Is it possible to use two postcard stamps when you are sending a letter?

Question

I have postcard stamps I feel i am never going to use, so I was wondering if you can use two of them since they are 26 cents??

Answer 1

use as many as you want to

Answer 2

yea u can

Answer 3

Yes you can, love:) They don't give an f, as long as you pay enough postage.