Release Notes
09/24/2026
October 4 2026 - PO! and ProgReg - Release Notes
Announcements
09/24/2026
National PCC Week 2026 PCC Voice Challenge #PCCWeek2026
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09/24/2026
CASS™ Certified Products Guide: Residential Delivery Indicator Cycle O - (Expires July 31, 2028)
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09/24/2026
RDI™ Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)

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

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09/24/2026
CASS™ Certified Products Guide: M L O C R Mailers/Users Data File Cycle O - (Expires July 31, 2028)
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09/24/2026
CASS™ Certified Products Guide: M L O C R Mailers/Users Cycle O - (Expires July 31, 2028)
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09/24/2026
CASS™ Certified Products Guide: M L O C R Service Bureaus Data File Cycle O - (Expires July 31, 2028)
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09/24/2026
CASS™ Certified Products Guide: M L O C R Service Bureaus Cycle O - (Expires July 31, 2028)
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09/24/2026
CASS™ Certified Products Guide: M L O C R Hardware Manufacturers Data File Cycle O - (Expires July 31, 2028)
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09/24/2026
CASS™ Certified Products Guide: M L O C R Hardware Manufacturers Cycle O - (Expires July 31, 2028)
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09/24/2026
CASS™ Certified Products Guide: Z4CHANGE Data File Cycle O - (Expires July 31, 2028)
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09/24/2026
CASS™ Certified Products Guide: Z4CHANGE Cycle O - (Expires July 31, 2028)
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09/24/2026
CASS™ Certified Products Guide: Vendor/Service Licensees Data File Cycle O - (Expires July 31, 2028)
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09/24/2026
CASS™ Certified Products Guide: Vendor/Service Bureaus Licensees Cycle O - (Expires July 31, 2028)
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09/24/2026
CASS™ Certified Products Guide: DSF2® Licensees Data File Cycle O - (Expires July 31, 2028)
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09/24/2026
DSF2® Licensees Cycle O: Certified Products Guide - (Expires July 31, 2028)
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09/24/2026
DPV® Licensees Data File Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)
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09/24/2026
DPV® Licensees Cycle O: Certified Products Guide - (Expires July 31, 2028)
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09/24/2026
CASS™ Software Manufacturers Data File Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)
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09/24/2026
CASS™ Software Manufacturers Cycle O - (Expires July 31, 2028)
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09/24/2026
CASS™/MASS™ Certified Products Guide - All Sections Data Files Cycle O - (Expires July 31, 2028)

This document contains the certified vendors list for CASS™ and MASS™ products for Cycle O.

Announcements
09/23/2026
DELIVERY - International Suspension of Mail Service - Effective September 25, 2026
Announcements
09/22/2026
Update - Central Processing Region - Louisville, KY Processing and Processing and Distribution Center (P&DC)
Announcements
09/22/2026
DELIVERY - Atlantic Area – Maryland District - Hughesville Post Office (20637) - Temporarily Closed
Announcements
09/22/2026
INFORMATIONAL - Commercial System Releases September 24 & 29, 2026