| Boone Cable Works & Electronics, Inc. | Boone | IA | $0 |
| Bopat Electric Co. Inc. | Columbia | MD | $0 |
| Bowings & Huber LLC | Hampstead | MD | $0 |
| Bowman Connectivity Solutions, Inc. | Waipahu | HI | Subcontractor |
| Bowman Electric Shop, Limited | Kailua | HI | $0 |
| Box Electric Company | Raleigh | NC | $0 |
| Boys Electrical Contractors LLC | Melbourne | FL | Subcontractor |
| Brackley Electric Inc. | West Bath | ME | Subcontractor |
| Brandt Electrical Services, Inc. | Katy | TX | $0 |
| Brattan Industries Inc. | Littleton | MA | Subcontractor |
| Brec Electric Co. | Zimmerman | MN | $0 |
| Brian Electric Co. LLC | Pineville | LA | $0 |
| Bridges Electric & Motor Service, Inc. | Dublin | GA | $0 |
| Brieth Electric LLC | Lampasas | TX | Subcontractor |
| Bright Services, Inc. | North Pole | AK | $0 |
| Brite Electrical Services, LLC | Norfolk | VA | Subcontractor |
| Britt Rice Construction Company, LP | College Station | TX | Subcontractor |
| BRK Electrical Contractors, LLC | Bridgeton | MO | Subcontractor |
| Broadband America Corp. | Victoria | MN | $0 |
| Broadway Electric Service Company LLC | Knoxville | TN | Subcontractor |
| Brooks-berry-haynie & Associates, Inc. | Mableton | GA | Subcontractor |
| Brotherlylove Electric, LLC | Hockley | TX | Subcontractor |
| Brown Electric Construction Co. | Quincy | IL | Subcontractor |
| Brown Electric Inc. | Waldorf | MD | Subcontractor |
| Brown Guy Fire & Safety Inc. | Dallas | TX | $0 |
| Brown & Heim Inc. | Halethorpe | MD | $0 |
| Brown & Son, LLC | Phenix City | AL | Subcontractor |
| Bruce-merrilees Electric LLC | New Castle | PA | $0 |
| Bruce's Electric, Inc. | Long Beach | MS | Subcontractor |
| Bryant-berry Inc. | Beltsville | MD | Subcontractor |
| Bt Ludeke, Inc. | Holdrege | NE | $0 |
| BTS, Inc. | Dubuque | IA | $0 |
| BTV Systems, Inc. | Macon | GA | $0 |
| Buckler Electric LLC | Mechanicsville | MD | $0 |
| Buckler Ventures LLC | Mechanicsville | MD | Subcontractor |
| Buffalo Gap Instrumentation And Electrical Co. Inc. | Abilene | TX | Subcontractor |
| Building Automation Services, LLC | Schenectady | NY | Subcontractor |
| Building Automation Systems LLC | Jarales | NM | $0 |
| Building Electrical Systems, Inc. | Tulsa | OK | $0 |
| Building Electronic Controls, Inc. | Glendora | CA | Subcontractor |
| Building Network Solutions, Inc. | Bradenton | FL | $0 |
| Buildron Corporation | Tamuning | GU | Subcontractor |
| Bulkley Electric, Inc. | Helena | MT | $0 |
| Bullet Communications Inc. | Elmwood Park | NJ | $0 |
| Burchfield Electric, Inc. | Saint Augustine | FL | $0 |
| Burnell Controls, Inc. | Danvers | MA | $0 |
| Buss Electric, Inc. | Greenville | WI | $0 |
| Bustard Communications | Marysville | CA | Subcontractor |
| Cable Communications Of Arkansas Inc. | North Little Rock | AR | Subcontractor |
| Cabling Concepts, Inc. | Edmond | OK | $0 |
| Cabling Solutions Inc. | Stanley | NC | $0 |
| Cabot Electric And Construction Company, Inc. | Ward | AR | Subcontractor |
| Cacy Electric | El Cajon | CA | Subcontractor |
| Caedmon Construction & Electrical Co. LLC | Kansas City | MO | $0 |
| California Professional Engineering Inc. | City Of Industry | CA | $0 |
| California Safety Company, Inc. | Redding | CA | $0 |
| Calray Electric, Inc. | Solana Beach | CA | Subcontractor |
| Caltech Systems Inc. | Queen Creek | AZ | $0 |
| Calvi Electric Company | Egg Harbor Township | NJ | Subcontractor |
| C.a.m. Electric, Inc. | Montrose | CO | $0 |
| Camtek Inc. | Spokane | WA | $0 |
| Candela Controls, Inc. | Winter Garden | FL | $0 |
| Cannon & Wendt Electric Co. Inc. | Tucson | AZ | Subcontractor |
| Canseco Electrical Contractors, Inc. | Miami | FL | Subcontractor |
| Canyon Electric LLC | Billings | MT | $0 |
| Capital City Communications LLC | West Columbia | SC | $0 |
| Capital Electric, Inc. | Evansville | IN | Subcontractor |
| Capital Electric Line Builders, Inc. | Parkville | MO | $0 |
| Capitol Cable Communications, Inc. | Upper Marlboro | MD | Subcontractor |
| Capron Company, Inc. | Rockville | MD | $0 |
| Caraway Electric, LLC | Sophia | NC | Subcontractor |
| Carl I. Schaeffer Electric Company | Saint Louis | MO | $0 |
| Carl T. Madsen, Inc. | Tacoma | WA | Subcontractor |
| Carnahan Electric, Ltd. | Diamond Springs | CA | $0 |
| Carr Electrical Technology, Inc. | Newport News | VA | Subcontractor |
| Carrillo Electric Inc. | San Bernardino | CA | Subcontractor |
| Casas Electric Inc. | Las Vegas | NV | $0 |
| Casa Technology Systems, LLC | Phoenix | AZ | $0 |
| Cascade Power Inc. | Olympia | WA | Subcontractor |
| Cascade Power Systems, Corp. | Leavenworth | WA | Subcontractor |
| Casey Electric LLC | Tell City | IN | $0 |
| Casper Electric, Inc. | Casper | WY | $0 |
| Castrejon Inc. | Minneapolis | MN | $0 |
| Caszone, LLC | Winchester | VA | $0 |
| C&B Construction Inc. | Juneau | AK | $0 |
| C & D Electric, Inc. | Colorado Springs | CO | Subcontractor |
| Cdi Ventures, Inc. | San Antonio | TX | Subcontractor |
| CDL Electric Company, Inc. | Pittsburg | KS | $0 |
| Cec Facilities, LLC | Irving | TX | Subcontractor |
| Centerburg Technology Center | Centerburg | OH | $0 |
| Central Arkansas Telephone Cooperative Inc. | Donaldson | AR | $0 |
| Central Electric, Inc. | Lewistown | MT | Subcontractor |
| Central Illinois Electrical Services, LLC | Bartonville | IL | $0 |
| Central Power LLC | Highlands Ranch | CO | Subcontractor |
| Central Power Solution Corp. | Comerio | PR | $0 |
| Certified Electric Inc. | Brunswick | GA | Subcontractor |
| C & G Electric Inc. | Krum | TX | $0 |
| Chammings Electric Inc. | Vineland | NJ | $0 |
| Charles Kirkham | Climax | MI | $0 |
| Charlie Mann Electric, Inc. | Gambrills | MD | Subcontractor |
