In cooperation with the mailing industry, the U.S. Postal Service designed Z4Change to provide mailers the information to create an application that would facilitate frequent and cost-effective processing for updating very large computerized mailing lists for automation compatibility and improved deliverability. This joint effort promotes the Industry/USPS® Worksharing Task Force goal of increased use of automation for mail processing.

Current USPS regulations require that all customer address lists be processed by CASS Certified™ address-matching software (see DMM 708.3.3) for a complete description of CASS™ requirements). CASS Certified software applies the correct ZIP + 4®, delivery point, and/or carrier route codes while standardizing the address, city, and state elements. To enhance deliverability, the USPS recommends that customers reprocess their address lists more frequently using CASS Certified software; however, frequent reprocessing of address lists can be costly and time-consuming.

Z4Change was developed for customers who need data as a cost-effective means of improving the deliverability of their mail using the most current ZIP + 4 and delivery point information. Z4Change helps customers achieve this goal by providing data that indicates which ZIP + 4 Codes have been realigned in the past twelve months. When a highrise ("H") or firm ("F") record is added to the ZIP + 4 Product by the USPS, Z4Change also shows a transaction for the supporting street ZIP + 4 Code, allowing customers the opportunity to upgrade previously coded street-level matches. Customers must then develop their own software to access Z4Change to determine which records on their address lists need to be reprocessed by CASS Certified software. As a result, only records that have had transactions will need to be reprocessed, which can be done on a monthly or bimonthly basis.

Should the USPS determine that a significant change in CASS requirements warrants a complete update of all addresses, Z4Change customers may be notified that they will be required to reprocess their entire address lists. Otherwise, Z4Change customers will only be required to reprocess their entire lists at the end of the third year following Z4Change certification.

Z4Change Product and CASS certification offer the following benefits:

• Eliminates the need to reprocess an entire address list by providing a means of maintaining continuous qualification for discounted automation rates. Z4Change users' address files remain current and in compliance with USPS regulations.
• Increases address accuracy by enabling more frequent ZIP + 4 address file processing.
• Enhances the mailer's competitiveness in the marketplace by improving the deliverability of mail and increasing the promptness of mail delivery.

A sample Z4Change file is available for download.