Dealing with Undeliverable Mail
April 6, 2023   Karen Bartram

Undeliverable as Addressed mail can be a menace, but USPS Address Correction Service™ (ACS) can help. Learn how SnailWorks can help you to reduce the frequency of your undeliverable mail.

How to Minimize Undelivered Mail for Direct Mail Marketing

Billions of direct mail pieces are returned each year with “undeliverable as addressed” or “UAA” cited as the reason. Direct mail companies and mail owners are all too familiar with undeliverable mail, what can cause it, and how much money can be lost in the process. In addition to losses from the unsent mail pieces, there is now the cost and headache of forwarding or destroying the returned mail. In this blog we will discuss what causes UAA mail and the best ways to minimize the frequency of it.  

What Causes Undeliverable as Addressed (UAA) Mail?

Though most undeliverable mail stems from an issue with the address or physical location, there are many reasons for UAA mail with over 16 different codes from the USPS which are included along with ACS data. Many of these are easy enough to understand from their names, but for clarity, we will briefly explain the more frequently received UAA codes below. If you are responsible for maintaining a mailing list, you will want to make note of these codes and become familiar with their meaning so you can update your list appropriately to prevent repeat incidents and minimize losses.

Not Deliverable as Addressed/Unable to Forward (Q) is the most common reason for undeliverable mail and is usually due to a change of address without a provided forwarding address. If an addressee has moved to a new location without any notification, neither you nor the USPS can do anything about it at that time.

Change of Address (COA) is probably the second-highest reported UAA code that direct mail is returned with. This means that the USPS has been made aware of the new/changed address and that the updated information can be added to your list.

Temporary COA (W) is exactly what it sounds like – the USPS has been notified that the address has been changed temporarily.

Illegible (L) addresses were not written clearly enough or became smudged and otherwise unreadable. This is an easy mistake to correct and prevent in the future.

Box Closed No Order (G) means that a PO box was shut down without a provided forwarding address. Failure to maintain payments is the most common reason for this UAA code.

Unclaimed (U) simply means that the mail remained in the mailbox for an unreasonable amount of time and was retrieved by the USPS.

Deceased (P) means that the intended recipient has passed away and cannot receive the mail.

No Such Street (S) states that your mail was legible, but incorrect, as the address or street does not exist as written.

No Such Number (N) is a UAA code very similar to “No Such Street” and refers to the number of the address.

In Dispute (E) suggests that the undeliverable mail is due to a dispute between postal offices and is likely out of your hands. Make note of the location with the dispute.

No Mail Receptacle (M) is self-explanatory in that there was nowhere to place the mail (that was acceptable by the USPS) and thus could not be delivered.

Refused (R) means that unlike “Unclaimed” mail, this recipient has clearly chosen to return the mail instead of accepting it. This could be due to additional postage charges.

Attempted – Not Known (A) UAA codes mean that the addressee and address do not match. This is very difficult to prevent – even with help from the right software or services – as it is not possible to verify whether someone lives at an address until this code is received.

What is Address Correction Service™ (ACS) and How Does it Work?

Faulty data can cost you a ton in material, labor, mailing, and shipping costs, not to mention with your cash flow and general reputation. Handling UAA mail is also a huge expense for the Postal Service, which is why they offer Address Correction Services to mailers. ACS data leverages work force knowledge from the field as well as the database of change-of-address (COA) requests submitted to the post office by mail recipients.

In most cases mail owners participating in ACS will receive a data file from USPS detailing which pieces were UAA and the reason code for each UAA.  USPS has offered an option to receive manual notifications of ACS updates, however this option will no longer be offered effective July 9, 2023.

How to Benefit From Address Correction Service (ACS)

In most cases USPS offers ACS services free to Full-Service Mailers. Since ACS is a post-production and mailing process the value for mail owners is realized in future mailings when this ACS data is applied to maintained mailing lists.

You do have to have an ACS account with the postal service, and you must request the service on your mailing by including the appropriate Service Type ID (STID) in your barcode. The STID included in the barcode directs the post office on how to handle UAA mail pieces, it is important to understand the ramifications of the services you select as fees may be associated with certain selections.

Why Choose SnailWorks?

While USPS ACS services deliver tremendous value to marketers there are a few technical aspects to setting up and executing a proper ACS strategy and establishing an ACS account with the post office. This is where an expert like SnailWorks can provide insight and value. Additionally, clients who use SnailWorks to manage their ACS data receive easy to understand reports along with standardized data files that have been enriched with mailing information for easy database updates.

After a brief consultation to determine a client’s specific needs, SnailWorks can make recommendations on how to handle ACS updates and establish an appropriate cadence for delivering reports and data.  SnailWorks will also provide guidance on which ACS service to request and which STID to use as well as letting you know when a physical endorsement is needed on the mail piece. Contact us for more information on ACS andhow it can reduce your losses due to undeliverable mail.



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