Feb 24, 2020 | Jackie Neely New Rates Effective January 26, 2020 In Effect (2019) New Rate (2020) First Class Mail Single Piece Letters (Metered) Weight Not Over (oz.) 1 50 cents 50 cents (no change) 2 65 cents 65 cents (no change) 3 80 cents 80 cents (no change) 3.5 95 cents 95 cents (no change) Large Envelopes (Flats) Weight Not Over (oz.) 1 $1.00 $1.00 (no change) 2 $1.15 $1.20 3 $1.30 $1.40 4 $1.45 $1.60 5 $1.60 $1.80 Priority Mail Express Flat Rate-Domestic Flat Rate Envelope $22.50 $26.35 Legal Flat Rate Envelope $25.70 $26.50 Padded Flat Rate Envelope $26.20 $26.95 Priority Mail Flat Rate Envelope $7.35 $7.75 Legal Flat Rate Envelope $7.65 $8.05 Padded Flat Rate Envelope $8.00 $8.40 Small Flat Rate Box $7.90 $8.30 Medium Flat Rate Boxes $14.35 $15.05 Large Flat Rate Boxes $19.95 $21.10