First Class Postage Rates 2024 Large Envelope. Learn about the 2024 postage price change for usps services and products, and how it affects domestic and international mail. Usps first class large envelopes and flats can have a height ranging from 6 ⅛” and 12”, a.

The usps raised prices by 7.8% overall. The changes will raise mailing services product prices approximately 7.8 percent.