| Diclemente Siegel Design Inc. | Southfield | MI | $0 |
| Digiflight Incorporated | Huntsville | AL | Subcontractor |
| Digital Engineering & Imaging Inc. | Kenner | LA | $0 |
| Dimensional Certification, Inc. | Northville | MI | $0 |
| Dinter Engineering Co. | Reno | NV | Subcontractor |
| Directed Energy Technologies Inc. | Sumerduck | VA | Subcontractor |
| Dir Solutions, LLC | Scottsboro | AL | Subcontractor |
| Discovery Democracy LLC | Rancho Palos Verdes | CA | Subcontractor |
| Discovery Joint Venture | San Diego | CA | $0 |
| Distinct Engineering Solutions Inc. | North Brunswick | NJ | Subcontractor |
| Diversified Laboratory Sciences, Inc. | Marietta | GA | Subcontractor |
| Diversified Project Services International, Inc. | Bakersfield | CA | Subcontractor |
| Diversified Technology Consultants, Inc. | Sarasota | FL | $0 |
| Dixie Mountain Dynamics Inc. | Gaston | OR | Subcontractor |
| Dj&a, P.C.Vancouver, WA · UEI E7XFM612B573 | Vancouver | WA | Subcontractor |
| Dj&a, P.C.Lakewood, CO · UEI KK3YMVEK61X8 | Lakewood | CO | Subcontractor |
| DKK Co. Inc. | Gilbert | AZ | Subcontractor |
| Dk Low & Associates LLC | Earlysville | VA | Subcontractor |
| DKS Associates, Inc. | Portland | OR | Subcontractor |
| D.k. Schmidt & Associates LLC | Monument | CO | $0 |
| D.l. Adams Associates Kc, LLC | Denver | CO | Subcontractor |
| DLZ Michigan, Inc. | Lansing | MI | $0 |
| DLZ Ohio, Inc. | Columbus | OH | $0 |
| DMC Consulting, Inc. | Westminster | MD | $0 |
| DMD Consulting Engineers Limited | Surrey | BC | Subcontractor |
| Dna Consulting LLC | Charleston | SC | Subcontractor |
| Dominion Engineering, Inc. | Reston | VA | Subcontractor |
| Dominion Environmental Group, Inc. | Midlothian | VA | $0 |
| Done Design Inc. | Aberdeen | MD | Subcontractor |
| Donovan-hill Group, Inc. | Pensacola | FL | Subcontractor |
| Doosanenerbility Co. Ltd. | Changwon-si | GYEONGNAM | $0 |
| Dopplertech Inc. | Tooele | UT | Subcontractor |
| Dorazio Defense Systems, LLC | Naples | FL | Subcontractor |
| Doron Eshel - Consulting Engineering Ltd. | Herzliya | | Subcontractor |
| Dorsey & Dorsey Engineering, Inc. | Mobile | AL | $0 |
| Dowl LLC | Juneau | AK | $0 |
| Dowl, LLC | Bozeman | MT | Subcontractor |
| Downey And Scott LLC | Warrenton | VA | $0 |
| D P Associates, Inc. | Huntsville | AL | Subcontractor |
| Dp-nxa Consultants, LLC | Fort Worth | TX | Subcontractor |
| Drake Integrations, LLC | Hayden | ID | Subcontractor |
| Dreiym Engineering PLLC | Coldspring | TX | $0 |
| Drexel, Barrell & Co. | Lafayette | CO | $0 |
| DRG Technical Solutions LLC | Memphis | TN | Subcontractor |
| Drive System Design Inc. | Farmington Hills | MI | Subcontractor |
| DRM International, Inc. | Washington | DC | $0 |
| DRMP, Inc. | Orlando | FL | Subcontractor |
| Drysdale & Associates Inc. | Cincinnati | OH | $0 |
| Dsec Co. Ltd. | Busan | | Subcontractor |
| Dtcubed, LLC | Sewell | NJ | Subcontractor |
| Dudek | Encinitas | CA | Subcontractor |
| Duerksen Noel | Spring Hill | KS | $0 |
| Duke Marine Engineering Consulting, Inc. | Stuart | FL | Subcontractor |
| Dulles Engineering Inc. | Aldie | VA | Subcontractor |
| Dulles Geotechnical And Material Testing Services, Inc. | Chantilly | VA | Subcontractor |
| Dulohery Weeks & Gagliano Inc. | Savannah | GA | Subcontractor |
| Dungan Engineering Pa | Columbia | MS | $0 |
| Dunham Associates, Inc. | Minneapolis | MN | $0 |
| Duplantis Design Group Professional Corp. | Thibodaux | LA | Subcontractor |
| Durability Engineers PLLC | Grand Rapids | MI | Subcontractor |
| Duval Engineering LLC | Redmond | OR | Subcontractor |
| DVK Integrated Services, Inc. | San Jose | CA | Subcontractor |
| D.w. Kozera, Inc. | Baltimore | MD | Subcontractor |
| Dynamic Analytical Solutions LLC | Branford | CT | Subcontractor |
| Dynamic Analytics & Test, Inc. | Arlington | VA | Subcontractor |
| Dynamic Systems, Inc. | Tampa | FL | Subcontractor |
| Dynatech Engineering, Inc. | Auburn | CA | $0 |
| Dynetics, Inc. | Colorado Springs | CO | Subcontractor |
| E2cr Inc. | Halethorpe | MD | Subcontractor |
| E4 Technology Inc. | Huntsville | AL | Subcontractor |
| Eac Consulting Inc. | Miami | FL | $0 |
| Eac Design Inc. | Minneapolis | MN | Subcontractor |
| Earth Exploration Inc. | Indianapolis | IN | Subcontractor |
| Earth Mechanics, Inc. | Fountain Valley | CA | Subcontractor |
| Earthquake Safety Solutions | Lalitpur | | Subcontractor |
| Earth Space Technology Service LLC | Upper Marlboro | MD | Subcontractor |
| Earth Systems Pacific | San Luis Obispo | CA | Subcontractor |
| Eba Engineering, Inc. | Laurel | MD | Subcontractor |
| Ebechtle LLC | Suwanee | GA | $0 |
| Ebs Engineering, Inc. | Miami Lakes | FL | Subcontractor |
| Echogen Power Systems (delaware), Inc. | Akron | OH | $0 |
| Echogen Power Systems Inc. | Akron | OH | $0 |
| Echota Research & Science Applications LLC | Athens | AL | $0 |
| Econn Technologies LLC | San Tan Valley | AZ | $0 |
| Ecos Consulting LLC | Ocean | NJ | Subcontractor |
| Ecostrategies Engineering & Surveying PLLC | Falconer | NY | $0 |
| Ecosystem Restoration Services, LLC | White Salmon | WA | Subcontractor |
| Ecs Florida LLC | Orlando | FL | Subcontractor |
| Ecs Mid-atlantic LLC | Fredericksburg | VA | Subcontractor |
| Ecs Midwest, LLC | Buffalo Grove | IL | Subcontractor |
| Ecs Southwest, LLP | Carrollton | TX | Subcontractor |
| Ecxteam LLC | Granbury | TX | Subcontractor |
| Edc Inc. | Anchorage | AK | Subcontractor |
| E & D Engineering Inc. | Ann Arbor | MI | Subcontractor |
| Edf Company Inc. | West Palm Beach | FL | Subcontractor |
| Edg2, Inc. | Bethesda | MD | Subcontractor |
| Edge Consulting Engineers, Inc. | Prairie Du Sac | WI | $0 |
| Edgewater Resources, LLC | Saint Joseph | MI | $0 |
| Edison Energy Group L.L.C | Guaynabo | PR | Subcontractor |
| Edm Incorporated | Saint Louis | MO | $0 |
