USPS to retire the manifest mailing system (MMS) effective April 1, 2026
March 26, 2026
The USPS is amending Mailing Standards of the United States Postal Service, Domestic Mail Manual (DMM) subsection 703.2.0 to retire the manifest mailing system (MMS). Effective April 1, 2026.
Non-Seamless Mailers mailing Cards, Letters or Flats
- Mailers using MT or PC permit types with Mail.dat/Mail.XML should contact software vendor for instructions on removing the “batch” or “itemized” Mailing Agreement Type from their submissions
- Mailers using MT or PC permit types with Postal Wizard – Discontinue selection of the Special Postage Payments System options for Batch and Itemized manifests. Leave the SPPS option as “NONE”
- Mailers using PI permits with an identical piece weight with Mail.dat/Mail.XML should contact software vendor for instructions on removing the “batch” or “itemized” Mailing Agreement Type from their submissions
- Mailers using PI permits with an identical piece weight using Postal Wizard – Discontinue selection of the Special Postage Payments System options for Batch and Itemized manifests. Leave the SPPS option as “NONE”
- Mailers using PI permits with non-identical piece weights must convert to Seamless by 4/1/26 to continue mailing these types of mailings
All Mailers Mailing Parcel Mailings
- Mailers identifying a piece weight and using Mail.dat/Mail.XML should contact software vendor for instructions on removing the “batch” or “itemized” Mailing Agreement Type from their submissions
- Mailers identifying a piece weight and using Postal Wizard – Discontinue selection of the Special Postage Payments System options for Batch and Itemized manifests. Leave the SPPS option as “NONE”
- Mailers using non-identical pieces weights must convert to USPS Ship or Click-N-Ship by 4/1/26 to continue mailing these types of mailings
Seamless Mailers Mailings Letter, Cards, or Flats
- Seamless mailers using Mail.dat/Mail.XML should contact their software vendor for instructions on removing the “batch” or “itemized” Mailing Agreement Type from submissions.
- Seamless mailers using Postal Wizard – Discontinue selection of Special Postage Payments System options for Batch and Itemized manifests. Leave the SPPS option as “NONE”
