A carrier is a term used to refer to an operator that provides transportation services. A carrier can be an individual or a company that operates both passenger and freight transport, including both public and private contractual transport.

A carrier can operate in various modes of transport, such as: road (on land roads), rail (on railways, tramways, trolleybus, or cable car systems), air, or water transport.

In logistics, the term "freight carrier" is used to describe an operator responsible for the transportation of goods. The freight carrier may hire services from a transport company, which will then physically deliver the goods.