US Postal Service mulls 5-day-a-week delivery - Reuters The financially squeezed U.S. Postal Service is asking reluctant lawmakers to lift a 26-year-old requirement that it deliver mail six days a week. Postmaster General John Potter made the surprise request at a U.S. congressional hearing on Wednesday, saying it may have to cut deliveries to five days a week. The proposal may have little impact on rival U.S. package delivery giants United Parcel Service Inc and FedEx Corp. Both companies carry express mail for the U.S. Postal Service under contract.