Announcements
05/29/2026
Processing and Distribution - Memphis TN Regional Processing and Distribution Center (RPDC) Expands Operations May 30, 2026
Announcements
05/29/2026
Processing and Distribution - UPDATE - Western Region – Tucson, AZ Processing and Distribution Center (P&DC) - Power Restored
Announcements
05/28/2026
DELIVERY - Diplomatic Post Office (DPO) May 28, 2026
Tech Guides
05/28/2026
USPS Ship Zone Tech Sheet
Release Notes
05/28/2026
PTR2 Release Notes_DD_05_30_26
Applications/ Forms
05/28/2026
Mailers Technical Advisory Committee (MTAC) Association Membership Form
Applications/ Forms
05/28/2026
Mailers Technical Advisory Committee (MTAC) Association Membership Form
Contact Lists
05/28/2026
CASS™ Certified Products Guide: Residential Delivery Indicator Cycle O - (Expires July 31, 2028)
Contact Lists
05/28/2026
RDI™ Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)

This document outlines the CASS/MASS certified vendors list for RDI™ Cycle O.

Contact Lists
05/28/2026
CASS™ Certified Products Guide: M L O C R Mailers/Users Data File Cycle O - (Expires July 31, 2028)
Contact Lists
05/28/2026
CASS™ Certified Products Guide: M L O C R Mailers/Users Cycle O - (Expires July 31, 2028)
Data Files
05/28/2026
Population Mobility Trends 12-Month Historical (CSV) Sample File
Contact Lists
05/28/2026
CASS™ Certified Products Guide: M L O C R Service Bureaus Data File Cycle O - (Expires July 31, 2028)
Contact Lists
05/28/2026
CASS™ Certified Products Guide: M L O C R Service Bureaus Cycle O - (Expires July 31, 2028)
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05/28/2026
CASS™ Certified Products Guide: M L O C R Hardware Manufacturers Data File Cycle O - (Expires July 31, 2028)
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05/28/2026
CASS™ Certified Products Guide: M L O C R Hardware Manufacturers Cycle O - (Expires July 31, 2028)
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05/28/2026
CASS™ Certified Products Guide: Z4CHANGE Data File Cycle O - (Expires July 31, 2028)
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05/28/2026
CASS™ Certified Products Guide: Z4CHANGE Cycle O - (Expires July 31, 2028)
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05/28/2026
CASS™ Certified Products Guide: Vendor/Service Licensees Data File Cycle O - (Expires July 31, 2028)
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05/28/2026
CASS™ Certified Products Guide: Vendor/Service Bureaus Licensees Cycle O - (Expires July 31, 2028)
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05/28/2026
CASS™ Certified Products Guide: DSF2® Licensees Data File Cycle O - (Expires July 31, 2028)
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05/28/2026
DSF2® Licensees Cycle O: Certified Products Guide - (Expires July 31, 2028)
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05/28/2026
DPV® Licensees Data File Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)
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05/28/2026
DPV® Licensees Cycle O: Certified Products Guide - (Expires July 31, 2028)
Contact Lists
05/28/2026
CASS™ Software Manufacturers Data File Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)