If you process Mail.dat® files through PostalOne!®, we can help!

Did you know?

For 30 years, Window Book has been improving the operational efficiency of North America’s mailers. Today, over 50% of USPS mail is processed by Window Book clients!

Call 800.524.0380 or select an option above for more details on how we can help your business thrive!

Here are just a few of the ways Window Book can improve the workflow in your mailing operation:

Automate and submit multiple Mail.dat files to PostalOne!, simultaneously.

Receive automated delivery of PostalOne! UPD and finalized (FIN) statements, confirmation pages, XML files, etc.

Edit Mail.dat files using our DAT-MAIL™ Editor and stop wasting time re-running files through Presort.

Use Quick-Fix™ to correct Mail.dat validation errors in real time.

Notify staff of PostalOne! upload errors/successes automatically via email or text.

Integrate your postage data with other internal systems (accounting, customer service, etc.) for a seamless workflow.

Create a fully lights-out environment where files are processed, uploaded and postage statements are returned with no human interaction.

Monthly Newsletter

Thinking Outside The Mailbox

Read and learn about Window Book, Inc and the Mailing/Shipping industry…


High Performance address correction and standardization software for 64-bit Windows, batch processing and single address lookup via DLL provided for popular development environments.

Address standardization and CASS compliant address corrections


YourScore™ YourScore™

The Quickest and Easiest Way to Monitor and Manage your Mailer Scorecard

Click on the FREE Trial button below and enter Promo Code FREE30DAYS to test drive YourScore for 30 days.

FREE Trial