Ancillary Service Endorsements allow for a sender to obtain an addressee’s forwarding/new address if the addressee has filed a Change-of-Address order with the Postal Service, or a reason for why a mailpiece has not been delivered.

OneCode ACS allows customers mailing First-Class Mail^®, Standard Mail^®, and Periodical flats or letters to receive electronic or automated address corrections using the Intelligent Mail^® barcode.

NCOA is a system of record for all COA requests and is used to produce the NCOA^Link product.  The NCOA^Link Product is a secure dataset of approximately 160 million permanent change-of-address (COA) records constructed from names and addresses of individuals, families, and businesses who have filed a change-of-address with the Postal Service™. Developed with secure data store technology to increase security of postal customer data and protect the privacy of this information, the NCOA^Link Product enables mailers to process mailing lists and update lists with new addresses prior to mailing. The NCOA^Link data is provided on a regular basis to companies that have been licensed by the Postal Service.

The Move Update standard is a means of reducing the number of mailpieces in a mailing that require forwarding or return by the periodic matching of a mailer’s address records with change-of-address orders received and maintained by the Postal Service™. Mailers who claim First-Class Mail^® presorted or automation prices and USPS Marketing Mail™ prices must demonstrate that they have updated their mailing list within 95 days before the mailing date.