A common carrier is an organization that transports a product or service using its facilities, or those of other carriers.

Traditionally common carrier means a business that transports people or physical goods. In the 20th century, the term came to refer also to utilities (those transporting some service such as communications or public utilities).

A property common carrier is an organization (often a commercial or private business but sometimes a government agency) that provides transportation of persons or goods, often over a definite route according to a regular schedule, making its services available to all who choose to employ them. Airlines, railroads, bus lines , cruise ships and trucking companies are examples of property common carriers.

Post offices would also be considered common carriers but as universally they are operated by governments they are often treated differently than commercial organizations, such as given special privileges.

Common carriers generally exist under a different regulatory regime than specialised carriers, are subject to different laws, and sometimes to different treatment in other ways (e.g. taxation). For example, common carriers generally explicitly have no legal liability for the contents of freight shipped through them unless the customer has purchased excess insurance for that purpose.

A public utility is an organization that holds itself out to the public for hire to provide utility services, such as communication by radio like cellular telephone and satellite television; telecommunication by wire such as telephone, cable tv and the Internet; transmission by physical connection of supplies such as electricity, natural gas, water and sewer services, etc.

With the deregulation of public utilities it may also be used in relation to a common carrier company that provides the final transmission link to consumers' homes or businesses, but consumers can buy their gas or electricity from any of a number of supplier companies, all of whom feed power into the common transmission line (see electricity retailing).