| .clothing | Generic | Binky Moon, LLC | — | — |
| .cloud | Generic | ARUBA PEC S.p.A. | — | — |
| .club | Generic | Registry Services, LLC | — | — |
| .clubmed | Generic | Club Méditerranée S.A. | — | — |
| .cm | Country Code | Agence Nationale des Technologies de l'Information et de la Communication (ANTIC) | 🇨🇲Cameroon | — |
| .cn | Country Code | China Internet Network Information Center (CNNIC) | 🇨🇳China | — |
| .co | Country Code | Ministry of Information and Communications Technologies (MinTIC) | 🇨🇴Colombia | — |
| .coach | Generic | Binky Moon, LLC | — | — |
| .codes | Generic | Binky Moon, LLC | — | — |
| .coffee | Generic | Binky Moon, LLC | — | — |
| .college | Generic | XYZ.COM LLC | — | — |
| .cologne | Generic | dotKoeln GmbH | — | — |
| .com | Generic | VeriSign Global Registry Services | — | — |
| .commbank | Generic | COMMONWEALTH BANK OF AUSTRALIA | — | — |
| .community | Generic | Binky Moon, LLC | — | — |
| .company | Generic | Binky Moon, LLC | — | — |
| .compare | Generic | Registry Services, LLC | — | — |
| .computer | Generic | Binky Moon, LLC | — | — |
| .comsec | Generic | VeriSign, Inc. | — | — |
| .condos | Generic | Binky Moon, LLC | — | — |
| .construction | Generic | Binky Moon, LLC | — | — |
| .consulting | Generic | Dog Beach, LLC | — | — |
| .contact | Generic | Dog Beach, LLC | — | — |
| .contractors | Generic | Binky Moon, LLC | — | — |
| .cooking | Generic | Registry Services, LLC | — | — |
| .cool | Generic | Binky Moon, LLC | — | — |
| .coop | Sponsored | DotCooperation LLC | — | — |
| .corsica | Generic | Collectivité de Corse | — | — |
| .country | Generic | Internet Naming Co. | — | — |
| .coupon | Generic | Amazon Registry Services, Inc. | — | — |
| .coupons | Generic | Binky Moon, LLC | — | — |
| .courses | Generic | Registry Services, LLC | — | — |
| .cpa | Generic | American Institute of Certified Public Accountants | — | — |
| .cr | Country Code | National Academy of Sciences (Academia Nacional de Ciencias) | 🇨🇷Costa Rica | — |
| .credit | Generic | Binky Moon, LLC | — | — |
| .creditcard | Generic | Binky Moon, LLC | — | — |
| .creditunion | Generic | DotCooperation, LLC | — | — |
| .cricket | Generic | dot Cricket Limited | — | — |
| .crown | Generic | Crown Equipment Corporation | — | — |
| .crs | Generic | Federated Co-operatives Limited | — | — |
| .cruise | Generic | Viking River Cruises (Bermuda) Ltd. | — | — |
| .cruises | Generic | Binky Moon, LLC | — | — |
| .cu | Country Code | CENIAInternet | 🇨🇺Cuba | — |
| .cuisinella | Generic | SCHMIDT GROUPE S.A.S. | — | — |
| .cv | Country Code | Agência Reguladora Multissectorial da Economia (ARME) | 🇨🇻Cabo Verde | — |
| .cw | Country Code | University of Curacao | 🇨🇼Curacao | — |
| .cx | Country Code | Christmas Island Domain Administration Limited | 🇨🇽Christmas Island | — |
| .cy | Country Code | University of Cyprus | 🇨🇾Cyprus | — |
| .cymru | Generic | Nominet UK | — | — |
| .cyou | Generic | Shortdot SA | — | — |