Automated Certificate of Mailing User Guide
From the USPS: A Certificate of Mailing (COM) may be presented only at the time of mailing and provide evidence that individual mailpieces have been presented to the USPS for [...]
Manual
Mail.dat Updated Specifications
The USPS released Postal Service Technical Specifications for Mail.dat, Version 2, Release 61, dated December 2, 2024 … (click to [...]