| Mayfield Compressor Station | Compressor station | Beckham County, OK | Oneok Gas Transportation, LLC | |
| Maysville Natural Gas Processing | Gas processing plant | Garvin County, OK | ONEOK Inc., Oneok Field Services Inc | In service |
| McArthur | Underground storage | Vinton County, OH | Columbia Gas Transmission, LLC | In service |
| McCall Terminal Portland | Terminal | OR | McCall Oil & Chemical | |
| McClain Booster Station | Compressor station | Oklahoma County, OK | Petrolink Energy LLC | |
| McClure | Gas processing plant | Custer County, OK | ET Gathering & Processing, LLC, Enable Products LLC | In service |
| McCormick Field Compressor Station | Compressor station | Texas County, OK | Scout Energy Management LLC | |
| McCoy Gas Com D1 CDP | Compressor station | NM | Hilcorp Energy Company | |
| McCurtain Compressor Station | Compressor station | Haskell County, OK | Oneok Gas Transportation, LLC | |
| McDonald Island | Underground storage | San Joaquin County, CA | Pacific Gas and Electric Co | In service |
| McGraw Compressor Station | Compressor station | Coal County, OK | Mla Midstream LLC | |
| McIntosh Salt Dome | Underground storage | Washington County, AL | Bay Gas Storage Co. Ltd. | In service |
| McKay Compressor Station | Compressor station | Pittsburg County, OK | Santa Fe Operating LLC | |
| McKee Compressor Station | Compressor station | Alfalfa County, OK | Targa Pipeline Midcontinent Westok LLC | |
| McKittrick 17Z Plant | Gas processing plant | Kern County, CA | Chevron | In service |
| McLean Gas Plant | Gas processing plant | Gray County, TX | | |
| McLean Plant | Gas processing plant | Gray County, TX | Carrera Operating Company LLC | In service |
| McLouth | Underground storage | Jefferson County, KS | Southern Star Central Gas Pipeline, Inc. | In service |
| McMullen | Gas processing plant | McMullen County, TX | Houston Pipe Line Company LP | In service |
| McWhorter Gas Plant | Gas processing plant | Harris County, TX | | |
| Meadors Compressor Station | Compressor station | Pittsburg County, OK | Abundance Energy Services LLC | |
| Meadow Ridge Development, LLC, Buffalo Run | Compressor station | WV | | |
| Medford Fractionator | Gas processing plant | Grant County, OK | Oneok Hydrocarbon LP | |
| Medina | Underground storage | Medina County, OH | Columbia Gas Transmission, LLC | In service |
| Meeker Gas Plant | Gas processing plant | Rio Blanco County, CO | Enterprise Gas Processing, LLC | In service |
| Meenan Oil Cortland Manor terminal | Terminal | NY | Meenan Oil LP | |
| Meenan Oil Poughkeepsie terminal | Terminal | NY | Meenan Oil LP | |
| Meenan Oil Tullytown terminal | Terminal | PA | Meenan Oil LP | |
| Megan Compressor Station | Compressor station | Woods County, OK | Targa Pipeline Midcontinent Westok LLC | |
| Mehan Gas Plant | Gas processing plant | Payne County, OK | Tag Petroleum Inc | In service |
| Mentone Gas Plant | Gas processing plant | Loving County, TX | | |
| Mentone Gas Processing Plant | Gas processing plant | Loving County, TX | | |
| Mentor NGL plant | Gas processing plant | Oscoda County, MI | Merit Energy Company | In service |
| Mercy Gas Plant | Gas processing plant | San Jacinto County, TX | Forest Oil Corp | In service |
| Meredosia terminal | Terminal | IL | Meredosia Terminal | |
| Meridian Compressor Station | Compressor station | Hughes County, OK | VM Arkoma Stack, LLC | |
| Merrick Booster Station | Compressor station | Roger Mills County, OK | Markwest Oklahoma Gas Company, LLC | |
| Merritt Compressor Station | Compressor station | Beckham County, OK | Palo Duro G And P Oklahoma LP | |
| Mertz Plant | Gas processing plant | Lavaca County, TX | | |
| Mertzon Plant | Gas processing plant | Irion County, TX | Targa Resources | In service |
| Mesquite Terminal | Gas processing plant | Midland County, TX | | |
| Mestena Drip | Compressor station | Jim Hogg County, TX | | |
| Mewbourne | Gas processing plant | Weld County, CO | DCP Operating Company, LP | In service |
| Meyer Compressor Station | Compressor station | Garvin County, OK | Enerfin Gathering LLC | |
| MiVida JV Processing Plant | Gas processing plant | Ward County, TX | ETC Field Services LLC | In service |
| Miami Quarry 32 Portable Plant 6 | Gas processing plant | Ottawa County, OK | Midwest Minerals Inc | |
| Mid Continent Frac & Storage Conway Frac terminal | Terminal | KS | Mid Continent Frac & Storage | |
| Mid-America Pipeline Clay Center Terminal | Terminal | KS | Mid-America Pipeline Co LLC | |
| Mid-America Pipeline Co Llcente Iowa City Terminal | Terminal | IA | Mid-America Pipeline Co Llcente | |
| Middleberg Booster Station | Compressor station | Grady County, OK | DCP Operating Company, LP | |