New 05-2 Mail.dat file specification

We are currently working on incorporating changes for the upcoming implementation of new Mail.dat specification requirements, Mail.dat 05-2.

Details from the IDEAlliance website:

  • Mail.dat 05-2 will be implemented with the following transition window:

    • Mail preparer May Start (Users Must be Able To Catch) using Mail.dat 05-2 on April 10, 2006
    • Mail preparer Must Start (Must Send) using Mail.dat 05-2 on May 8, 2006.

  • PostalOne! will have a release accommodating all Mail.dat 05-2 changes on April 9, 2006.
  • USPS Mailing Standards will write the final rule for the “250 pound pallet requirement” with a Must Comply date of May 11, 2006.
  • All other emerging USPS prep changes will have a Must Comply date later than May 8, 2006.

Window Book clients, prospects, and list houses – please send us your sample 05-2 Mail.dat files for testing! Once coding is completed for Validation purposes, we will use your sample files for testing, and send you a free Validation report on each file submitted. You can send zipped up file sets directly to me at