| Comeser Parma | Comeser S.r.l. | Fidenza | Italy | 0 | 0 |
| Cometa Internet | Maila Networks | Porto Alegre | Brazil | 1 | 0 |
| Comlink Telecom | Comlink Ltd | St. Petersburg | Russia | 0 | 0 |
| Communications House | Uganda Internet Exchange Point | Kampala | Uganda | 4 | 1 |
| COMNET Datacenter Istanbul | Comnet Bilgi İletişim Teknolojileri A.Ş. | Istanbul | Turkey | 31 | 3 |
| Comnet Tashkent | IPLUS LLC | Tashkent | Uzbekistan | 1 | 1 |
| Compania de Informatica Aplicata | Compania de Informatica Aplicata | Cluj Napoca | Romania | 2 | 0 |
| Completel Val de Reuil | Completel SAS | Paris | France | 2 | 0 |
| Computer Concepts Limited (CCL) Christchurch DC | Computer Concepts Limited (CCL) | Christchurch | New Zealand | 15 | 1 |
| ComSpace III | ARTERIA Networks Corporation (Vectant) | Tokyo | Japan | 0 | 0 |
| comtrance Duesseldorf | comtrance GmbH | Düsseldorf | Germany | 7 | 0 |
| Comway Sibiu | Comway Telecommunication SRL | Sibiu | Romania | 0 | 0 |
| Conapto Stockholm Nord (Sollentuna) | Conapto AB | Sollentuna | Sweden | 1 | 4 |
| Conapto Stockholm Syd (Sätra) | Conapto AB | Skärholmen | Sweden | 0 | 4 |
| Congo Telecom Carrier Facility PNR1 | Congo Telecom | Pointe-Noire | Congo - Brazzaville | 2 | 0 |
| Connect Cedar Valley | Connect Des Moines, LLC | Cedar Falls | United States | 0 | 0 |
| Connect Des Moines | Connect Des Moines, LLC | Des Moines | United States | 10 | 0 |
| Connect plus s.r.o. | Connect plus s.r.o. | Prague | Czechia | 0 | 0 |
| Connected Krakow | Connected sp. z o.o. | Krakow | Poland | 7 | 0 |
| conova - Datacenter 4/5 | conova communications GmbH | Salzburg | Austria | 5 | 1 |
| conova - Datacenter 6/7 | conova communications GmbH | Hallein | Austria | 1 | 1 |
| Consolidated - 266 Main St. | Consolidated Communications, Inc. | Burlington | United States | 1 | 0 |
| Consolidated - 45 Forest Ave. | Consolidated Communications, Inc. | Portland | United States | 1 | 0 |
| Consolidated - 770 Elm St. | Consolidated Communications, Inc. | Manchester | United States | 0 | 0 |
| Consolidated - 811 Louisiana | Consolidated Communications, Inc. | Houston | United States | 4 | 0 |
| CONSORCIO DE TELECOMUNICACIONES AVANZADA S.A. | CONSORCIO DE TELECOMUNICACIONES AVANZADA S.A. | Alcantarilla | Spain | 2 | 0 |
| CONSTEL TECNOLOGIA | Constel Tecnologia LTDA | Cascavel | Brazil | 2 | 0 |
| Continental Plaza | Bresco Broadband | Columbus | United States | 1 | 1 |
| Convergenze Innovation Center | Convergenze S.p.A.SB | Capaccio-Paestum | Italy | 4 | 0 |
| Convex iDC RPO | Convex Internet Solutions | Ribeirão Preto | Brazil | 0 | 0 |
| COOLNET | Automation & Business, s.r.o., COOL NET | Piestany | Slovakia | 0 | 0 |
| COPT DC-6 | COPT DATA MANAGEMENT, LLC | Manassas | United States | 8 | 0 |
| Core-Backbone NBG1 | Core-Backbone GmbH | Nuremberg | Germany | 7 | 1 |
| Core-Backbone NBG2 | Core-Backbone GmbH | Nuremberg | Germany | 9 | 1 |
| Core-Backbone NBG3 | Core-Backbone GmbH | Nuremberg | Germany | 7 | 1 |
| Corepacket PDX-1 | FIBERFI | Portland | United States | 3 | 1 |
| CoreSite - Atlanta (AT1) | CoreSite | Atlanta | United States | 69 | 4 |
| CoreSite - Atlanta (AT2) | CoreSite | Marietta | United States | 6 | 2 |
| CoreSite - Boston (BO1) | CoreSite | Somerville | United States | 40 | 2 |
| CoreSite - Chicago (CH1) | CoreSite | Chicago | United States | 73 | 6 |
| CoreSite - Chicago (CH2) | CoreSite | Chicago | United States | 15 | 2 |
| CoreSite - Denver (DE1) | CoreSite | Denver | United States | 150 | 3 |
| CoreSite - Denver (DE2) | CoreSite | Denver | United States | 14 | 1 |
| CoreSite - Los Angeles (LA1) One Wilshire | CoreSite | Los Angeles | United States | 335 | 5 |
| CoreSite - Los Angeles (LA2) | CoreSite | Los Angeles | United States | 196 | 3 |
| CoreSite - Los Angeles (LA3) | CoreSite | Los Angeles | United States | 18 | 2 |
| CoreSite - Miami (MI1) | CoreSite | Miami | United States | 21 | 2 |
| CoreSite - Miami (MI2) | CoreSite | Doral | United States | 4 | 2 |
| Coresite - Milpitas (SV2) | CoreSite | Milpitas | United States | 6 | 2 |
| CoreSite - New York (NY1) | CoreSite | New York | United States | 35 | 4 |