C2C is an abbreviation that may refer to:

• c2c, a British train operating company
• C2C (car to car) communication (see vehicular communication systems)
• Cam 2 cam, Internet camera chat, from the instant messaging shorthand "cam-to-cam", usually spelled in lower case "c2c"
• Consumer-to-consumer, the electronically facilitated transactions between consumers through some third party (such as Ebay). Also Customer to customer
• Sea to Sea Cycle Route, the most popular of British long-distance cycle routes
• C2C (cable system), a submarine telecommunications cable system linking east Asia and the USA
• Cradle to Cradle Design, a design philosophy by Michael Braungart and William McDonough
• Copy to China, when a company in China copies the business model of a successful foreign company
• Computer to Computer, an 'Ad Hoc' Ethernet network, usually wireless
• Chip-to-Chip interconnection, a low latency, peer-to-peer communication protocol developed by TI and Arteris, that enables the extension of an serialized local bus to one physical device over a printed circuit board, f.ex. to share the same memory chip between two processors

c2c is a British train operating company owned by National Express Group. It has operated the London, Tilbury & Southend passenger franchise since May 1996 and became the operator of the replacement Essex Thameside franchise from November 2014.