| Clinton | Gas processing plant | Custer County, OK | ET Gathering & Processing, LLC, Enable Products LLC | In service |
| Clovelly Salt Dome Crude Oil Storage | Underground storage | LA | | |
| Clovis Compressor Station | Compressor station | Canadian County, OK | Oneok Field Services Inc | |
| Clyde Compressor Station | Compressor station | Grant County, OK | Targa Pipeline Midcontinent Westok LLC | |
| Coalgate Plant | Gas processing plant | Coal County, OK | Enable Midstream Partners, LP | In service |
| Coalgate Stonewall Gas Plant | Gas processing plant | Coal County, OK | TPL Arkoma Holdings LLC, Targa Resources | In service |
| Coalville | Underground storage | Summit County, UT | Questar Pipeline | In service |
| Cobb | Underground storage | Blaine County, MT | Northwestern Energy LLC | In service |
| Cobb Compressor Station | Compressor station | Washington County, OK | Gateway Resources USA Inc | |
| Coco A | Underground storage | Kanawha County, WV | Columbia Gas Transmission, LLC | In service |
| Coco B | Underground storage | Kanawha County, WV | Columbia Gas Transmission, LLC | In service |
| Coffey Compressor Station | Compressor station | Coal County, OK | Markwest Oklahoma Gas Company, LLC | |
| Cogar Compressor Station | Compressor station | Caddo County, OK | Enable Oklahoma Intrastate Transmission, LLC | |
| Cold Brook Energy Hampden terminal | Terminal | ME | Cold Brook Energy Inc | |
| Cold Springs 1 | Underground storage | Kalkaska County, MI | ANR Pipeline Company | In service |
| Cold Springs 12 | Underground storage | Kalkaska County, MI | Anr Storage Co | In service |
| Cold Springs 31 | Underground storage | Kalkaska County, MI | Anr Storage Co | In service |
| Colden Storage | Underground storage | Erie County, NY | National Fuel Gas Supply Corporation | In service |
| Coldwater Compressor Station | Compressor station | Texas County, OK | DCP Operating Company, LP | |
| Cole Compressor Station | Compressor station | Mcclain County, OK | DCP Operating Company, LP | |
| Coleman Bullis Compressor Station | Compressor station | Kingfisher County, OK | Bce-Mach III Midstream Holdings LLC | |
| Collins Field | Underground storage | St. Clair County, MI | Semco Energy Gas Company | In service |
| Collins Storage | Underground storage | Erie County, NY | National Fuel Gas Supply Corporation | In service |
| Colonial Terminal Operating Chattanooga | Terminal | TN | Colonial Terminal Operating Co LLC | |
| Colonial Terminals Operating Charlotte | Terminal | NC | Colonial Terminals Operating Co LLC | |
| Colonial Terminals Operating Fredericksburg | Terminal | VA | Colonial Terminals Operating Co LLC | |
| Colonial Terminals Savannah | Terminal | GA | Colonial Terminals Inc | |
| Colony | Underground storage | Anderson County, KS | Southern Star Central Gas Pipeline, Inc. | In service |
| Columbia Gas Trans Corp/forks TWP Fac Easton Cta | Compressor station | Northampton County, PA | Columbia Gas Transmission, LLC | |
| Columbia Gas Trans Corp/gettysburg Comp Sta | Compressor station | Adams County, PA | Columbia Gas Transmission, LLC | |
| Columbia Gas Trans Corp/greencastle | Compressor station | Franklin County, PA | Columbia Gas Transmission, LLC | |
| Columbia Gas Trans Corp/hellertown CT | Compressor station | Northampton County, PA | Columbia Gas Transmission, LLC | |
| Columbia Gas Trans Corp/marietta | Compressor station | Lancaster County, PA | Columbia Gas Transmission, LLC | |
| Columbia Gas Trans Corp/milford Comp Sta | Compressor station | Pike County, PA | Columbia Gas Transmission, LLC | |
| Columbia Gas Trans Corp/renovo Sta | Compressor station | Clinton County, PA | Columbia Gas Transmission, LLC | |
| Columbia Gas Trans Llc/artemas Comp Sta | Compressor station | Bedford County, PA | Columbia Gas Transmission, LLC | |
| Columbia Gas Trans Llc/eagle | Compressor station | Chester County, PA | Columbia Gas Transmission, LLC | |
| Columbia Gas Transmission Chesapeake LNG | LNG peak-shaving or storage | VA | Columbia Gas Transmission, LLC | In service |
| Columbia Gas Transmission, LLC, Adaline Comp. Station | Compressor station | WV | | |
| Columbia Gas Transmission, LLC, Ceredo | Compressor station | WV | | |
| Columbia Gas Transmission, LLC, Charleston | Compressor station | WV | | |
| Columbia Gas Transmission, LLC, Clendenin | Compressor station | WV | | |
| Columbia Gas Transmission, LLC, Clendenin (WV) | Compressor station | WV | | |
| Columbia Gas Transmission, LLC, Cleveland | Compressor station | WV | | |
| Columbia Gas Transmission, LLC, Coco | Compressor station | WV | | |
| Columbia Gas Transmission, LLC, Coco Storage Field A12 Methano | Compressor station | WV | | |
| Columbia Gas Transmission, LLC, Coco Storage Field C | Compressor station | WV | | |
| Columbia Gas Transmission, LLC, Elk River | Compressor station | WV | | |
| Columbia Gas Transmission, LLC, Files Creek | Compressor station | WV | | |
| Columbia Gas Transmission, LLC, Flat Top | Compressor station | WV | | |