Order printing online: live pricing, a proof before anything prints, and free design in Plavidian Studio™, no account needed
Plavidian760-666-3130Print and mail production in Vista, California.

Postal Encyclopedia

Letter

Letter-size mail

Preparation & ProductionUpdated 2026-07-24

A machinable letter generally falls between 3.5 x 5 inches and 6.125 x 11.5 inches and within thickness/weight limits.

Definition reviewed 2026-07-24. This is a plain-English Plavidian reference; for USPS terms, the Domestic Mail Manual is the authority. For your own job, the final mail class, postage, and preparation are confirmed after list processing and production review.

Related terms in Preparation & Production

Need this applied to a real job?

Ask Plavidian Expert for an answer based on the USPS Domestic Mail Manual, or send us the job and we'll confirm the preparation before you print.

Ask Plavidian Expert Get a Custom Quote