Presorted flats will increase to 0774. Find out more about our postal rates including our international rates and our package rates. Pin On Postage Stamps On Envelopes Letters up to 3 ounces will run you 078 in postage. Business letter postage rate . Become a Post Billpay biller - Accept customer payments online by phone and at Post Offices. 275 One CDDVD in a padded env is 366 to 406 4oz. Order postage online Customs regulations. Our effectSM Serving nonprofits and their agencies since 1997. From 2955 at Post Office. Large Flat Rate Boxes. 2021 Postage Rate Chart Changes. Length is the longest side of the parcel. For packages up to 13 oz prices start at 430. Presorted letters will remain the same at 045 each. 2021 Postage Price Changes - USPS. First-class postcards increased from 35 to 36. You send your customers letters and large letters that we sort on your behalf. We offer four distinct postal services. First-Class Mail Forever stamps cost 05...