US lawFederal (United States)Session lawPub. L. 86-682 — To revise, codify, and enact into law, title 39 of the United States Code, entitled “The Postal Service”.Title 39Part IV4051Pub. L. 86-682, tit. 39, pt. IV, ch. 53, sec. 4051Prepayment of postageEnactedYear: 1960Length: 20 wordsOfficial source § 4051. Prepayment of postage Except as otherwise provided by law, postage shall be prepaid at the time of mailing.PreviousPub. L. 86-682, tit. 39, pt. IV, ch. 51, sec. 4007NextPub. L. 86-682, tit. 39, pt. IV, ch. 53, sec. 4052