How Quantity Affects Prices
All commercial postage categories have minimum quantities of mail that must be met. Beyond that, your level of sort and the number of pieces in each sortation may qualify your mail for even lower prices.
For stamped or metered single-piece (full price) First-Class Mail: no minimum.
For permit imprint single-piece (full-price) First-Class Mail: 200 pieces OR 50 pounds.
For Presorted and automation First-Class Mail: 500 pieces.
For Standard Mail: 200 pieces OR 50 pounds.
For single-piece (full price) Standard Post, Library Mail, and Media Mail: no minimum.
For destination entry Parcel Select: 50 piece minimum per mailing, 50 pieces or 50 pounds for Parcel Select Nonpresort.
For single-piece Bound Printed Matter: no minimum.
For Presorted and Carrier Route Bound Printed Matter: 300 pieces.
For Commercial Library Mail: 300 pieces.
For Commercial Media Mail: 300 pieces.
Within each class of mail, there also are minimum quantities to qualify for a particular price, depending on how finely your mail is sorted. For example, if 1,000 pieces were all addressed for delivery to one ZIP Code, they would get a better price than 1,000 pieces addressed for delivery nationwide.
Calculate postage for any class of commercial mail or price