June 27, 2023 The USPS new postage rates will go into effect July 9, 2023. First-Class Mail Product Current Price Jul 2023 1oz. Letter $0.63 $0.66 Postcards $0.48 $0.51 1 oz. Flats $1.26 $1.35 Additional Ounce $0.24 $0.24 Certified Mail Extra Services Current Price Jul 2023 Certified Mail $4.15 $4.35 Return. Receipt Retail $3.35 $3.55 For additional Rates and Information visit www.usps.com