Answer (1 of 21): My understanding is that the U.S. “Forever” stamps are not valid for international mail because they do have a value printed on them. Like Canada’s similar “Permanent” stamps, they are intended for domestic use only. That doesn’t mean that your mailing will, for certain, not get
When posting a letter to a foriegn country will the letter still
Can the second ounce stamps be used as regular stamps to send
How Many Stamps Do I Need? and Where You Can Buy? - PostGrid
What is a Forever Stamp worth? It covers the first ounce, but do I
Are postage stamps worth any money? - Quora
What is the value of old post stamps? - Quora
How many stamps do I need to send an international package? - Quora
Are all U.S. postage stamps “Forever” stamps now? - Quora
Why are postal stamps important? - Quora