One of the challenges of participating in the Seamless Acceptance program is dealing with undocumented mail piece errors. The assessments for these errors can be quite expensive. Unlike some of the other assessments that are passed onto the respective mail owners, assessments for undocumented pieces will usually come right out the mail preparers’ pockets. It is often difficult for mail preparers to pinpoint the source of these errors to either correct the issue or to provide documentation to the USPS to dispute the error.

What Is an Undocumented Mail Piece?

An undocumented piece is one with an Intelligent Mail barcode (IMb) that has been scanned by USPS Mail Processing Equipment (MPE), but it can’t be associated with any eDoc. For validation purposes, the USPS checks against the eDoc Submitter Customer Registration ID (CRID) and submissions within the last 45 days. The current error threshold is .3%; however, mail preparers must explain any errors over the .1% level. The mail piece barcode data is populated in your eDoc during the presort process, whether you’re using presort software or a multiline optical-character reader (MLOCR). So, what causes these undocumented mail pieces, and how can mail preparers prevent this issue?


One common cause is regenerating Mail.dat files after the barcodes have been printed on the mail pieces. While this may be necessary for a variety of reasons, it is critical to make sure that when these files are regenerated, new IMbs are not being generated. To prevent undocumented pieces, having QA procedures in place to verify that the barcode data in the newly generated file matches the barcode data printed on the pieces is vital.

Another common cause is use of an incorrect Mailer Identification (MID), either in the barcode on the mail piece, or in the Piece Detail Record (PDR) or Piece Barcode Record (PBC) of the Mail.dat file. To prevent this, it is important to implement quality assurance (QA) steps in your workflow to provide a check point to ensure that this data matches between the physical mail piece and the eDoc.

Yet another common culprit is that many mailers have small jobs, usually single-piece rate First-Class Mail, that have been printed with IMbs and metered but would not be presorted in any way. By definition, these pieces will be undocumented since no eDoc was provided. The resolution is to presort these small mailings. Domestic Mail Manual (DMM) 604.5.1.2 allows for presort of these small jobs that are less than the minimum for a bulk mailing. The Mail.dat files for these small jobs may be merged using post-presort software, so that there is a single submission to PostalOne! rather than numerous small submissions.

Unauthorized use of MIDs by another mail service provider or mail owner can also cause issues. Likewise, removing physical pieces from the mailing due to production issues, such as spoilage, can also cause issues. If those pieces are removed from the eDoc, but inadvertently get left in the physical mailing, the USPS won’t be able to match up the scanned barcode. Again, solid QA procedures to validate MIDs and to ensure physical removal of spoiled or pulled pieces helps prevent undocumented piece issues.

MLOCR environments can have their own issues that can lead to undocumented pieces: double feeds of pre-barcoded mail, one pass mail, improperly fed rejects, and Move Update pieces culled from the mailing are some common examples. Here, too, QA procedures can help to minimize these occurrences.

There can also be USPS-caused issues that create the “illusion” of undocumented pieces, when in fact they can be documented. Examples of this are “loop” mail that loops through automated processes multiple times, or technical/maintenance issues with MPE that cause mis-reads.

There are numerous causes for undocumented pieces, so it is a good idea to start identifying why you are seeing undocumented pieces on your Mailer Scorecard and then develop plans to eliminate those issues and to be able to provide the USPS with the information required to successfully challenge an incorrect assessment. The best way to identify undocumented pieces on your mailer’s scorecard is to review your scorecard every day. It is much easier to discover a problem the day after it happened then a week or a month later (even if it is tedious to see the small differences in the scorecards each day). It is also important to have a process to obtain the undocumented piece data from PostalOne! and analyze the data to determine the source of the errors.


The USPS provides information regarding your undocumented pieces on your Mailer Scorecard, available on the Business Customer Gateway. The USPS Guide to Mailer Scorecard includes instructions for drilling down into the error reports to locate the details of undocumented piece errors. Some software and other mailing services vendors have solutions to help you with reducing your undocumented pieces or to help with the research and documentation for contesting the assessments. Now is the time to develop an understanding of the issues you may be facing and work with your vendors to implement a cost-effective solution.

Jeff Peoples is founder, president, and CEO at Window Book. With over 30 years of innovative postal solutions that make using the Postal Service easier and more profitable for mailers and shippers, he has done presentations at industry events, GraphExpo, MAILCOM, the National Postal Forum, Postal Customer Council meetings, Harvard Business Expert Forum, and other industry and direct marketing events.

This article originally appeared in the July/August, 2020 issue of Mailing Systems Technology.