Courier services encompass the delivery of messages, packages, and mail, and are distinguished from ordinary mail services by features such as speed, security, tracking, signature, specialization and individualization of express services, and swift delivery times. In the U.S., the courier service industry is dominated by FedEx, DHL, United Parcel Service and USA Couriers. As a premium service, couriers are usually more expensive than standard mail services.
Express services, available in both domestic and international, offer faster mail delivery services. In the U.S., Priority Mail Express is the accelerated domestic mail delivery service operated by the United States Postal Service (USPS). In 2017, the total mail volume for USPS amounted to around 149.5 billion and the company had around 503,000 employees. Some private couriers own their own aircraft for long distance deliveries and run their own delivery networks through firms, such as FedEx Express or DHL Express. In 2016, FedEx Express recorded freight revenue amounting to about four billion U.S. dollars.
Parcel (or package) service providers deliver mail that is too heavy for normal letter post service. United Parcel Service (UPS) is the largest and most commonly used package delivery company in the U.S., according to a Statista survey. In 2016 alone, UPS generated over 60 billion in annual revenue. Ground transportation dominates the market for parcel delivery in the United States.