| Parent company | Operating company | Operating states |
| AES Corporation | AES Indiana, formerly Indianapolis Power & Light | IN |
| AES Corporation | Dayton Power and Light | OH |
| Allete | Minnesota Power | MN |
| Allete | Superior Water, Light and Power | WI |
| Alliant Energy | Interstate Power and Light | IA |
| Alliant Energy | Wisconsin Power and Light | WI |
| Ameren | Ameren Illinois | IL |
| Ameren | Ameren Missouri | MO |
| American Electric Power | AEP Ohio | OH, WV |
| American Electric Power | AEP Texas | TX |
| American Electric Power | Appalachian Power | TN, VA, WV |
| American Electric Power | Indiana Michigan Power | IN, MI |
| American Electric Power | Kentucky Power | KY |
| American Electric Power | Public Service Company of Oklahoma | OK |
| American Electric Power | Southwestern Electric Power | TX |
| American Transmission Company | American Transmission Company | WI, MI |
| Avista Corporation | Avista Utilities | ID, WA |
| Black Hills Corporation | Black Hills Energy | CO, SD, IA, KS, NE, WY, MT, AR |
| CenterPoint Energy | CenterPoint Energy | TX |
| Fortis Inc. | Central Hudson Gas & Electric | NY |
| Cleco Holdings | Cleco | LA |
| Consolidated Edison | Consolidated Edison | NY |
| Consolidated Edison | Orange and Rockland Utilities | NY, NJ, PA |
| CMS Energy | Consumers Energy | MI |
| Dominion Energy | Dominion Virginia Power | VA |
| Dominion Energy | Dominion North Carolina Power | NC |
| DQE | Duquesne Light | PA |
| DTE Energy Electric Company | Detroit Edison | MI |
| Duke Energy | Duke Energy Carolinas | NC, SC |
| Duke Energy | Duke Energy Progress | NC, SC |
| Duke Energy | Duke Energy Indiana | IN |
| Duke Energy | Duke Energy Ohio | OH |
| Duke Energy | Duke Energy Kentucky | KY |
| Duke Energy | Duke Energy Florida | FL |
| Edison International | Southern California Edison | CA |
| Emera | Bangor Hydro Electric | ME |
| Emera | Maine Public Service | ME |
| Énergir | Central Vermont Public Service | VT |
| Énergir | Green Mountain Power | VT |
| Entergy | Entergy Arkansas | AR |
| Entergy | Entergy Louisiana | LA |
| Entergy | Entergy Gulf States | LA |
| Entergy | Entergy Mississippi | MS |
| Entergy | Entergy New Orleans | LA |
| Entergy | Entergy Texas | TX |
| Evergy | Evergy | MO, KS |
| Eversource Energy | Connecticut Light & Power | CT |
| Eversource Energy | Public Service New Hampshire | NH |
| Eversource Energy | Western Massachusetts Electric | MA |
| Exelon | Commonwealth Edison | IL |
| Exelon | Philadelphia Electric | PA |
| Exelon | Baltimore Gas & Electric | MD |
| Exelon | Potomac Electric Power | DC, MD |
| Exelon | Delmarva Power | DE, MD |
| Exelon | Atlantic City Electric | NJ |
| FirstEnergy | Ohio Edison | OH |
| FirstEnergy | Cleveland Electric Illuminating | OH |
| FirstEnergy | Toledo Edison | OH |
| FirstEnergy | Pennsylvania Power | PA |
| FirstEnergy | Penelec | PA |
| FirstEnergy | Met-Ed | PA |
| FirstEnergy | Jersey Central P&L | NJ |
| FirstEnergy | Allegheny Energy | PA |
| FirstEnergy | Monongahela Power | WV |
| FirstEnergy | Potomac Edison | MD, WV, VA |
| FirstEnergy | West Penn | PA |
| Hawaiian Electric Industries | Hawaii Electric Company | HI |
| Hawaiian Electric Industries | Hawaii Electric Light Company | HI |
| Hawaiian Electric Industries | Maui Electric Company | HI |
| Iberdrola | Rochester Gas & Electric | NY |
| Iberdrola | New York State Electric & Gas | NY |
| Iberdrola | Central Maine Power | ME |
| Integrys Energy Group | Wisconsin Public Service Corporation | WI |
| Integrys Energy Group | Upper Peninsula Power Company | MI |
| ITC Holdings | ITC Transmission | MI |
| ITC Holdings | Michigan Electric Transmission Company | MI |
| ITC Holdings | ITC Midwest | IA, MN, IL, MO |
| ITC Holdings | ITC Great Plains | OK, KS |
| MDU Resources | Montana-Dakota Utilities | MT, ND, SD, WY |
| MGE Energy | Madison Gas and Electric | WI |
| Berkshire Hathaway Energy | MidAmerican Energy Company | IA, IL, SD, NE |
| Berkshire Hathaway Energy | Pacificorp--Pacific Power | OR, CA, WA |
| Berkshire Hathaway Energy | Pacificorp--Rocky Mountain Power | UT, WY, ID |
| Berkshire Hathaway Energy | NV Energy | NV, CA |
| National Grid plc | New England Power | MA, NH, VT, CT, ME |
| National Grid plc | Massachusetts Electric | MA |
| National Grid plc | Nantucket Electric | MA |
| National Grid plc | Granite State Electric | NH |
| National Grid plc | Niagara Mohawk Power | NY |
| National Grid plc | Long Island Lighting | NY |
| NextEra Energy | Florida Power & Light | FL |
| NextEra Energy | Gulf Power | FL |
| NiSource | Northern Indiana Public Service Company | IN |
| NorthWestern Corporation | NorthWestern Energy | SD, MT, NE |
| NRG Energy | Reliant Energy | TX |
| NSTAR | Boston Edison | MA |
| NSTAR | Cambridge Electric Light | MA |
| NSTAR | Commonwealth Electric | MA |
| OGE Energy Corporation | Oklahoma Gas & Electric | OK, AR |
| Otter Tail Corporation | Otter Tail Power | ND, MN, SD |
| PG&E Corporation | Pacific Gas & Electric Company | CA |
| Pinnacle West Capital | Arizona Public Service | AZ |
| PNM Resources | Public Service Company of New Mexico | NM |
| PNM Resources | Texas-New Mexico Power | TX |
| Portland General Electric | Portland General Electric | OR |
| PPL Corporation | PPL Electric Utilities | PA |
| Louisville Gas & Electric | KY | - |
| Kentucky Utilities | KY | - |
| Rhode Island Energy | RI | - |
| Public Service Enterprise Group | Public Service Electric & Gas | NJ |
| Puget Energy | Puget Sound Energy | WA |
| SCANA | South Carolina Electric & Gas Company | SC |
| Sempra Energy | San Diego Gas & Electric | CA |
| Southern Company | Alabama Power | AL |
| Southern Company | Georgia Power | GA |
| Southern Company | Mississippi Power | MS |
| TECO Energy | Tampa Electric | FL |
| UGI Corporation | United Electric Company | PA |
| UIL Holdings Corporation | The United Illuminating Company | CT |
| UniSource Energy | Tucson Electric Power | AZ |
| UniSource Energy | UNS Electric | AZ |
| Unitil | Unitil Energy | MA, NH |
| Unitil | Fitchburg Gas & Electric | MA |
| Vectren | Southern Indiana Gas and Electric | IN |
| Wisconsin Energy Corporation | We Energies | WI |
| Xcel Energy | Northern States Power Company | MN, ND, SD, WI |
| Xcel Energy | Public Service Colorado | CO |
| Xcel Energy | Southwestern Public Service | NM, TX |