If you are designing a mail piece or envelopes, be sure to check with Mail Services before printing. Call us at extension 3-6000. Any mail piece smaller than this will not be accepted by the U.S. Postal Service, under any circumstances .
Size also affects cost.
The Postal Service charges an 11 cent surcharge on pieces that weigh an ounce or less, but are oversized. Any card larger than this is charged as a letter. The minimum size is the same as it is for letters. The US Postal Service has restrictions on where printing may appear on envelopes, in order to fit in with their automation equipment. The Barcode clear zone is the area in which the barcode is printed.