| Discovery DJ Pipeline LLC | Owner/operator | | | |
| Discovery Gas Transmission LLC | Owner/operator | Tulsa, OK | 12 | 1 |
| Discovery Producer | Owner/operator | | 1 | |
| Discovery Producer Services LLC | Owner/operator | Tulsa, OK | 4 | 3 |
| Distrigas of Massachusetts LLC | Owner/operator | Everett, MA | 3 | |
| Diversified Gas & Oil Corporation | Owner/operator | | | |
| Diversified Midstream LLC | Owner/operator | Birmingham, AL | 1 | 58 |
| Diversified Production | Owner/operator | Birmingham, AL | 4 | 4 |
| Divide Creek Gathering System, LLC | Owner/operator | Houston, TX | | 1 |
| Dixie Pipeline | Owner/operator | Houston, TX | | 1 |
| Dod Defense Energy Support Center | Owner/operator | Fort Belvoir, VA | | 1 |
| Doe Run Gas Transmission Company | Owner/operator | | | |
| Dogwood Energy, LLC | Owner/operator | Pleasant Hill, MO | | 1 |
| Dome Petroleum LLC | Owner/operator | Calgary, Alberta, TX | | 1 |
| Dominion Carolina Gas Transmission, LLC | Owner/operator | | 3 | |
| Dominion Cove Point LNG PL Co | Owner/operator | | 5 | |
| Dominion Cove Point LNG, LP | Owner/operator | | 12 | |
| Dominion East Ohio | Owner/operator | | 6 | |
| Dominion East Ohio Gas Company | Owner/operator | | 10 | |
| Dominion Energy | Owner/operator | | 1 | 2 |
| Dominion Energy Carolina Gas | Owner/operator | | 1 | |
| Dominion Energy Carolina Gas Transmission, LLC | Owner/operator | | 1 | |
| Dominion Energy Cove Point LNG, LP | Owner/operator | | 1 | |
| Dominion Energy Ohio | Owner/operator | | 2 | 3 |
| Dominion Energy Overthrust Pipeline | Owner/operator | | 2 | |
| Dominion Energy Questar Field Services | Owner/operator | | | 1 |
| Dominion Energy Questar Pipeline, LLC | Owner/operator | | 2 | 5 |
| Dominion Energy South Carolina, Inc. | Owner/operator | Cayce, SC | | 1 |
| Dominion Energy Transmission Co | Owner/operator | | 6 | 50 |
| Dominion Energy Utah/wyoming/idaho | Owner/operator | | | |
| Dominion Exploration & Production | Owner/operator | | | |
| Dominion Field Services Inc | Owner/operator | | | |
| Dominion Gathering and Processing, Inc. | Owner/operator | | | 4 |
| Dominion Hope | Owner/operator | | | |
| Dominion Hope Gas Inc | Owner/operator | | 2 | |
| Dominion Peoples | Owner/operator | | | |
| Dominion South Pipeline Co., LP | Owner/operator | | 1 | |
| Dominion Transmision, Inc. | Owner/operator | | | |
| Dominion Transmission, Inc. | Owner/operator | | 35 | |
| Dominion Virginia Power | Owner/operator | Norfolk, VA | | 1 |
| Domtar Paper Company | Owner/operator | Kingsport, TN | | 1 |
| Dos Caminos, LLC | Owner/operator | San Antonio, TX | | 3 |
| Dos Cominos LLC | Owner/operator | | 1 | |
| Double D Pipeline Services, Inc. | Contractor | | | |
| Double E Pipeline, LLC | Owner/operator | | 3 | |
| Double Eagle Pipeline LLC | Owner/operator | Houston, TX | | 4 |
| Double H | Owner/operator | Houston, TX | | 1 |
| Double M Construction Co., Inc. | Contractor | | | |
| Double M Petroproperties, Inc. | Owner/operator | | | 2 |
| Double Play Oil & Gas, Inc | Owner/operator | Portland, TX | | 1 |