How to Send a Letter or Postcard | USPS
www.usps.com › ship › lettersStep 1: Choose Envelope or Postcard Envelopes are for sending flat, flexible things, like letters, cards, checks, forms, and other paper goods. For just 1 $0.68 First-Class Mail ® Forever ® stamp, you can send 1 oz (about 4 sheets of regular, 8-1/2" x 11" paper in a rectangular envelope) to anywhere in the U.S.! Show More