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The CASS certification process is designed in cooperation with the mailing industry to improve the accuracy of postal codes, i.e., 5-digit ZIP Code

®, ZIP + 4®, delivery point (DPCs), and carrier route codes that appear on mailpieces.

The CASS software certification program

provides hardware and software developers, service bureaus, and commercial mailers a common measure by which to test the quality of address-matching software. Software tests for CASS certification are graded by the U.S. Postal Service® National Customer Support Center (NCSC), and the results are returned to the developer to provide useful diagnostics for correcting software deficiencies. However, CASS processing does not measure the accuracy of ZIP + 4, delivery point, 5-digit ZIP Code, or carrier route codes in a mailer’s address file.

CASS certification is valid until the end of the current biennial period. For software to remain CASS Certified for each biennial period, developers must reapply for certification and meet the minimum accuracy requirements during Stage II testing.

Another certification program offered by the CASS Department is MASS. MASS is an extension of CASS, which is a process designed in cooperation with the mailing industry to improve the accuracy of postal codes that appear on mail.

MASS provides certification for MLOCRs, (Multiline Optical Character Readers), RVE (Remote Video Encoding) systems, LVE (Local Video Encoding), and encoding stations to process address information and apply an accurate delivery point barcode (DPBC).

The NCSC issues MASS certification once the required level of accuracy is achieved. MASS certification is a biennial requirement and is valid from the certification date until the end of any current biennial period. MASS certification is required for all mailers using MLOCRs, RVE systems, LVE or encoding stations when printing DPBCs on mailpieces that are to be submitted for mailing at discounted automation rates.

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Important Updates

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Coming Soon: PostalPro

The RIBBS website has been redesigned and is in the process of transitioning to a new home called PostalPro. www.postalpro
will become the primary source for USPS mailing information.

PostalPro leverages powerful search functionality, intuitive navigation, and a modernized, mobile-friendly design.

Upcoming 2017 Releases

Upcoming 2017 Releases

January 2017 Price Change Fact Sheet

January 2017 Release Overview

January 2017 Release Notes

Market Dominant Pricing Files

Click here for weekly Incorrect Scanner Configuration Report

Click here for 2015 Network Consolidations

Click here for Mail Processing Current and Future Operating Plan

Click here for Network Rationalization Service Standard Analysis

Click here for Plants with Remittance Mail Documents

Click here for Customer Letter regarding 2015 Network Consolidations

Click here for the new Service Type ID information page

Service Hub Facilities

Service Hubs – Mail Prep and Entry

Presort Reference Data Issue Log

FAST Label List Test Data

FAST Enhancements September 25, 2016

IV Migration Overview

Getting Started with Full-Service Intelligent Mail

PostalOne! Contingency Plan

For mailers unable to submit electronic information, click here for the PostalOne! Contingency Plan.


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