What is Mail.dat?

Mail.dat is not a software system. It's a data formatting standard for communicating information related to the composition of a mailing. This data can be used for:

• logistics planning
• mail assembly and production
• postal payment and acceptance

The Mail.dat format specification, administered by the International Digital Enterprise Alliance (IDEAlliance, formerly the Graphic Communications Association), is rapidly being adopted industry-wide so that it is now possible to send and receive statistical information about mailings without translating the proprietary formatting specifications of various software vendors.

What Does It Look Like?

The Mail.dat standard defines detailed formats for a set of files which, together, are capable of containing virtually "everything there is to know" about a specific mailing, including data at the segment, pallet, sack or tray, and package levels. Individual address-level information is not included.

The current Mail.dat standard (version 02-1) comprises seven mandatory files and twelve optional files. These formats will be modified from time to time by the IDEAlliance.

Key fields in each of the files act as pointers to related fields in the other files so that the complete Mail.dat file-set serves as a fixed-format representation of a relational database.

But not any specific database.

The Mail.dat files are all plain old ASCII fixed-format ("flat") files, making them a perfect medium for communicating complete information describing a complex mailing from one shop to another. These files can easily be imported into any relational database management system or used as-is by in-house software.

For detailed information about the current Mail.dat format specifications, contact the IDEAlliance.

Mail.dat and PostalOne!

The United States Postal Service (USPS) has adopted the Mail.dat format for use in its PostalOne! program. Upon implementation, PostalOne! will allow mailers to submit data electronically – in Mail.dat format – to the USPS for postal acceptance and payment purposes.

Receiving and analyzing this information electronically instead of in the current hard-copy format is expected to speed mail acceptance processing time while reducing costs. The PostalOne! program should also reduce bottlenecks in mail handling facilities by providing more information related to logistical requirements, therefore improving the efficiency of mail delivery nationwide.