It's Unmailable?!

After the job is printed, that’s the worst message you can hear. While you may be following the client’s design, if he wants a postcard in the shape of a triangle, it won’t fly and it will be your fault since he expected you to know that it wouldn’t. Almost equally bad is the news that the piece will have to go at First Class rates because its design disqualifies it for Standard Class. For example, if the piece is square rather than rectangular.

The USPS website contains an amazing amount of information on these rules and also the location of the Mailpiece Design Analysts who will accept PDFs of the project and give an official ruling as to whether they can enter the mail stream and if they will qualify for discounted rates.