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Undeliverable As Addressed Mail: Where Does It Come From, and How Do You Fix It?

Written by Gary A. Seitz

This article was originally published by Mailing Systems Technology.

The Problem
. We’ve all seen it: trays and bins of mail with those bright yellow stickers returned to our office. It’s embarrassing as management seeks out to answer why the organization is getting so much returned mail.

The USPS defines Undeliverable As Addressed (UAA) mail as all mail that cannot be delivered to the name and address specified on the mail piece and must be forwarded, returned, or treated as waste as authorized for the class of mail and ancillary service endorsement on the mail piece. It may be due to individual, family, or business moves, incomplete or incorrect addresses, unknown or deceased addresses, lack of a delivery receptacle, refusal by the recipient, or lack of sufficient postage.

In 2015, the USPS handled almost 6.5 billion pieces of UAA mail, forwarding 994 million pieces, treating four billion pieces as waste, and returning 1.4 billion pieces that alone cost the USPS $788 million. Even though mail volume is decreasing, UAA mail remains a significant problem.

For mailers, this also means wasted costs (industry estimates are one to three dollars per piece in operational costs) including lost and delayed revenue, reduced customer satisfaction and marketing opportunities, and lost customers.

Why is so much mail undeliverable? The primary reason is that over 75% of the recipients no longer receive mail at the address — simply, they’ve moved. Another 12.5% have missing or incorrect address elements (usually a secondary address like apartment/suite number), and another eight percent are destined to vacant addresses.

The USPS has found that of the 75% of UAA mail that is related to “move updates,” 60% have moved within the prior three months. In most cases, this can simply be due to the amount of time between when mailers select names from their customer databases and when the mail is prepared and delivery is attempted to the address on file.

Basic solutions. The USPS promotes the “3 Cs” for effective address hygiene: correct, complete, and current.

For correct addresses, it all begins at the point of capture. Modifying entry screens (including your website) and implementing training procedures on collecting and entering proper addresses (we’re proponents of USPS Pub 28) is a start. Apply CASS and LACS updates to your file at least quarterly. CASS/DPV validates the specific accuracy of ZIP Codes, street names, house numbers, and secondary addresses. Then identify records that do not match up with CASS/DPV for correction. A few tools for address correction are reviewed later in this article. LACS updates addresses that changed due to local community address conversions or 9-1-1 implementation in rural areas. These include both street name changes and address renumbering (yes, your house can actually be renumbered!).

Complete addresses include SuiteLink and Apartment Append. Adding or correcting missing secondary address information improves NCOA matching, duplicate elimination, and address delivery. SuiteLink is available during CASS processing, and many service providers offer Apartment Append.

Keep addresses current by utilizing NCOA (either 18-month or 48-month), and periodically utilize Ancillary Service Endorsements and the ACS program (we recommend at least twice each year). We highly recommend mailers utilize NCOA quarterly on their master files and immediately prior to any mailing. The USPS Vacant File is also a valuable add-on to CASS. Maintained and updated monthly by USPS carriers, this file will flag addresses that have been vacant and without mail delivery for at least 90 days.

Surprisingly, capturing customer name information is a valuable component to address hygiene. Check your database for proper formatting for first and last name. Don’t mix data fields by including business titles in the name field, or span personal or company name data in your address fields. Name fields are used for postal matching in NCOA, and extraneous data in the address field may cause your mail to become UAA.

Ensure you have sufficient space in your database for addresses. Thirty to 50 characters is the new norm. Specify a separate field for secondary address information like apartment or suite; it serves as a reminder to enter it. This should be for any internal system as well as your website. Entry staff should be trained on all proper address elements and abbreviations. Again, Publication 28 (available on the website) is a great training resource.

Some advanced solutions. Have some addresses that just won’t match? Print out some records on your database that don’t have a Zip+4 Code assigned to them for review. You’ll be surprised and amused by some of the problems. These include “run-ons” (124SouthMill), extra digits (100000 Euclid), invalid abbreviations (17 So Watt St or 492 Jackson Bl), misplaced secondary addresses (47 #A Cedar Rd), or random characters (5!7 M0ss St).

The USPS offers an excellent set of tools for problematic address resolution. Address Element Correction (AEC) uses advanced address matching based on USPS-developed algorithms. It typically resolves about 30% of addresses you provide at a cost of less than $25 per thousand addresses provided.

AEC’s big brother AEC II uploads unresolved AEC addresses to local delivery offices for Delivery Force Knowledge (i.e. carrier) resolution at of cost of $.31 per resolved record.

ACS is a post-mailing address correction service that allows mailers to receive change-of-address and other reasons for non-delivery electronically. ACS is available for all classes of mail and is used in combination with Ancillary Service Endorsements. Full-Service IMB mailers can obtain this data at no charge in some cases.

Unfortunately, not everyone who moves notifies the USPS. In fact, the USPS estimates that nearly 40% of movers never file a COA with the Postal Service! How do you locate these people (who may be some of your most valuable customers)? Many Mail Service Providers (MSPs) offer a Proprietary Change of Address service compiled from third-party sources, including magazines, catalogers, utilities, and financial institutions. Your entire file can be “scrubbed” against these files, or you can provide the data from your most recent batch of returned mail. You may be pleasantly surprised by the results!

In Conclusion. Be aware of the impact of your UAA mail. You’re not alone. It’s an industry-wide problem. It’s important that everyone in the mailing industry makes effective delivery of mail and reduction of UAA mail their goal. Your MSPs and the USPS both have tools to assist you in reducing your UAA mail. Don’t be afraid to call them and ask for their advice and assistance.

Gary A Seitz is Vice President of CTRAC Direct and has been a frequent presenter on UAA mail at the NPF and PCCs around the country for over 30 years. Gary can be reached at or by calling 216.251.2500 x 4985. This article is based on material presented in a session at the 2016 NPF by Gary A Seitz and Jim Wilson of the Address Management group of the US Postal Service.

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