Postage for First-Class Package Service parcels must be paid with postage evidencing system postage or permit imprint as specified below. All pieces in a mailing must be paid with the same method unless otherwise authorized by Business Mailer Support (see 608.8.0 for address).
2.0 Postage Payment for Presorted First-Class Package Service Parcels
All First-Class Package Service parcels may bear permit imprint postage under 604.5.0. Parcels entered at commercial plus prices and all mail manifested using the Electronic Verification System (eVS) under 705.2.9 must be paid using a permit imprint. A permit imprint may be used for mailings of nonidentical-weight pieces only if authorized by Business Mailer Support.
Each presorted First-Class Package Service parcel bearing postage evidencing system indicia (IBI Meter or PC Postage permitted for Commercial Base, or PC Postage permitted for Commercial Plus parcels) must bear one of the following:
a. The full numerical value of postage at the First-Class Package Service price for which it qualifies.
b. Full numerical value of postage in an amount not less than the lowest applicable First-Class Package Service parcel price if authorized by Business Mailer Support, plus full numerical value of postage for additional ounces.