Question: can i use 2 forever stamps on a square envelope?
Answer: You can use more than one Forever Stamp if you need to send a package or a letter that weighs more than an ounce. ... So if you paid $0.49 and the rate rises to $0.50, you can put two Forever Stamps on a package to get $1.00 worth of postage. You can also use Forever Stamps to send letters internationally.