How should I design the mailing panel of my mailpiece?
The mailing panel needs to be formatted to U.S. Postal Service specifications. A good rule of thumb (in addition to the Aspect Ratio listed above) is to leave at least 3.5″ of white space on the right-hand side of the mail panel and 5/8″ along the bottom. This space is required to accommodate the indicia, the mailing address, and any barcodes that will be applied. Please leave this area white (though a light color is generally acceptable). The U.S. Postal Service website is also a valuable resource for information about how to design mailpieces.
