| LDV Consultants Inc. | Chambly | QC | Subcontractor |
| Lean Commissioning Group, LLC | Seattle | WA | Subcontractor |
| Lean Goat LLC | Rapid City | MI | Subcontractor |
| Lean Technology Corp. | Costa Mesa | CA | Subcontractor |
| Lectromechanical Design Company LLC | Chantilly | VA | Subcontractor |
| Lee & Ro, Inc. | City Of Industry | CA | Subcontractor |
| Leftside Rightside LLC | Alexandria | VA | Subcontractor |
| Legacy Collaborative, LLC | Birmingham | AL | Subcontractor |
| Legacy Consulting Services, LLC | Belcamp | MD | Subcontractor |
| Leidos Engineering LLC | Tulsa | OK | $0 |
| Leidos Engineering, LLC | Saint Louis | MO | $0 |
| Leidos Integrated Technology LLC | Gaithersburg | MD | $0 |
| Leidos Integrated Technology, LLC | Reston | VA | $0 |
| Lemar Holding Company LLC | La Mesa | CA | Subcontractor |
| Leonard Jackson Pe PLLC | East Quogue | NY | Subcontractor |
| Leonard Technical Services, LLC | Newburg | MD | Subcontractor |
| Lerch Bates Inc. | Highlands Ranch | CO | Subcontractor |
| Le Structures Corporation | Wichita | KS | Subcontractor |
| Levron Engineering Services LLC | Cokato | MN | Subcontractor |
| L. E. Wooten & Co. | Raleigh | NC | Subcontractor |
| Lexawork LLC | Georgetown | TX | Subcontractor |
| LG2WB Engineers, Inc. | Irvine | CA | Subcontractor |
| Lichtig Emc Consulting LLC | Bridgewater | NJ | Subcontractor |
| Liebert Consulting LLC | Plano | TX | Subcontractor |
| Lifecycle Defense Solutions LLC | Madison | AL | Subcontractor |
| Liftech Consultants Inc. | Oakland | CA | Subcontractor |
| Lightworker Photonics LLC | The Villages | FL | Subcontractor |
| Ligos Joseph | Ashburn | VA | Subcontractor |
| Limbach Facility Services LLC | Warrendale | PA | Subcontractor |
| Lim Construction Materials Testing Inc. | Buffalo Grove | IL | $0 |
| Lime & Green Engineering LLC | New Port Richey | FL | $0 |
| Lin Consulting Inc. | Diamond Bar | CA | Subcontractor |
| Linear Labs LLC | Washington | DC | Subcontractor |
| Lin Jennifer | Sammamish | WA | Subcontractor |
| Linkan Engineering, Ltd. | Elko | NV | $0 |
| Link, LLC | Davidsonville | MD | $0 |
| Lippincott Wendy | Annandale | VA | Subcontractor |
| Liro Engineers Inc. | Syosset | NY | Subcontractor |
| Lja Engineering Inc. | Houston | TX | Subcontractor |
| L.k. Mclean Associates Engineering & Surveying DPC | Brookhaven | NY | Subcontractor |
| Lli Engineering Inc. | Pittsburgh | PA | $0 |
| Lloyd Engineering, Inc. | Bellaire | TX | Subcontractor |
| Lloyd's Register Americas Advisory Services, Inc. | Magnolia | TX | Subcontractor |
| LMK Engineers, LLC | Pottstown | PA | $0 |
| LMS 5a Engineering & Consulting LLC | Freehold | NJ | Subcontractor |
| LNV, LLC | Corpus Christi | TX | $0 |
| Local Highway Tech Assist Council | Boise | ID | $0 |
| Lockheed Martin Corp. | Littleton | CO | $0 |
| Lockheed Martin CorporationOldsmar, FL · UEI EW4GCCB6XVH9 | Oldsmar | FL | Subcontractor |
| Lockheed Martin CorporationTampa, FL · UEI V72JALDZTD35 | Tampa | FL | Subcontractor |
| Lockwood Andrews & Newnam Inc. | Houston | TX | Subcontractor |
| Lockwood, Andrews & Newnam, Inc. | Dallas | TX | $0 |
| Logicircuit, Inc. | Cumming | GA | Subcontractor |
| Logistics Engineering And Systems Integration Services, LLC | Boonton | NJ | Subcontractor |
| Logist International L.L.C. | Orlando | FL | $0 |
| Logos Enterprises, Inc. | Huntsville | AL | Subcontractor |
| Lokahi LLC | El Segundo | CA | Subcontractor |
| Lonestar Acoustics LLC | Allen | TX | Subcontractor |
| Long Sought For Design, LLC | Westford | MA | Subcontractor |
| Lonquist & Co. LLC | Austin | TX | Subcontractor |
| Lopez Engineering, Inc. | Lancaster | CA | Subcontractor |
| Lovett Consultants PLLC | Mint Hill | NC | Subcontractor |
| Lower Columbia Engineering LLC | Saint Helens | OR | $0 |
| Loxodrome Consulting LLC | Arlington | VA | Subcontractor |
| LR3 Solutions LLC | Alexandria | VA | Subcontractor |
| LRC Engineering & Surveying, D.P.C. | Poughkeepsie | NY | $0 |
| Lsas Tec Inc. | Vail | AZ | Subcontractor |
| LSC Transportation Consultants, Inc. | Denver | CO | Subcontractor |
| L&S Energy Services, Inc. | Clifton Park | NY | Subcontractor |
| L Stuart, Inc. | Commack | NY | Subcontractor |
| L&T Technology Services LLC | Peoria | IL | Subcontractor |
| Lt-tech Solutions LLC | Melbourne | FL | Subcontractor |
| Lucas Engineering & Management Services, Inc. | Richland | WA | Subcontractor |
| Lumos & Associates, Inc. | Reno | NV | Subcontractor |
| Lusk Engineering LLC | Medford | NJ | Subcontractor |
| Luster National Inc. | Bakersfield | CA | Subcontractor |
| L & W Enterprises, Inc. | Petersburg | WV | $0 |
| Lynk Engineers, LLC | Salt Lake City | UT | Subcontractor |
| Lynx Support Specialist Inc. | Huntsville | AL | Subcontractor |
| Lyon Engineering & Surveying, Inc. | Prescott | AZ | $0 |
| M5 Engineering Inc. | Macomb | MI | Subcontractor |
| Macarthur Associated Consultants, LLC | Oklahoma City | OK | Subcontractor |
| Macdonald Engineers, Inc. | Vista | CA | Subcontractor |
| Mach 1 Ops LLC | Huntsville | AL | Subcontractor |
| Machado-patano PLLC | Biloxi | MS | Subcontractor |
| Mac Millan Associates Inc. | Bay City | MI | $0 |
| Macy Consulting, Inc. | Saint Peters | MO | Subcontractor |
| Madrid Engineering Group, Inc. | Bartow | FL | Subcontractor |
| Ma Engineers, Inc. | San Diego | CA | Subcontractor |
| Magna Engineers PLLC | Lexington | KY | Subcontractor |
| M.a. Grubb & Associates, LLC | Wexford | PA | Subcontractor |
| Mahoney Management Inc. | Middletown | VA | Subcontractor |
| Maida Engineering Inc. | Philadelphia | PA | Subcontractor |
| Main James S | Derwood | MD | $0 |
| Mainnerve Federal Services Inc. | Lexington Park | MD | Subcontractor |
| Makeen Tech Corp. | Killeen | TX | $0 |
| Malcolm W Dinning | Norfolk | VA | Subcontractor |
| Maleki Technologies Inc. | Spokane | WA | Subcontractor |
| Malone Engineering, Inc. | Rapid City | SD | $0 |
| Mammoth Design Group LLC | Morrisville | NC | Subcontractor |
