U.S. Postage Rates Take Effect January 18, 2026
January 15, 2026
Make sure you're using the latest edition of AccuZIP6, which includes the January 18, 2026, rate change update.
AccuZIP6 Software Update
https://www.accuzip.com/support/updates
January 18, 2026 Notice 123 Price List Draft from USPS
https://www.accuzip.com/files/pdf/Notice123-Price-Change-Draft-20260118.pdf
Download the latest Mail.dat Support for Production application on January 18 or after:
https://mdx.usps.com/MDRDownload/MDRClient-win64-PROD.zip
AccuZIP6 Technote: Update Mail.dat Support for Production application
https://www.accuzip.com/support/tech-notes/maildat-usps-business-customer-gateway/?id=69
