamp from the total Post Office Price corresponding to the selected service. Affix the Forever Stamp to the front of the mail, along with postage totaling the difference between a first-class stamp and the total postage due.
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