As the implementation of the Intelligent Mail program in May 2009 draws closer, mailers are looking longer and harder at ways to improve efficiency and reduce costs. Many of them are discovering the benefits of the Mail.dat file specification from the International Digital Enterprise Alliance (IDEAlliance). And for those of you who are considering taking advantage of the Intelligent Mail Full Service option, Mail.dat is one of the few ways allowed by the U.S. Postal Service (USPS) to submit mailings electronically to the USPS PostalOne! system. (Another method is through the Wizard Web Services, which will convert to another IDEAlliance specification, Mail.XML, in the fall of 2009. Mail.XML will be discussed in a follow-up article in the next edition.) The information presented here is a basic Q&A format designed to provide an introduction to the Mail.dat specification, how it can benefit you and your bottom line and maybe dispel a few myths.

What is Mail.dat?
Mail.dat is a file specification that combines information from a number of sub-files to provide a detailed summary and description of a presorted mailing, and as previously discussed, is an integral part of communicating with the USPS PostalOne! system as well as communicating with other organizations in the mailing supply chain. Mail.dat is created during the presort process, either by presorting software processing name-and-address lists or by co-mingling equipment sorting already-assembled mailing pieces. No matter how the sortation is performed, the details that make up the mailing are recorded in the Mail.dat file set for that job.

What are some of the benefits of Mail.dat?
The information in Mail.dat files is extremely useful in mail verification and acceptance, electronic data storage, transportation planning and postal document preparation and reporting. Mail.dat feeds sophisticated reporting to the USPS, letter shop clients and internal departments. The data can be used, for example, to create all of the documentation required by the Postal Service for a mailing, including: postage statements, PS-8125 drop-shipping forms, Qualification Reports, Manifest Mailing System Reports, bag/tray tags as well as pallet placards. Mail.dat facilitates electronic verification and acceptance of the mail as well as the electronic archival and retrieval of past mailing statements and data. Mail.dat also enables more informed decision-making when planning the transportation of your mail.

Other than to submit to PostalOne!, why should I generate Mail.dat files?
As the industry standard, Mail.dat enables individual mailers and the mailing community, at large, to function more efficiently and cost-effectively because when presorters generate Mail.dat files for their mailings, they increase the opportunities for mailers and others in the production chain to take advantage of this valuable information. As this data becomes more widely available, its usage continues to grow in letter shops, printing facilities, logistics companies and among mail owners themselves. As greater efficiencies are achieved through the use of Mail.dat, costs and processing time will be reduced industry-wide.

Does using Mail.dat compromise recipients' confidentiality?
No. While using Mail.dat provides a detailed summary and description of a presorted mailing, the only information not included in a Mail.dat file set are the names and addresses of the intended recipients, so confidentiality is assured.

As a First-Class mailer, can Mail.dat benefit me?
While many recognize that Mail.dat offers significant benefits to mailers of Standard Mail - particularly drop-ship discounts and the ability to communicate electronically with supply chain partners - the Mail.dat file set also presents those mailing First-Class Mail an opportunity to exchange mailing information electronically with the rest of the supply chain and the Postal Service. First-Class mailers (both manifest and commingled-presort mailers) can leverage the same advantages for e-documentation and e-payment that exist for Standard and Periodical mailers.

Will Mail.XML replace Mail.dat as the industry standard?
No. Mail.dat and Mail.XML are different specifications, and Mail.XML will not replace Mail.dat. These specifications currently exist side-by-side and will continue to do so for many years to come. (Mail.dat provides a storage/database model for mailing information while Mail.XML enables two-way communication between the shipper and the consignee.) As mentioned earlier, the next issue of this publication will have a follow-up article devoted to Mail.XML. In the meantime, for more information about Mail.dat and Mail.XML, you can visit the IDEAlliance website at

Wallace Vingelis is Director of Product Management and Postal Affairs for Anchor Software, LLC and currently serves as Co-Chairman of the Mail.dat Specification Committee for IDEAlliance. He can be reached at Anchor Software is a leading provider of data processing software for the direct marketing industry. For more information, visit the Anchor Software website at or call 800-237-1921.