Quick Service Guide 230a
Postage is based on the weight of each addressed piece. First-Class Mail letters are charged per ounce or fraction thereof; any fraction of an ounce is considered a whole ounce.
Letters are subject to a nonmachinable surcharge if they meet any of the characteristics in 201.2.1. The nonmachinable characteristics do not apply to pieces mailed at postcard prices.
First-Class Mail is required for personal correspondence, handwritten or typewritten material, and bills or statements of account. First-Class Mail may also be used for most mailable items, including advertisements and lightweight merchandise.
Eligibility Standards (233.4.0)
Mailings of 500 or more addressed pieces, sorted and marked as described below. All pieces must be letter-size and meet one of the nonmachinable criteria in 201.2.0. Pieces mailed at card prices and pieces mailed at letter prices must meet separate 500-piece minimums.
Addresses on all pieces must be updated within 95 days before mailing through a USPS-approved address update method (e.g., ACS, NCOALink, or the appropriate ancillary service endorsement except Forwarding Service Requested, under 507.1.5). For an overview of the Move Update standards, see Quick Service Guide 505b.
When preparing full trays, mailers must fill all possible 2-foot trays first; if there is mail remaining for the presort destination, mailers must use a combination of 1-foot and 2-foot trays that result in the fewest total number of trays for that presort level.