The CASS system improves the accuracy of carrier route, 5-digit ZIP®, ZIP + 4®, and delivery point codes that appear on mailpieces. CASS is offered to all mailers, service bureaus, and software vendors who want to evaluate their address-matching software and improve the quality of their ZIP + 4, CRIS, and 5-digit coding accuracy. This process is graded by the United States Postal Service®, National Customer Support Center (NCSC), and the results returned to mailers in order to provide useful diagnostics for correcting deficiencies.
CASS enables the Postal Service™ to evaluate the accuracy of address matching software programs in the following areas: (1) 5-digit coding, (2) ZIP + 4/ delivery point (DP) coding, (3) carrier route coding, (4) DPV®, (5) DSF2®, (6) LACSLink® (7) eLOT® and (8), RDI™ products. CASS allows vendors/mailers the opportunity to test their address-matching software packages and, after achieving a certain percentage of compliance, to be certified by the Postal Service. CASS does not measure the accuracy of ZIP + 4 delivery point, 5-digit ZIP, or carrier route codes in a mailer's existing files. CASS enables mailers to measure and diagnose internally written, commercially-available, address-matching software packages. The effectiveness of service bureaus' matching software can also be measured.
There are two stages in the CASS process: Stage I, which is optional, and Stage II, which is required for certification.