The U.S. Postal Service is raising shipping and stamp prices. Bulk mailing companies say the increase is too high.

As a new Postmaster General with ties to FedEx assumes control of the agency, postal workers and their customers are bracing for either scenario, especially as corporate America weighs in.

This round of changes, beginning July 1, includes expanding service standard bands for First-Class Mail and USPS Ground Advantage, following earlier dispatch times from regional processing and ...