| Liberty Fire Protection Inc. | Rosharon | TX | $0 |
| Life Safety Systems, Inc. | Blaine | MN | Subcontractor |
| Linder & Associates Inc. | Wichita | KS | $0 |
| Linder Electric, Inc. | Abilene | KS | $0 |
| Lindquist Electric Inc. | Ironwood | MI | $0 |
| Lindsey Electric Inc. | Springfield | IL | Subcontractor |
| Line-load Electrical Contractor's Inc. | Waldorf | MD | Subcontractor |
| Link Electric Inc. | Spartanburg | SC | $0 |
| Listen Up, Inc. | Denver | CO | $0 |
| Littlejohn-reuland Corporation | Vernon | CA | $0 |
| Little's Quality Contracting Inc. | Washington | DC | $0 |
| Livaudais Electrical & Construction LLC | Meraux | LA | $0 |
| Live Electric Inc. | Las Vegas | NV | $0 |
| L J Construction Inc. | Kinston | NC | Subcontractor |
| LMH & LMH, L.L.C. | Mcallen | TX | Subcontractor |
| Local Electric, Incorporated | Kodiak | AK | Subcontractor |
| Logan Electric Service, Inc. | Fredericksburg | VA | $0 |
| Lothar Schmitt | Bonn | | $0 |
| Lowrie Electric Company, Inc. | Bartlett | TN | $0 |
| Loyd Electric & Ag Supply LLC | Sesser | IL | $0 |
| Lri/gf Sba-m/p JV, LLC | Gambrills | MD | Subcontractor |
| Lt Technology Solutions LLC | Wichita | KS | Subcontractor |
| Ludwar Elektrobau GMBH | Gerolzhofen | | $0 |
| Lumenal Lighting, LLC | Mountlake Terrace | WA | $0 |
| Lumin8 Transportation Technologies LLC | Arvada | CO | Subcontractor |
| Luxterra Electrical, Inc. | Toano | VA | Subcontractor |
| Lyle Northern Electric, Inc. | Blanding | UT | $0 |
| Lynco Electric Company, Inc. | Las Cruces | NM | Subcontractor |
| Lyndhurst Electrical & Mechanical Contracting Corp. | Wayne | NJ | Subcontractor |
| M2 Automation & Control Services, Inc. | Boise | ID | Subcontractor |
| Magnum Electric Inc. | West Fargo | ND | $0 |
| Maguire Electrical Construction, L.L.C. | Mays Landing | NJ | $0 |
| Malko Communication Services, LLC | Chicago | IL | Subcontractor |
| Mallory Electric Co. | Newport News | VA | Subcontractor |
| Managed Solutions Inc. | Suwanee | GA | Subcontractor |
| Mann Wireless, Inc. | Largo | FL | $0 |
| Maral Engineering Corp. | Mayaguez | PR | Subcontractor |
| Mardant Electrical Construction Company, Inc. | Jacksonville | FL | Subcontractor |
| Mark E. Jennings Electric, LLC | Hollywood | MD | Subcontractor |
| Mark One Electric Co. Inc. | Kansas City | MO | Subcontractor |
| Mark's Electric, Inc. | Detroit Lakes | MN | $0 |
| Mark The Electrician, Inc. | Los Alamos | NM | Subcontractor |
| Mark Whitehead Electrical Contractor, Inc. | Kingsley | PA | $0 |
| Marsh Electric LLC | Shawnee | OK | $0 |
| Martell Electric LLC | South Bend | IN | Subcontractor |
| Martir Electric Service Corp. | Mayaguez | PR | $0 |
| Masiongale Electrical-mechanical, Inc. | Muncie | IN | $0 |
| Massey Construction, Inc. | Alcoa | TN | Subcontractor |
| Master Communications, Inc. | Ellisville | MO | $0 |
| Master Craft Electrical Service LLC | Charlotte Hall | MD | Subcontractor |
| Master Craft Electric, Inc. | Pacific | WA | Subcontractor |
| Master Electric, Inc. | Mountain Home | ID | $0 |
| Matson Alarm Co. Inc. | Fresno | CA | $0 |
| Matthew Davenport | Morrison | TN | Subcontractor |
| Mattingly Electric LLC | Petersburg | AK | Subcontractor |
| Maverick Communications, Inc. | Beaumont | TX | $0 |
| Max Electrical Construction Corp. | Savage | MD | Subcontractor |
| Mayda & Sons, LLC | Silverdale | WA | Subcontractor |
| M.b. Herzog Electric, Inc. | Paramount | CA | Subcontractor |
| MC2 Electrical Contractors LLC | Denver | CO | $0 |
| Mc Atlin Electrical Corp. | Grand Junction | CO | $0 |
| Mccarter Electrical Co. | Laurinburg | NC | Subcontractor |
| Mccay Southern Electrical LLC | Riceville | TN | $0 |
| Mcclelland Inc. | Wichita | KS | $0 |
| Mccrory Electric Company | Memphis | TN | $0 |
| Mcdaniel's A.c. Plumbing & Electrical, Inc. | Grenada | MS | $0 |
| Mcdonald C F Electric Inc. | Houston | TX | Subcontractor |
| Mcdonald Electrical Corporation | Hingham | MA | Subcontractor |
| Mcfadden Electric LLC | Fallon | NV | Subcontractor |
| Mcinnis Electric Co. | Byram | MS | Subcontractor |
| Mc Niel Electric Co. Inc. | Peralta | NM | $0 |
| M-co, LLC | Saint Louis | MO | Subcontractor |
| Md Electric, L.L.C. | Stewartsville | MO | $0 |
| Meade Electric Co. Inc. | Burr Ridge | IL | $0 |
| Mec Electrical & Technologies, Inc. | Chelmsford | MA | $0 |
| Mega-pro, Inc. | San Antonio | TX | Subcontractor |
| Mehl Electric Company, Inc. | Pearl River | NY | $0 |
| Meitec, Inc. | Metairie | LA | Subcontractor |
| M Electric Inc. | Albuquerque | NM | Subcontractor |
| Mel Smith Electric, Inc. | Stanton | CA | Subcontractor |
| Mercury Communications, Incorporated | Stratford | CT | $0 |
| Merit Electrical Group Inc. | Oakmont | PA | Subcontractor |
| Merit Electric Company | Reno | NV | $0 |
| Merit Electric Of Spokane Inc. | Spokane | WA | $0 |
| Merkel Company Inc. | Marshfield | WI | $0 |
| Merkel Electric Inc. | Yankton | SD | $0 |
| Mesquite Electric LLC | Mesquite | NV | $0 |
| Metro Electric, Inc. | Mcallen | TX | $0 |
| Metropolitan Audio Visual Co. LLC | Dulles | VA | $0 |
| Metro & Son Electric, Inc. | Sioux City | IA | $0 |
| Meyer Electric & Solar LLC | St John | VI | $0 |
| Meyers Electric LLC | Panama City | FL | Subcontractor |
| MGM Electrical Systems, Inc. | Annapolis | MD | Subcontractor |
| MGQ & Associates, Inc. | Tampa | FL | Subcontractor |
| MGR Electrical Contracting Incorporated | Haverhill | MA | Subcontractor |
| Mh Electric Construction, Inc. | Honolulu | HI | Subcontractor |
| Michael Gonzalez | Santa Maria | CA | Subcontractor |
| Michel Inc. | Clarksburg | WV | $0 |
| Michiana Contracting, Inc. | Plymouth | IN | $0 |
| Midland Electric, Inc. | Davenport | WA | $0 |
