| AECO | Transmission Zone | NJ | Atlantic City Electric (Exelon) | MIDATL | PJM-RTO, MAD |
| AECO_ENGLAND | Demand Response | NJ | See Load Management Subzone zip code definitions within the Demand Response section of pjm.com: http://www.pjm.com/markets-and-operations/demand-response.aspx | AECO | N/A |
| AEP | Control Area | IN, KY, MI, OH, TN, VA, WV | AEP: AEP Ohio, Appalachian Power, Indiana Michigan Power & Kentucky Power | WESTERN | PJM-RTO |
| AEP_COLUMBUS | Demand Response | OH | See Load Management Subzone zip code definitions within the Demand Response section of pjm.com: http://www.pjm.com/markets-and-operations/demand-response.aspx | AEP | N/A |
| AEP_MARION | Demand Response | OH | See Load Management Subzone zip code definitions within the Demand Response section of pjm.com: http://www.pjm.com/markets-and-operations/demand-response.aspx | AEP | N/A |
| AMPT | Transmission Zone | OH | American Municipal Power Transmission | WESTERN | PJM-RTO |
| BGE | Transmission Zone | MD | BGE (Exelon) | MIDATL | PJM-RTO, MAD |
| COMED | Control Area | IL | ComEd (Exelon) | WESTERN | PJM-RTO |
| CPP | Control Area | OH | Cleveland Public Power | WESTERN | PJM-RTO |
| DAY | Control Area | OH | Former Dayton Power & Light Company: DP&L | WESTERN | PJM-RTO |
| DEOK | Control Area | KY, OH | Duke Energy: Duke Energy Ohio & Duke Energy Kentucky | WESTERN | PJM-RTO |
| DOM | Control Area | NC, VA | Dominion Virginia Power | SOUTHERN | PJM-RTO, MAD |
| DOM_ASHBURN | Demand Response | VA | See Load Management Subzone zip code definitions within the Demand Response section of pjm.com: http://www.pjm.com/markets-and-operations/demand-response.aspx | DOM | N/A |
| DOM_CHES | Demand Response | VA | See Load Management Subzone zip code definitions within the Demand Response section of pjm.com: http://www.pjm.com/markets-and-operations/demand-response.aspx | DOM | N/A |
| DOM_YORKTOWN | Demand Response | VA | See Load Management Subzone zip code definitions within the Demand Response section of pjm.com: http://www.pjm.com/markets-and-operations/demand-response.aspx | DOM | N/A |
| DPL | Transmission Zone | DE, MD, VA | Delmarva Power (Exelon); including Accomack & Northampton counties in VA | MIDATL | PJM-RTO, MAD |
| DUQ | Control Area | PA | Duquesne Light Company | WESTERN | PJM-RTO |
| EKPC | Control Area | KY | East Kentucky Power Cooperative | WESTERN | PJM-RTO |
| FE-AP | Control Area | MD, PA, VA, WV | Former AP: West Penn Power, Mon Power, Potomac Edison/TrAIL Co VA Transmission Zone & Potomac Edison (FirstEnergy; FE-South) | WESTERN | PJM-RTO |
| FE-AP_EAST | Demand Response | MD, PA, VA, WV | See Load Management Subzone zip code definitions within the Demand Response section of pjm.com: http://www.pjm.com/markets-and-operations/demand-response.aspx | FE-AP | N/A |
| FE-ATSI | Control Area | OH | Former ATSI: Penn Power, Ohio Edison, The Illuminating Company & Toledo Edison (FirstEnergy; FE-West) | WESTERN | PJM-RTO |
| FE-JC | Transmission Zone | NJ | Former GPU: Jersey Central Power & Light (FirstEnergy; FE-East) | MIDATL | PJM-RTO, MAD |
| FE-JC_REDBANK | Demand Response | NJ | See Load Management Subzone zip code definitions within the Demand Response section of pjm.com: http://www.pjm.com/markets-and-operations/demand-response.aspx | FE-JC | N/A |
| FE-ME | Transmission Zone | PA | Former GPU: Met-Ed (FirstEnergy; FE-East) | MIDATL | PJM-RTO, MAD |
| FE-PN | Transmission Zone | PA | Former GPU: Penelec (FirstEnergy; FE-East) | MIDATL | PJM-RTO, MAD |
| MIDATL | Region | DC, DE, MD, NJ, PA, VA | PJM Mid-Atlantic Region/CZ; including Accomack & Northampton counties in VA | PJM-RTO | PJM-RTO, MAD |
| OVEC | Transmission Zone | IN, KY, OH | Ohio Valley Electric Corporation | WESTERN | PJM-RTO |
| PECO | Transmission Zone | PA | PECO (Exelon) | MIDATL | PJM-RTO, MAD |
| PEPCO | Transmission Zone | DC, MD | PEPCO (Exelon) | MIDATL | PJM-RTO, MAD |
| PJM-RTO | RTO | DC, DE, IL, IN, KY, MD, MI, NC, NJ, OH, PA, TN, VA, WV | PJM Interconnection | | PJM-RTO |
| PPL | Transmission Zone | PA | PPL Electric Utilities | MIDATL | PJM-RTO, MAD |
| PSEG | Transmission Zone | NJ | PSE&G (PSEG) | MIDATL | PJM-RTO, MAD |
| RECO | Transmission Zone | NJ | Orange & Rockland: Rockland Electric Company | MIDATL | PJM-RTO, MAD |
| SMECO | Transmission Zone | MD | Southern Maryland Electric Cooperative | MIDATL | PJM-RTO, MAD |
| SOUTHERN | Region | NC, VA | PJM Southern Region | PJM-RTO | PJM-RTO |
| SRE | Transmission Zone | NJ | Silver Run Electric, subsidiary of LS Power | MIDATL | PJM-RTO, MAD |
| UGI | Transmission Zone | PA | UGI Electric Service | MIDATL | PJM-RTO, MAD |
| WESTERN | Region | IL, IN, KY, MD, MI, OH, PA, TN, VA, WV | PJM Western Region | PJM-RTO | PJM-RTO |
| WVPAT | Transmission Zone | IN | Wabash Valley Power Authority | WESTERN | PJM-RTO |