Mailing Pros, Inc. is your advocate in the mailing process. We may not be able to tell you if your latest greatest mailing idea will work, however, from our vast experience, IF WE THINK THAT IT WILL NOT WORK WE WILL TELL YOU!

These PDF documents are intended as a “guide” only. To make sure that your documents follow the proper postal guidelines please call us or consult with your local post office.

If you have any questions about mail piece design or standardization please call Mailing Pros Inc. at: 714-892-7251

You may think that your mailpiece is a “postcard,” because it is a single sheet of paper/card stock. But to qualify for mailing at the First-Class Mail postcard price, it must follow guidelines specific to postcards.
The Postal Service uses the word “flats” to refer to large envelopes, newsletters, and magazines. The words large envelopes and flats are used interchangeably.
Letters can be more than a standard No. 10 envelope. This category includes letter-size cards and booklets.
Booklets are a particular kind of letter that has multiple pages and a bound edge or spine.
When designing your envelope (No. 9 or No. 10) follow these envelope templates to ensure problem free mailing.
A folded self-mailer is formed of at least two panels created when a single or multiple unbound sheets of paper are folded together and sealed to form a letter-size mailpiece.

Helpful information on:
• Addressing
• Aspect ratio
• Formatting and more