Question: how many stamps should i use to mail a 12 x 9 manila envelope?
Answer: If you are to use Forever stamps for manila envelopes, then you will require two Forever stamps for envelopes weighing less than one ounce. For international mail: A postage stamp known as the Global Forever stamp is used to mail postcards. The same is used for 1-ounce letters to be mailed anywhere in the world.