Topic summary
U.S. mail
Extracted from the Wikipedia article United States Postal Service.
Monopoly and competition
Due to the postal monopoly, neither FedEx nor United Parcel Service (UPS) are allowed to deliver non-urgent letters, and may not directly ship to U.S. Mail boxes at residential and commercial destinations. However, both companies have transit agreements with the USPS in which an item can be dropped off with either FedEx or UPS who will then provide shipment up to the destination post office serving the intended recipient where it will be transferred for delivery to the U.S. Mail destination, including Post Office Box destinations. These services also deliver packages which are larger and heavier than USPS will accept.