- Caledonian MacBrayne
- Campbell, P&A
- Canadian National Railway & Marine Atlantic
- Canadian Pacific
- Carnival Cruise Line
- Celebrity Cruises
- CGN (Lake Geneva)
- CGT see French Line
- Chandris
- Channel Island Ferries see British
- Chargeurs Reunis
- Chevron/Texaco
- China Navigation Co.
- China Ocean see COSCO
- Clan Line
- Classic International Cruises
- Clipper Cruise Line
- CMA CGM
- Coast Lines
- Cogedar Line
- Colonial, Cia
- Color Line
- COMANAV
- COMARIT see Fred Olsen
- Commodore Cruise Line
- Condor Ferries
- Corsica Ferries
- COSCO (China Ocean)
- Cosens & Co
- Costa
- CoTuNav see Tunisia Ferries
- Cruise & Maritime Voyages
- Crystal Cruises
- CTC
- Cunard Line
- Currie Line
- David MacBrayne see Caledonian
- Delphin Seereisen
- Deutsche OstAfrika Linie
- DFDS
- Direct Cruises
- Disney Cruise Line
- Dolphin Cruise Line
- Dominion Line
- Donaldson Line
- DSB