Postage is based on the price that applies to the weight (postage) increment of each addressed piece. All prices and fees can be found in Notice 123—Price List.
[1-17-16] First-Class Package Service prices start at 1 ounce and must weigh less than 16 ounces. Any fraction of an ounce is considered a whole ounce.
[1-17-16] Commercial prices are available when paid by one of the following methods:
a. Registered end-users of USPS-approved PC Postage products when using a qualifying shipping label, managed by the PC Postage system.
d. Permit holders using Merchandise Return Service (MRS) for First-Class Package Service mailpieces when all MRS requirements are met (505.3.0).
[1-17-16] A surcharge applies for parcels that are irregularly shaped, such as rolls, tubes, and triangles.
[1-17-16] In addition to restricted material described in 601.8.0, parcels mailed at First-Class Package Service prices may not contain documents or personal correspondence, except that such parcels may contain invoices, receipts, incidental advertising, and other documents that relate in all substantial respects to merchandise contained in the parcels.
[1-17-16] See 233.2.0 for a detailed description of matter required to be mailed as First-Class Mail or Priority Mail. The following types of contents must be mailed as First-Class Mail or -Priority Mail:
[1-17-16] First-Class Package Service parcels receive expeditious handling and transportation.
3.2.1 Inspection of Contents
[1-17-16] Articles mailed at First-Class Package Service prices are not sealed against postal inspection. Regardless of physical closure, the mailing of articles at First-Class Package Service prices constitutes consent by the mailer to postal inspection of the contents.
The postage price of First-Class Package Service parcels includes forwarding service to a new address for up to 12 months and return of undeliverable parcels to the sender.
Extra services are available for First-Class Package Service parcels under 503 and for Hold for Pickup service under 508.7.0.
[1-17-16] All First-Class Package Service parcels must:
3.4 IMpb Standards
All First-Class Package Service parcels must bear an Intelligent Mail package barcode (IMpb) prepared under 708.5.0. Mailpieces not meeting the requirements for use of unique Intelligent Mail package barcodes or extra services barcodes as outlined in Publication 199 will be assessed an IMpb noncompliance fee. For details see the RIBBS website at https://ribbs.usps.gov.