The Coding Accuracy Support System (CASS) improves the accuracy of carrier route, five-digit ZIP, ZIP+4, and delivery point codes that appear on mail pieces. The encoding process performs the following procedures:

• Edit and parse the address file to be matched. Parsing requires that the individual elements that make up an address are isolated, edited, and standardized. Parsing includes:

  • separating the individual words of the address (ZIP Code, street name, suffix, directionals, etc.) based on spaces, commas, periods, colons, other delimiters, or field position

  • distinguishing elements such as apartment, suite, room, etc. and placing them in a secondary address field placing company names, building names, or other secondary information in a secondary name field

  • standardizing the state field as shown in the Postal Addressing Standard, Publication 28 or the AIS Product Technical Guide

• Convert numeric street primary names from alphabetic spelling to numeric equivalent.

• Standardize the street suffix field to conform to USPS suffixes.

• Standardize directionals to conform to USPS directionals.

• Correct spelling of city names.