“Undeliverable As Addressed” (UAA) refers to instances where a postal carrier is unable to successfully deliver mail or packages to the intended recipient. This situation typically arises due to incorrect, incomplete, or illegible addresses, which hinder the carrier’s ability to locate the destination. UAA issues generally inconvenience recipients and have significant financial implications for the mailing industry.
The impact of UAA is staggering, with the mailing industry facing an estimated net loss of $20 billion annually due to undelivered mail. This financial strain arises from several factors, including the cost of returns, re-delivery attempts, and wasted resources spent on processing and handling undeliverable items.
It is crucial to ensure that all mailing addresses are accurate and complete, to overcome UAA challenges. This can involve implementing address verification systems and encouraging recipients to regularly update their information. By addressing the root causes of UAA, businesses can improve their mailing efficiency and enhance customer satisfaction.
What are the Common Reasons for UAA?
Understanding the common reasons for Undeliverable as Addressed (UAA) mail can help businesses and individuals improve their mailing processes and enhance communication effectiveness. Here are the common causes of UAA:

Incorrect or Incomplete Address
An incorrect or incomplete address is one of the leading causes of UAA mail. Typos, such as misspelled street names and missing details like apartment numbers, can disrupt delivery. Even minor errors can lead to significant delays or cause mail to be returned altogether. To prevent these issues, ensure to double-check addresses for accuracy before sending any mail. Utilize address validation tools and encourage recipients to confirm their details. Taking these proactive steps enhances the likelihood of successful deliveries and improves overall communication efficiency.
Recipient Relocation
Frequent relocations by recipients can lead to undeliverable mail, especially if senders are unaware of these changes. To address this challenge, maintaining updated records of recipient addresses is crucial. You can encourage recipients to promptly share their new addresses, making it easier to keep mailing lists accurate. Additionally, implementing an address verification system can significantly enhance delivery efficiency. Such systems validate addresses before sending and flag potential issues, ensuring that mail reaches the right destination.
Address Formatting Errors
Address formatting ensures smooth mail delivery and avoids UAA mail. When an address is formatted inconsistently or incorrectly, it may confuse postal services, leading to delays or returns. For example, using incorrect abbreviations or deviating from local postal guidelines can create significant issues. To prevent such formatting errors, take the time to learn the postal standards specific to your area. Consistency is key, so always ensure that addresses are presented uniformly.
Nonexistent Addresses
Mail sent to nonexistent addresses can pose challenges for senders, but these issues are easily preventable. They often occur when outdated information about new developments is used or an incorrect address is assumed to be valid. These errors lead to UAA mail, consuming time and resources. By proactively verifying addresses with reliable postal databases before mailing, you can ensure your mailing list stays accurate and up to date.
What are the Codes of UAA?
The USPS reports that over 20 UAA codes can appear on returned mail, with each code assigned to specific scenarios where the address or mail cannot be delivered. While some UAA codes are clear and easy to understand, others can be complex.
To help you navigate this, here is the list and explanation of all the major UAA codes:
Not Deliverable as Addressed/Unable to Forward
These return mail types are among the most common. If the code indicates “Not Deliverable as Addressed” or “Unable to Forward,” it signifies that the recipient has either moved from that address or that the address on the mail piece does not match the available data.
Since the recipient has not requested a mail forwarding service to their new address, the USPS lacks information on the new location and is not obligated to deliver it. The return codes 23 or 27 from CASS or NCOALink are used in such cases.
Insufficient Address
When the UAA code indicates “Insufficient Address,” the address on your mail piece lacks vital information needed for delivery. Crucial details include elements like a PO Box number, a city name that may be missing or incorrect, a street address without a house number, or an absent or incorrect ZIP code.
Regardless of how effective your mailing service is for your business’s direct mail; incomplete addresses hinder delivery. You can identify such incomplete addresses by checking for return codes ranging from 10-17 using CASS or NCOALink.
Attempted – Not Known
When you encounter the UAA code “Attempted – Not Known” on a returned mail piece, it indicates that the addressee listed is either unknown or no longer resides at the address provided. This code is one of the more challenging UAA issues to address before mailing, even when utilizing advanced address verification tools. Unfortunately, neither NCOALink nor CASS can confirm whether a specific individual currently lives at a particular address.
While it is possible to identify if a resident has moved from an address, it is not feasible to ascertain whether someone has never lived there or has recently relocated. To ensure the accuracy of your address data’s accuracy, obtaining information from a reliable source is essential.
No Mail Receptacle
As the name implies, this UAA code applies when a mail piece lacks an acceptable mail receptacle as defined by the USPS. A prime example is gated communities that utilize a centralized mail center instead of individual mailboxes in front of each home.
For instance, if you want to send mail to 1408 Walls Street, the USPS can only deliver it directly to that address if there is a mailbox. If a mailbox is not present at the address, the mail must be routed to the 1408 Walls Mail Center. In these situations, the USPS often flags the delivery with a phantom route CRRT of R777.
No Such Number
This UAA code pertains to the essential numbers in an address. The number included on your mail piece may not correspond to a valid address on that street. This is a common UAA issue, as it is easy to mix up numbers unintentionally. However, that’s not always the case. Sometimes, the number simply falls outside the specified range for that street. If that occurs, you will receive return code 21 from CASS.
Returned for Better Address
Another common UAA code arises when the address on your mail piece is insufficient for USPS personnel to complete the delivery. A more accurate address for the recipient or location exists in many cases. The USPS assigns an Undesirable Return Code to these addresses after processing through CASS and NCOALink.
Illegible
To ensure successful delivery, write addresses on mail pieces in a clear, easily readable font. Your mail gets sorted by either a postal sorting machine, USPS staff, or both, so maintaining good readability is crucial. To enhance legibility, consider the label design carefully and choose a font that is easy for USPS to read. Doing this significantly reduces the chances of your mail being undeliverable due to illegibility.
Outside Delivery Limits
The post office handling an addressee’s mail can sometimes change, causing postal mail to be sent to the original post office to cover the recipient’s current address no longer. USPS updates this information regularly, typically every month. Consequently, the post office responsible for the address may have changed since the last update. This UAA issue can also occur if you mistakenly write down the incorrect city name. Sometimes, even if the recipient’s residence is technically in a specific city, a different post office may manage the postal mail.
Returned for Postage
Postage is the essential ticket allowing mail pieces to travel from point A to point B. With postage, your direct mail can be delivered. If a mail piece lacks postage or shows no sign of having had postage applied, it will be returned to you. To prevent this situation, consider using printed indicia for your mail pieces. However, be aware that production issues might delay or disrupt indicia printing. Taking these proactive steps will help ensure the successful delivery of your mail.
Moved, Left No Address
This UAA code indicates that the addressee has moved from their previous address without submitting a Change of Address (COA) form. In these instances, the USPS recognizes that the addressee no longer resides at that location, but they lack the information to forward the mail. You can utilize the Proprietary Change of Address (PCOA) tool to navigate this situation effectively. Most likely, the individual has updated their address with the businesses they frequently interact with, allowing you to retrieve the correct mailing information.
Temporarily Away
The Temporarily Away UAA code applies when the addressee is not present at their residence but still considers it their primary home. This situation also arises when the addressee’s temporary forwarding or mail-holding order has expired. In these cases, NCOALink may report it as a temporary move.
Refused
Sometimes, the addressee may choose not to accept the mail or decline to pay the additional postage due. These instances fall under the UAA code “Refused.” To minimize such occurrences, ensure that your mail has adequate postage. However, it is important to note that a recipient can still refuse to accept the mail even with sufficient postage.
Vacant
When a postal address on your mail piece is unoccupied, it is classified as “Vacant.” The DPV vacant field flags these cases, which are returned through CASS or NCOALink.
Box Closed – No Order
When a PO Box is closed without a forwarding address and postal mail is sent to that box, the USPS applies this UAA code. This situation typically arises when the PO Box is closed due to non-payment. Mail pieces affected by this issue are returned with a code of 26 from NCOALink.
Unclaimed
When postal mail remains in the receptacle for an extended period, the mail carrier may retrieve it, marking it as “Unclaimed.” In these situations, the mail is returned to the sender, even though the address is correct. This issue often stems from poor data quality, highlighting the importance of timely mail collection.
Deceased
This UAA code is straightforward; it is used when the addressee has passed away. You can easily filter out these addresses using an advanced address verification tool and promptly remove them from your database.
Returned to Sender due to Addressee’s Violation
This situation arises when the addressee violates a postal order or rule, often involving false representation. While various circumstances may lead to this issue, the solution is straightforward: remove the address from your database. By doing so, you can prevent future mailings to the addressee and ensure compliance with postal regulations.
In Dispute
This situation arises when postal officials disagree about the delivery of direct mail to a specific location. Local authorities may have valid reasons for withholding delivery, but the case has not yet been confirmed or entered into the CASS system.
No Such Office in
When you encounter this UAA code, it indicates that the Post Office meant to service the mail piece does not exist. This situation often arises from outdated labeling lists that are valid for two months. Additionally, a new set of labeling lists has likely been published by this time.
State No Such Street
This UAA code indicates that the street name provided in the non-standard address does not exist. The return codes associated with this issue are 10 or 17 from CASS.
How does UAA Impact Different Types of Mail?
Undeliverable As Addressed (UAA) mail can have significant consequences across different types of mail. Here is the explanation of how it impacts:
Personal Mail
UAA can lead to missed letters, gifts, or essential documents, such as legal notices or bills. When personal mail is undeliverable, it can lead to frustration for both the sender and the intended recipient. Missed communication, lost sentimental items, or delayed important documents can result in confusion or missed opportunities. To avoid these issues, individuals should double-check addresses before sending personal mail, especially when mailing sensitive or valuable items.
Business and E-commerce
UAA mail can cause customer dissatisfaction, costly delays, and increased shipping expenses for businesses. E-commerce companies face higher return rates and restocking fees when products are returned due to incorrect or outdated addresses. It affects customer service and also impacts profitability. Delivery issues affect customer trust and can impact future business. By implementing address verification systems and encouraging customers to update their information, businesses can enhance customer satisfaction and avoid unnecessary re-shipping and return costs. These proactive steps help build trust, improve the customer experience, and ensure smoother operations.
Marketing Campaigns
UAA mail can affect marketing campaigns by redirecting resources, but addressing accuracy improves outreach efficiency and maximizes campaign success. When businesses conduct mass mailings for promotional purposes, undeliverable mail can lead to missed opportunities for customer engagement. Each piece of undeliverable mail represents a potential lost sale or interaction. Moreover, printing and mailing costs associated with UAA mail add up quickly, reducing the return on investment (ROI) of the campaign. Addressing UAA mail in marketing campaigns is essential to ensure better results, improve engagement rates, and maximize the effectiveness of promotional efforts.
How to Avoid UAA?
To avoid UAA mail, you can implement several effective strategies to ensure accurate delivery. Here are some practical steps to prevent UAA and improve the efficiency of your mailing process:

Double-Check Information
Always verify the recipient’s details before sending mail. Simple errors, such as a missing apartment number or a typo in the street name, can result in UAA. You can significantly reduce the chances of undelivered mail by thoroughly reviewing each address. This step is crucial when dealing with bulk mail or business correspondence.
Use Correct Formatting
Following postal service guidelines for proper address formatting are essential in preventing UAA. Different regions may have specific formatting rules, including the use of abbreviations, proper placement of elements (such as ZIP codes), and correct address structure. Using the right format ensures that the postal system can efficiently process and deliver your mail. You can consistently adhere to these guidelines minimizing the risk of delays or returns.
Postal Address Verification Tools
Businesses can utilize address verification software to prevent UAA issues. These tools automatically check the accuracy of recipient addresses against postal databases before mail is sent out. This technology helps businesses maintain up-to-date mailing lists and avoid sending mail to incorrect locations by flagging invalid or incomplete addresses. Postal verification tools improve delivery accuracy and save time and resources by reducing the need for manual corrections.
Include Return Addresses
Including a return address on every mail piece is essential for handling undeliverable mail. If the recipient’s address is incorrect or the mail cannot be delivered, the return address ensures the item will be returned to you. This allows you to resolve the issue quickly, such as updating the recipient’s details or forwarding the mail to a new address. If there is no return address, undeliverable mail may be discarded or lost, wasting time and resources.
What Happens After a UAA Event?
After a UAA event, the postal service takes specific steps to manage the undelivered mail, ensuring that the item is handled properly. Here’s what generally happens:
Return to Sender
If the postal service determines that the address provided is incorrect or incomplete and forwarding isn’t available, the mail is usually returned to the sender. This process includes marking the envelope or package with a reason for non-delivery (such as “insufficient address” or “recipient moved”) and then sending it back. This is a significant opportunity for businesses to update their mailing records to prevent future UAA events.
Held at Postal Facility
In some cases, if the mail cannot be delivered immediately, it may be held at the local postal facility. This is common with packages or certified letters that require a signature. The postal service usually notifies the recipient, allowing them to pick it up within a designated time. If unclaimed, the item might be returned to the sender after the holding period expires. Businesses or individuals expecting critical mail should monitor their local post office for notifications to avoid delays.
Forwarding (if applicable)
When forwarding instructions or a post office box is associated with the recipient, the USPS forwards the mail to the new or temporary address. This is common when recipients move or provide a forwarding address to the post office. In this case, mail can reach its destination without being returned to the sender, ensuring a smooth process. Maintaining updated forwarding instructions or using P.O. boxes helps avoid UAA events and improves delivery success.
Steps to Take if Your Mail is Marked as UAA
If your mail is marked as UAA, you can take a few simple steps to resolve the issue and ensure your mail reaches its destination:

Contact the Postal Service
The first step is to contact your local post office or the USPS customer service line. Be sure to have important details ready, such as the tracking number, correct recipient address, and any other relevant information about the package or letter. The postal staff can help you understand why your mail was undeliverable and guide you on the next steps.
Resend with the Correct Address
Once you have identified the issue, correct the address to fix it. You should double-check for common errors like incorrect street names, missing apartment numbers, or incomplete ZIP codes. After verifying that the address is accurate, resend the mail. This simple step increases the likelihood of successful delivery on the next attempt. If possible, use address validation tools to ensure accuracy before sending the item again.
Request for Forwarding
If the recipient has moved, request mail forwarding. The USPS offers a forwarding service to send mail to the recipient’s new address if they have submitted a ‘Change of Address’ form. While this service may not apply in every case, it is a valuable option to explore. Ensuring that the recipient’s current address is on file improves the chances of your mail reaching its intended destination.
Enhance Delivery Success with Compu-Mail’s Mailing Solutions
Verifying and properly formatting addresses is essential to avoid delivery issues. Compu-Mail simplifies this process by offering comprehensive mailing services that enhance accuracy. With advanced address verification tools and strict adherence to postal standards, Compu-Mail helps businesses significantly reduce the risk of Undeliverable as Addressed (UAA) mail. Eliminating common errors like incorrect or incomplete addresses ensures smoother and more reliable mail delivery.
Partnering with Compu-Mail saves time and resources and boosts customer satisfaction by promptly ensuring your communications reach the right recipients. When you trust Compu-Mail’s expertise, you can feel confident that your mail is handled precisely, minimizing delivery problems and strengthening connections with your audience.
FAQs
Q: What does not deliverable as addressed mean?
A: “Not Deliverable as Addressed” means the postal service could not deliver the mail because the address provided was incorrect or incomplete.
Q: What happens when mail is undeliverable as addressed?
A: The postal service attempts to return it to the sender or forwards it if a forwarding address is available. This helps ensure that the mail either reaches the correct recipient or alerts the sender to update the address.
Q: Why does it say my address may not be deliverable?
A: Your address may be undeliverable due to missing details, incorrect formatting, or outdated information. Verifying and updating your address ensures it meets postal standards for smooth delivery.
Q: What does USPS do with undeliverable packages?
A: USPS either attempts to return them to the sender, forwards them to the recipient’s new address if possible, or holds them for pickup if the address is incomplete or incorrect.
Q: How long does it take for USPS to return undeliverable mail?
A: USPS typically returns undeliverable mail within 7 to 14 days, depending on the specific conditions and the type of mail involved.
Q: Does USPS destroy undeliverable mail?
A: The United States Postal Service (USPS) can dispose of undeliverable mail through its Secure Destruction program.
Q: Where can I pick up my undelivered mail?
A: If you are inquiring about undelivered mail from the United States Postal Service (USPS), you can collect it at your local post office.
Compu-Mail, LLC
Compu-Mail, LLC is a leading provider of secure communications, direct mail, omnichannel marketing, commercial print, and promotional products. Since 1983, Compu-Mail has helped organizations achieve...
Compu-Mail, LLC is a leading provider of secure communications, direct mail, omnichannel marketing, commercial print, and promotional products. Since 1983, Compu-Mail has helped organizations achieve their communication goals through innovative technology, data-driven strategies, and a steadfast commitment to compliance. The company maintains SOC 2 Type II, SOC 3, HIPAA-Certified Facility, PCI-DSS, USPS Election Mail, G7, and HITRUST certifications, ensuring the highest standards of security, quality, and operational excellence. Compu-Mail writes about direct mail, compliance, data security, postal regulations, and marketing strategies that drive results.



