Address Change Service (ACS™)
An automated address correction process that provides to participating mailers a data file containing change-of-address and undeliverable-as-addressed information. ACS is used in conjunction with Ancillary Service endorsements Change Service Requested and Address Service Requested. Three ACS products are available: (a) traditional ACS, in which the mailer modifies the address block to include an ACS Participant Code (#B) and optional keyline; (b) OneCode ACS, in which the mailer requests ACS using the Intelligent Mail barcode; and (c) Full Service ACS, in which the mailer uses the Intelligent Mail barcode and also presents mail that qualifies for Full Service discounts. Fees charged for ACS vary by mail class, mail shape, and mail product.