Cost To Mail A Large Envelope 2024. Use usps priority mail express flat rate envelopes and pay one price: One of the more noteworthy changes for meter customers is that the usps ® will only be increasing metered postage by 1 cent, while increasing the cost of a.
Prices will rise by an average of 4%, with some. The baseline postage rate to mail a flat/large envelope has increased from $1.39 to $1.50 in postage.