| Utility | State | Customers | Residential rate |
|---|
| M J M Electric Cooperative Inc | IL | 9,591 | — |
| Macon Electric Coop | MO | 11,690 | 15.75¢ |
| Madison Gas & Electric Co | WI | 168,439 | 21.11¢ |
| Madisonville Municipal Utils | KY | 8,453 | 11.92¢ |
| Magic Valley Electric Coop Inc | TX | 149,858 | 10.51¢ |
| Magnolia Electric Power Assn | MS | 33,448 | 16.06¢ |
| Maison Energy LLC | TX | 1,153 | 15.30¢ |
| Major Energy Electric Services | OH | 29,190 | 12.96¢ |
| Manitowoc Public Utilities | WI | 18,234 | 11.44¢ |
| Maquoketa Valley Rrl Elec Coop | IA | 17,339 | 13.80¢ |
| Marathon Power LLC | NY | 5 | 10.00¢ |
| Marias River Electric Coop Inc | MT | 3,819 | — |
| Maricopa County M W C Dist #1 | AZ | 100 | — |
| Marin Clean Energy | CA | 594,597 | 15.00¢ |
| Marshall County Rural E M C | IN | 7,472 | — |
| Marshall-De Kalb Electric Coop | AL | 21,523 | 13.15¢ |
| Maryville Utilities | TN | 22,640 | 12.11¢ |
| Massachusetts Bay Trans Authority | MA | 68 | — |
| Massachusetts Electric Co | MA | 486,042 | 33.66¢ |
| Matanuska Electric Assn Inc | AK | 72,296 | 24.54¢ |
| Matinicus Plantation Elec Co | ME | 132 | — |
| Maui Electric Co Ltd | HI | 71,962 | 41.97¢ |
| Maven Energy, LLC | MA | 316 | 15.69¢ |
| MC Squared Energy Services, LLC | IL | 293,923 | 8.14¢ |
| McCone Electric Coop Inc | MT | 5,481 | — |
| McCook Public Power District | NE | 5,120 | — |
| McDonough Power Coop | IL | 4,980 | — |
| McGrath Light & Power Co | AK | 256 | — |
| McKenzie Electric Coop Inc | ND | 13,829 | 8.03¢ |
| McLean Electric Coop, Inc | ND | 4,303 | 14.64¢ |
| McLeod Cooperative Power Assn | MN | 7,089 | — |
| McMinnville Electric System | TN | 8,370 | 12.98¢ |
| McMullen Valley Water C&D Dist | AZ | 191 | — |
| Meade County Rural E C C | KY | 31,806 | 15.26¢ |
| Meadow Town Corporation | UT | 169 | — |
| Mecklenburg Electric Cooperative | VA | 32,151 | 14.32¢ |
| Median Energy Corp. | NY | 13,258 | 19.74¢ |
| Median Energy PA LLC | PA | 1,046 | 18.61¢ |
| Medina Electric Coop, Inc | TX | 38,282 | 12.54¢ |
| Meeker Coop Light & Power Assn | MN | 9,345 | 14.03¢ |
| Melrose Public Utilities | MN | 1,927 | — |
| MEMS Industrial Supply, LLC | TX | 26 | — |
| Menard Electric Coop | IL | 10,984 | 19.45¢ |
| Merced Irrigation District | CA | 13,671 | 24.15¢ |
| Meriwether Lewis Electric Coop | TN | 37,018 | 14.24¢ |
| Messer Energy Services, Inc. | OH | 14 | — |
| Metlakatla Power & Light | AK | 1,024 | — |
| Miami Special Utility Authority | OK | 6,829 | — |
| Miami-Cass County Rural E M C | IN | 6,129 | — |
| Mid-Carolina Electric Coop Inc | SC | 61,196 | 16.83¢ |
| Mid-Ohio Energy Coop, Inc | OH | 8,231 | — |
| Mid-South Electric Coop Assn | TX | 42,522 | 15.37¢ |
| Mid-Yellowstone Elec Coop, Inc | MT | 2,053 | — |
| MidAmerican Energy Co | IA | 838,069 | 11.08¢ |
| MidAmerican Energy Services, LLC | TX | 1,313 | 15.10¢ |
| Middle Georgia El Member Corp | GA | 8,634 | — |
| Middle Kuskokwim Elec Coop Inc | AK | 179 | — |
| Middle Tennessee E M C | TN | 348,660 | 12.47¢ |
| Midland Power Coop | IA | 12,708 | 13.66¢ |
| Midstate Electric Coop, Inc | OR | 21,885 | 11.85¢ |
| Midvale Irrigation District | WY | 5 | — |
| Midwest Electric Member Corp - (NE) | NE | 5,911 | 12.03¢ |
| Midwest Electric, Inc - (OH) | OH | 11,247 | 15.77¢ |
| Midwest Energy Cooperative - (MI) | MI | 37,183 | 19.46¢ |
| Midwest Energy Inc - (KS) | KS | 50,200 | 12.01¢ |
| MiEnergy Cooperative | MN | 23,706 | 16.99¢ |
| Mille Lacs Energy Cooperative | MN | 16,058 | 17.50¢ |
| Minnesota Valley Coop L&P Assn | MN | 5,323 | 13.23¢ |
| Minnesota Valley Electric Coop | MN | 48,531 | 14.39¢ |
| Mirabito Power & Gas, LLC | NY | 2,877 | 9.65¢ |
| Mississippi County Electric Co | AR | 4,965 | 9.40¢ |
| Mississippi Power Co | MS | 193,135 | 15.69¢ |
| Missoula Electric Coop, Inc | MT | 16,781 | 10.93¢ |
| Missouri Rural Electric Coop | MO | 5,659 | 14.24¢ |
| Mitchell Electric Member Corp | GA | 25,773 | 17.12¢ |
| Modern Electric Water Company | WA | 11,299 | 7.67¢ |
| Modesto Irrigation District | CA | 134,563 | 23.03¢ |
| Mohave Electric Cooperative, Inc. | AZ | 46,326 | 11.27¢ |
| Mohawk Municipal Comm | NY | 1,318 | — |
| Mohegan Tribal Utility Authority | CT | 75 | — |
| Monongahela Power Co | WV | 397,362 | 14.31¢ |
| Monroe County Elec Coop, Inc | IL | 7,584 | — |
| Monroe County Elec Power Assn | MS | 11,909 | 13.15¢ |
| Mont Alto Borough | PA | 718 | — |
| Montana-Dakota Utilities Co | ND | 146,550 | 11.47¢ |
| Moon Lake Electric Assn Inc | UT | 20,620 | 9.34¢ |
| Moose Lake Water & Light Comm | MN | 920 | — |
| Mor-Gran-Sou Electric Coop Inc | ND | 10,441 | — |
| Mora-San Miguel Elec Coop | NM | 11,604 | — |
| Moreau-Grand Electric Coop Inc | SD | 7,161 | — |
| Morenci Water and Electric | AZ | 2,637 | 6.02¢ |
| Morgan City - (LA) | LA | 5,639 | — |
| Morgan City - (UT) | UT | 2,111 | — |
| Morgan County Rural Elec Assn | CO | 9,650 | 14.46¢ |
| Morgan Stanley Capital Grp Inc | TX | 2 | — |
| Mothership | TX | 15,922 | 14.92¢ |
| Mountain Electric Coop, Inc | NC | 36,481 | 13.13¢ |
| Mountain Parks Electric, Inc | CO | 23,368 | 17.54¢ |
| Mountain View Elec Assn, Inc | CO | 65,946 | 15.65¢ |
| Mountrail-Williams Elec Coop | ND | 19,199 | 7.25¢ |
| MP2 Energy LLC | TX | 16,148 | 12.99¢ |
| MPD Electric Cooperative | SC | 38,905 | 13.73¢ |
| MPower Energy LLC | NY | 31,537 | 19.43¢ |
| MPower Energy NJ LLC | PA | 21,488 | 19.11¢ |
| Mt Carmel Public Utility Co | IL | 5,236 | 19.68¢ |
| Mt Wheeler Power, Inc | NV | 7,762 | 9.45¢ |