Announcements
07/02/2026
INFORMATIONAL: USPS APIs System Deployment - July 11, 2026
Announcements
07/02/2026
INFORMATIONAL: USPS APIs System Deployment - July 19, 2026
Announcements
07/02/2026
DELIVERY: WestPac Area: CO-WY District - Temporarily Closed - Wetmore Post Office (81253)
Data Files
07/02/2026
Undeliverable-as-Addressed (UAA) Statistics by Mailing Industry Quarterly Report (Q3 FY26)

ACS Nixie stats by industry for FY26 Q3.

Announcements
07/02/2026
INFORMATIONAL: Commercial System Releases - July 11 – July 17
Release Notes
07/02/2026
July 12 2026 Release Notes
Contact Lists
07/02/2026
CASS™ Certified Products Guide: Residential Delivery Indicator Cycle O - (Expires July 31, 2028)
Contact Lists
07/02/2026
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
07/02/2026
CASS™ Certified Products Guide: M L O C R Mailers/Users Data File Cycle O - (Expires July 31, 2028)
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07/02/2026
CASS™ Certified Products Guide: M L O C R Mailers/Users Cycle O - (Expires July 31, 2028)
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07/02/2026
CASS™ Certified Products Guide: M L O C R Service Bureaus Data File Cycle O - (Expires July 31, 2028)
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07/02/2026
CASS™ Certified Products Guide: M L O C R Service Bureaus Cycle O - (Expires July 31, 2028)
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07/02/2026
CASS™ Certified Products Guide: M L O C R Hardware Manufacturers Data File Cycle O - (Expires July 31, 2028)
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07/02/2026
CASS™ Certified Products Guide: M L O C R Hardware Manufacturers Cycle O - (Expires July 31, 2028)
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07/02/2026
CASS™ Certified Products Guide: Z4CHANGE Data File Cycle O - (Expires July 31, 2028)
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07/02/2026
CASS™ Certified Products Guide: Z4CHANGE Cycle O - (Expires July 31, 2028)
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07/02/2026
CASS™ Certified Products Guide: Vendor/Service Licensees Data File Cycle O - (Expires July 31, 2028)
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07/02/2026
CASS™ Certified Products Guide: Vendor/Service Bureaus Licensees Cycle O - (Expires July 31, 2028)
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07/02/2026
CASS™ Certified Products Guide: DSF2® Licensees Data File Cycle O - (Expires July 31, 2028)
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07/02/2026
DSF2® Licensees Cycle O: Certified Products Guide - (Expires July 31, 2028)
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07/02/2026
DPV® Licensees Data File Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)
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07/02/2026
DPV® Licensees Cycle O: Certified Products Guide - (Expires July 31, 2028)
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07/02/2026
CASS™ Software Manufacturers Data File Cycle O: Certified Products Guide (D) - (Expires July 31, 2028)
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07/02/2026
CASS™ Software Manufacturers Cycle O - (Expires July 31, 2028)
Contact Lists
07/02/2026
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.