Ancillary Service Endorsements

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.

Who are Ancillary Service Endorsements for?

Ancillary Service Endorsements are for mailers looking to obtain updated addressee information.

First Class Mail

First Class Mail





Standard Mail

Standard Mail

Stay Compliant with Move Update


What are Ancillary Service Endorsements?

Ancillary Service Endorsements allow the sender to obtain the addressee's new (forwarding) address (provided the appropriate endorsement is used and if the addressee filed a Change-of-Address Order with the Postal Service) or the reason for non-delivery.

Undeliverable-as-addressed (UAA) mail is forwarded, returned to sender, or discarded as authorized for the particular mail class. A mailer endorsement is used to instruct the Postal Service regarding the appropriate disposition upon determining that it is UAA. A return address is required on the face of the mailpiece when using ancillary service endorsements. The following endorsements may be used as an updating method to meet the Move Update standards for First-Class Mail®, USPS Marketing Mail™, and Parcel Select Lightweight® mail.

Change Service Requested

Separate notice of new address or reason for non-delivery provided; in either case, address-correction fee is charged; mailpiece is not forwarded or returned, but discarded by the Postal Service. NOTE: This endorsement is not available for First-Class Mail unless used in conjunction with electronic ACS™. 

Address Service Requested 

Mail is forwarded if possible, or returned if forwarding is not possible. A separate notice with new address information is provided for forwarded pieces and the address-correction fee is charged. First-Class Mail is forwarded or returned at no charge. USPS Marketing Mail is charged the weighted fee for mail that must be returned. The Weighted Fee is equal to the single-piece First-Class price multiplied by 2.472 (a one ounce letter is charged 63¢ x 2.472 = $1.557, rounded-up to $1.56).

  • Months 1 - 12: the mailpiece is forwarded; no charge; a separate notice of the new address is provided.
  • Months 13 - 18: the mailpiece is returned with the new address attached.
  • After month 18 or if undeliverable at any time: the mailpiece is returned with reason for non-delivery attached.

Return Service Requested

If UAA, the mailpiece is returned with the new address or reason for non-delivery. First-Class Mail is returned at no charge. USPS Marketing Mail and Parcel Select Lightweight mail is returned at either the single-piece First-Class Mail or Priority Mail price, depending on the weight of the piece.

Temp-Return Service Requested

This endorsement option is available for First-Class Mail only. This endorsement is similar to Return Service Requested, however if the change-of-address is temporary, the piece will be forwarded to the temporary address. The temporary address information is not provided to the mailer. If there is a permanent change-of-address, the mail piece is handled the same as Return Service Requested.


Ancillary Service Endorsement Authorized Locations

Ancillary service endorsements may be placed under the return address, above the delivery address block, to the left of the postage area, or below the postage area (postage stamps, meter stamps, or permit imprints).

Featured Resources

Domestic Mail Manual (DMM®) 507.1.0: Treatment of Mail

This document provides information on treatment of mail.

Ancillary Services for Parcel Select and Parcel Select Lightweight FAQs

Frequently Asked Questions for Ancillary Services for Parcel Select and Parcel Select Lightweight

Related Products


ACS is a post mailing service that allows mailers to receive change-of-address (COA) and other reasons for non-delivery electronically and reduce the number of manual (hardcopy) address notifications.

Move Update

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, USPS Marketing Mail™ prices, and Parcel Select Lightweight® prices must demonstrate that they have updated their mailing list within 95 days before the mailing date.

99% Testing

The 99% Accurate test is a computer-based process that performs Postal Service ZIP + 4® coding and change-of-address processing utilizing the customer’s file as input. The 99% Accurate test is accomplished by submitting the mailer’s address file(s) to the Postal Service for processing.


For more information about the Ancillary Service Endorsements process, contact Address Improvement and Administrative Support at 800-238-3150.