Postal Standards - The Graphic Design: Reference and Specification - page 117

Chapter 11: Postal Standards
g e n e r a l u s p s m a i l c l a s s i f i c at i o n s a n d r e q u i r e m e n t s
The United States Postal Service (USPS) rates are based on mail that is automation com-
patible.
Machinable: mail pieces that fall within the min/max size specs, rectangular in shape, con-
structed of paper and sealed per USPS specifications. Charged at a lower rate.
Non-machinable: mail pieces that include rolls, tubes, and anything irregularly shaped,
which do not comply with the size and aspect ration requirement and thus cannot be sorted
on automated equipment. Charged at a higher rate.
Always show a folded mock-up to your post office agent to ensure it meets the USPS guide-
lines prior to finalizing your design. The standards and requirements listed are current at
the time of publication. Visit www.usps.com for standards and requirements updates.
Postcard
Rectangular card stock mail piece not
contained within an envelope.
Large envelope or flat
Flat, rectangular mail piece.
Letter
Small, rectangular mail piece.