Top 100 Contractors in PSC R4: Professional Services, FY2021

Name: Top 100 Contractors in PSC R4: Professional Services, FY2021
Creator: GovTribe

Parent companies by net contract obligations Oct 1, 2020 – Sep 30, 2021 Code page on GovTribe

The top 10 won 21% of FY2021 PSC R4 contract dollars

Contract obligations: $73,439,519,257 Net of deobligations, by contracts coded PSC R4 or a code under it
Contractors: 13,350 Parent companies with an obligation
Largest contractor: Booz Allen Hamilton Holding Corporation $2.68 billion, 3.4% of obligations
Data as of: Oct 14, 2026

Contract actions from FPDS (SAM.gov). How the rankings work · Download all 100 rows as CSV

Full ranking

Rank	Contractor	Net obligations	Share	Trend
1	Booz Allen Hamilton Holding Corporation 10 awardees, including Booz Allen Hamilton Inc., Liberty It Solutions LLC and Middle Bay Solutions II, LLC Top agencies Army (Department of the Army) Navy (Department of the Navy) USAF (Department of the Air Force)	$2,680,452,954	3.4%	Rank history: #1 in FY2022, #1 in FY2023, #1 in FY2024 and #1 in FY2025; unchanged since FY2020.
2	The Boeing Company 26 awardees Top agencies USAF (Department of the Air Force) Army (Department of the Army) Navy (Department of the Navy)	$2,052,895,270	2.6%	Rank history: #3 in FY2022, #2 in FY2023, #2 in FY2024 and #2 in FY2025; up 1 since FY2020.
3	RTX Corporation 61 awardees, including Raytheon Company and Rockwell Collins, Inc. Top agencies Army (Department of the Army) USAF (Department of the Air Force) Navy (Department of the Navy)	$1,651,961,095	2.1%	Rank history: #8 in FY2022, #13 in FY2023 and not on the FY2024–FY2025 lists; up 15 since FY2020.
4	Chemonics International, Inc. Top agencies USAID (US Agency for International Development)	$1,582,316,118	2.0%	Rank history: #6 in FY2022, #8 in FY2023, #8 in FY2024 and #13 in FY2025; down 2 since FY2020.
5	General Dynamics Corporation 38 awardees, including General Dynamics Information Technology, Inc., General Dynamics Global Force, LLC and Csra LLC Top agencies Army (Department of the Army) Navy (Department of the Navy) DOS (Department of State)	$1,545,988,955	2.0%	Rank history: #4 in FY2022, #3 in FY2023, #3 in FY2024 and #4 in FY2025; unchanged since FY2020.
6	Deloitte LLP 5 awardees, including Deloitte Consulting LLP, Deloitte & Touche LLP and Deloitte Financial Advisory Services LLP Top agencies HHS (Department of Health and Human Services) Treasury (Department of the Treasury) DHS (Department of Homeland Security)	$1,416,657,023	1.8%	Rank history: #11 in FY2022, #11 in FY2023, #4 in FY2024 and #6 in FY2025; up 10 since FY2020.
7	Science Applications International Corporation 15 awardees, including Forfeiture Support Associates LLC, Engility Services, LLC and Halfaker and Associates, LLC Top agencies Navy (Department of the Navy) NASA (National Aeronautics and Space Administration) USAF (Department of the Air Force)	$1,334,225,684	1.7%	Rank history: #5 in FY2022, #4 in FY2023, #5 in FY2024 and #7 in FY2025; down 3 since FY2020.
8	Northrop Grumman Corporation 46 awardees, including Northrop Grumman Systems Corporation Top agencies USAF (Department of the Air Force) Army (Department of the Army) Navy (Department of the Navy)	$1,312,088,882	1.7%	Rank history: #9 in FY2022, #7 in FY2023, #10 in FY2024 and #9 in FY2025; down 2 since FY2020.
9	Leidos Holdings, Inc. 26 awardees, including Leidos, Inc. and Aranea Solutions Inc. Top agencies Army (Department of the Army) DOE (Department of Energy) USSOCOM (United States Special Operations Command)	$1,287,221,805	1.6%	Rank history: #12 in FY2022, #10 in FY2023, #9 in FY2024 and #10 in FY2025; unchanged since FY2020.
10	Rapid Deployment Inc. Top agencies HHS (Department of Health and Human Services) Navy (Department of the Navy)	$1,283,198,668	1.6%	Rank history: #2 in FY2022, #23 in FY2023 and not on the FY2024–FY2025 lists; up 85 since FY2020.
11	Lockheed Martin Corporation 32 awardees, including Lockheed Martin Services, LLC and Sikorsky Aircraft Corporation Top agencies USAF (Department of the Air Force) Army (Department of the Army) Navy (Department of the Navy)	$1,224,647,507	1.6%	Rank history: #7 in FY2022, #5 in FY2023, #6 in FY2024 and #5 in FY2025; down 1 since FY2020.
12	The Aerospace Corporation Top agencies USAF (Department of the Air Force) Commerce (Department of Commerce) DOI (Department of the Interior)	$1,049,971,968	1.3%	Rank history: #13 in FY2022, #9 in FY2023, #11 in FY2024 and #11 in FY2025; down 5 since FY2020.
13	CACI International Inc. 20 awardees, including Caci, Inc. - Federal, Caci Nss, LLC and Caci Technologies, LLC Top agencies Army (Department of the Army) Navy (Department of the Navy) DTRA (Defense Threat Reduction Agency)	$1,041,007,637	1.3%	Rank history: #10 in FY2022, #6 in FY2023, #7 in FY2024 and #3 in FY2025; down 1 since FY2020.
14	Maximus Inc. 6 awardees, including Maximus Federal Services, Inc., Q2 Administrators, LLC and Maximus Federal Technology Solutions, LLC Top agencies HHS (Department of Health and Human Services) VA (Department of Veterans Affairs) SSA (Social Security Administration)	$980,263,992	1.2%	Rank history: #15 in FY2022, #14 in FY2023 and not on the FY2024–FY2025 lists; up 3 since FY2020.
15	The Mitre Corporation 2 awardees Top agencies USAF (Department of the Air Force) DOT (Department of Transportation) HHS (Department of Health and Human Services)	$826,686,721	1.1%	Rank history: #14 in FY2022, #12 in FY2023, #14 in FY2024 and #20 in FY2025; down 7 since FY2020.
16	Accenture Federal Services LLC 5 awardees, including ASM Research, LLC, Accenture LLP and Avanade Inc. Top agencies VA (Department of Veterans Affairs) ED (Department of Education) DHS (Department of Homeland Security)	$800,020,894	1.0%	Rank history: #35 in FY2022 and not on the FY2023–FY2025 lists; up 7 since FY2020.
17	L3Harris Technologies, Inc. 37 awardees, including L3Harris Technologies Integrated Systems L.P., L3 Technologies, Inc. and CAE USA Inc. Top agencies USAF (Department of the Air Force) Army (Department of the Army) USSOCOM (United States Special Operations Command)	$733,424,843	0.9%	Rank history: #16 in FY2022, #17 in FY2023, #24 in FY2024 and #23 in FY2025; down 3 since FY2020.
18	Mantech International Corporation 8 awardees, including Mantech Advanced Systems International, Inc., Mantech SRS Technologies, Inc. and Mantech Mgs, Inc. Top agencies Army (Department of the Army) DOJ (Department of Justice) USAF (Department of the Air Force)	$599,450,546	0.8%	Rank history: #18 in FY2022, #42 in FY2023, #47 in FY2024 and #33 in FY2025; up 1 since FY2020.
19	Jacobs Engineering Group Inc. 23 awardees, including Amentum Technology, Inc., Ch2M Hill - CDM Pa-Tac Recovery Services and Ch2M Facility Support Services, LLC Top agencies NASA (National Aeronautics and Space Administration) Army (Department of the Army) DHS (Department of Homeland Security)	$582,739,283	0.7%	Rank history: #24 in FY2022, #28 in FY2023 and not on the FY2024–FY2025 lists; up 6 since FY2020.
20	Amentum Services, Inc. 4 awardees, including Dyncorp International LLC and URS Federal Services International, Inc. Top agencies Navy (Department of the Navy) DOS (Department of State) Army (Department of the Army)	$581,231,193	0.7%	Rank history: #32 in FY2022, #34 in FY2023 and not on the FY2024–FY2025 lists; up 58 since FY2020.
21	Serco North America (Holdings) Inc 7 awardees, including Serco Inc., Serco-Ips Corporation and Whitney Bradley & Brown, Inc. Top agencies Navy (Department of the Navy) HHS (Department of Health and Human Services) DHS (Department of Homeland Security)	$570,878,494	0.7%	Rank history: #17 in FY2022, #32 in FY2023 and not on the FY2024–FY2025 lists; down 1 since FY2020.
22	Parsons Corporation 11 awardees, including Parsons Government Services Inc., Polaris Alpha, LLC and Ptsi Managed Services Inc. Top agencies MDA (DOD Missile Defense Agency) USAF (Department of the Air Force) Army (Department of the Army)	$530,524,661	0.7%	Rank history: #22 in FY2022, #19 in FY2023, #19 in FY2024 and #17 in FY2025; up 2 since FY2020.
23	Guidehouse Inc. 2 awardees Top agencies SBA (Small Business Administration) HHS (Department of Health and Human Services) DOS (Department of State)	$496,380,207	0.6%	Rank history: #29 in FY2022, #25 in FY2023 and not on the FY2024–FY2025 lists; up 14 since FY2020.
24	Kbr, Inc. 11 awardees, including KBR Wyle Services, LLC and Kord Technologies, LLC Top agencies NASA (National Aeronautics and Space Administration) Army (Department of the Army) USAF (Department of the Air Force)	$440,037,516	0.6%	Rank history: #28 in FY2022, #24 in FY2023, #87 in FY2024 and not on the FY2025 list; up 2 since FY2020.
25	BAE Systems PLC 14 awardees, including BAE Systems Technology Solutions & Services Inc., BAE Systems Land & Armaments L.P. and BAE Systems Information and Electronic Systems Integration Inc. Top agencies Army (Department of the Army) USAF (Department of the Air Force) DOJ (Department of Justice)	$439,842,129	0.6%	Rank history: #20 in FY2022, #15 in FY2023, #23 in FY2024 and #21 in FY2025; down 4 since FY2020.
26	General Atomic Technologies Corporation 2 awardees, including General Atomics Aeronautical Systems, Inc. and General Atomics Top agencies USAF (Department of the Air Force) DHS (Department of Homeland Security) DOE (Department of Energy)	$407,832,832	0.5%	Rank history: #33 in FY2022, #37 in FY2023, #40 in FY2024 and not on the FY2025 list; up 2 since FY2020.
27	The Interpublic Group of Companies Inc 5 awardees, including IPG Dxtra, Inc., True North Communications Inc. and Acxiom LLC Top agencies HHS (Department of Health and Human Services) DOS (Department of State)	$395,821,666	0.5%	Rank history: #36 in FY2022, #31 in FY2023, #39 in FY2024 and not on the FY2025 list; up 44 since FY2020.
28	Tetra Tech, Inc. 29 awardees, including Ard, Inc., Management Systems International, Inc. and Tetra TECH ES, Inc. Top agencies USAID (US Agency for International Development) EPA (Environmental Protection Agency) DOT (Department of Transportation)	$375,336,734	0.5%	Rank history: #26 in FY2022, #27 in FY2023, #25 in FY2024 and #34 in FY2025; up 17 since FY2020.
29	Mvm, Inc. Top agencies HHS (Department of Health and Human Services) DOJ (Department of Justice)	$362,396,687	0.5%	Rank history: #25 in FY2022 and not on the FY2023–FY2025 lists; new, not ranked in FY2020.
30	AECOM 15 awardees, including JT4 LLC, AECOM Technical Services, Inc. and AECOM Services, LLC Top agencies USAF (Department of the Air Force) DHS (Department of Homeland Security) Navy (Department of the Navy)	$362,137,264	0.5%	Rank history: #34 in FY2022, #26 in FY2023, #42 in FY2024 and not on the FY2025 list; down 17 since FY2020.
31	Torch Technologies Inc. Top agencies Army (Department of the Army) USAF (Department of the Air Force) MDA (DOD Missile Defense Agency)	$347,457,279	0.4%	Rank history: #51 in FY2022, #43 in FY2023, #46 in FY2024 and #37 in FY2025; down 9 since FY2020.
32	ABT Global LLC 2 awardees Top agencies USAID (US Agency for International Development) HHS (Department of Health and Human Services) ED (Department of Education)	$340,251,831	0.4%	Rank history: #40 in FY2022, #48 in FY2023, #45 in FY2024 and #56 in FY2025; up 2 since FY2020.
33	ICF International, Inc. 4 awardees, including ICF Incorporated, L.L.C., ICF Macro Inc. and Incentive Technology Group LLC Top agencies HHS (Department of Health and Human Services) USAID (US Agency for International Development) EPA (Environmental Protection Agency)	$325,540,012	0.4%	Rank history: #39 in FY2022, #38 in FY2023 and not on the FY2024–FY2025 lists; down 4 since FY2020.
34	America's Blood Centers Top agencies HHS (Department of Health and Human Services)	$325,195,248	0.4%	Rank history: not on the FY2022–FY2025 lists; up 20 since FY2020.
35	PAE Government Services Inc. 9 awardees, including PAE Professional Services, LLC, PAE National Security Solutions LLC and Metis Solutions, LLC Top agencies DOS (Department of State) DOJ (Department of Justice) DHS (Department of Homeland Security)	$312,382,422	0.4%	Rank history: #45 in FY2022, #57 in FY2023 and not on the FY2024–FY2025 lists; up 18 since FY2020.
36	Highlight Technologies, LLC Top agencies SBA (Small Business Administration) USAID (US Agency for International Development) HHS (Department of Health and Human Services)	$307,231,391	0.4%	Rank history: not on the FY2022–FY2025 lists; up 27 since FY2020.
37	Carrington Mortgage Services LLC Top agencies HUD (Department of Housing and Urban Development)	$305,070,658	0.4%	Rank history: not on the FY2022–FY2023 lists, #21 in FY2024 and not on the FY2025 list; down 4 since FY2020.
38	Alion Science and Technology Corporation 3 awardees, including HII Mission Technologies Corp Top agencies USAF (Department of the Air Force) Navy (Department of the Navy) DTRA (Defense Threat Reduction Agency)	$301,944,172	0.4%	Rank history: #77 in FY2022, #33 in FY2023 and not on the FY2024–FY2025 lists; unchanged since FY2020.
39	Research Triangle Institute 2 awardees, including International Resources Group Ltd. Top agencies HHS (Department of Health and Human Services) USAID (US Agency for International Development) EPA (Environmental Protection Agency)	$298,159,318	0.4%	Rank history: #46 in FY2022, #39 in FY2023, #30 in FY2024 and #60 in FY2025; up 1 since FY2020.
40	Selene Finance LP Top agencies HUD (Department of Housing and Urban Development)	$297,712,832	0.4%	Rank history: not on the FY2022–FY2025 lists; down 5 since FY2020.
41	Logistics Management Institute 2 awardees, including The Tauri Group, Inc. Top agencies Army (Department of the Army) DHS (Department of Homeland Security) OSD (Office of the Secretary of Defense)	$288,054,152	0.4%	Rank history: #92 in FY2022 and not on the FY2023–FY2025 lists; down 5 since FY2020.
42	The GEO Group, Inc. 2 awardees, including B.i. Incorporated Top agencies DHS (Department of Homeland Security) DOJ (Department of Justice)	$285,755,254	0.4%	Rank history: #31 in FY2022, #29 in FY2023, #34 in FY2024 and #40 in FY2025; down 10 since FY2020.
43	DAI Global LLC Top agencies USAID (US Agency for International Development)	$267,845,845	0.3%	Rank history: #37 in FY2022, #30 in FY2023, #28 in FY2024 and #48 in FY2025; unchanged since FY2020.
44	Ingenesis Inc. 2 awardees, including Kelly Services, Inc. Top agencies HHS (Department of Health and Human Services) EEOC (Equal Employment Opportunity Commission)	$266,738,917	0.3%	Rank history: #55 in FY2022, #63 in FY2023 and not on the FY2024–FY2025 lists; down 2 since FY2020.
45	Microsoft Corporation 3 awardees, including Github Inc. Top agencies Army (Department of the Army) Navy (Department of the Navy) USAF (Department of the Air Force)	$265,908,227	0.3%	Rank history: #49 in FY2022, #50 in FY2023, #36 in FY2024 and #39 in FY2025; down 18 since FY2020.
46	Colsa Corp Top agencies USAF (Department of the Air Force) Army (Department of the Army) NASA (National Aeronautics and Space Administration)	$263,534,496	0.3%	Rank history: #90 in FY2022, not on the FY2023 list, #96 in FY2024 and not on the FY2025 list; down 7 since FY2020.
47	International Business Machines Corporation 7 awardees Top agencies DHS (Department of Homeland Security) Army (Department of the Army) VA (Department of Veterans Affairs)	$260,508,903	0.3%	Rank history: #44 in FY2022, #49 in FY2023, #50 in FY2024 and #52 in FY2025; up 12 since FY2020.
48	Arctic Slope Regional Corporation 16 awardees, including Arctic Slope Technical Services, Inc., Asrc Federal System Solutions LLC and Asrc Federal Cyber, LLC Top agencies NASA (National Aeronautics and Space Administration) DOT (Department of Transportation) USAF (Department of the Air Force)	$248,025,924	0.3%	Rank history: #53 in FY2022, #64 in FY2023, #48 in FY2024 and #26 in FY2025; up 18 since FY2020.
49	The Boston Consulting Group Inc 2 awardees, including BCG Federal Corp. Top agencies HHS (Department of Health and Human Services) Navy (Department of the Navy) USAF (Department of the Air Force)	$231,963,006	0.3%	Rank history: #66 in FY2022, #36 in FY2023, #66 in FY2024 and not on the FY2025 list; up 2 since FY2020.
50	Perspecta Inc. 8 awardees, including Peraton Technology Services Inc., Dhpc Technologies, Inc. and Peraton Enterprise Solutions LLC Top agencies Army (Department of the Army) ED (Department of Education) Commerce (Department of Commerce)	$223,107,870	0.3%	Rank history: not on the FY2022–FY2025 lists; down 1 since FY2020.
51	Range Generation Next LLC Top agencies USAF (Department of the Air Force)	$222,303,088	0.3%	Rank history: #61 in FY2022, #51 in FY2023, #63 in FY2024 and not on the FY2025 list; up 17 since FY2020.
52	Mathematica Inc 2 awardees Top agencies HHS (Department of Health and Human Services) ED (Department of Education) DOL (Department of Labor)	$216,956,953	0.3%	Rank history: #56 in FY2022, #66 in FY2023 and not on the FY2024–FY2025 lists; down 11 since FY2020.
53	DCS Corporation 2 awardees Top agencies Army (Department of the Army) USAF (Department of the Air Force) Navy (Department of the Navy)	$213,225,330	0.3%	Rank history: #54 in FY2022, #54 in FY2023, #83 in FY2024 and #92 in FY2025; up 2 since FY2020.
54	Huntington Ingalls Industries, Inc. 7 awardees, including HII Mission Technologies Corp, HII Fleet Support Group LLC and Fulcrum It Services, LLC Top agencies USAF (Department of the Air Force) Navy (Department of the Navy) USSOCOM (United States Special Operations Command)	$211,148,534	0.3%	Rank history: #27 in FY2022, #21 in FY2023, #12 in FY2024 and #14 in FY2025; down 6 since FY2020.
55	H.i.g. Capital Management Inc. 5 awardees, including Iron Bow Technologies, LLC, Empower AI, Inc. and Lionbridge Global Solutions II Inc. Top agencies VA (Department of Veterans Affairs) OSD (Office of the Secretary of Defense) HHS (Department of Health and Human Services)	$207,873,207	0.3%	Rank history: #52 in FY2022, #68 in FY2023 and not on the FY2024–FY2025 lists; up 120 since FY2020.
56	Vera Institute of Justice, Inc. Top agencies HHS (Department of Health and Human Services) DOJ (Department of Justice)	$198,151,979	0.3%	Rank history: #58 in FY2022, #45 in FY2023 and not on the FY2024–FY2025 lists; up 49 since FY2020.
57	Aaski Technology Inc. 5 awardees, including Mag DS Corp and Ausley Associates, Inc. Top agencies Army (Department of the Army) Navy (Department of the Navy) DHS (Department of Homeland Security)	$197,331,869	0.3%	Rank history: #42 in FY2022, #61 in FY2023 and not on the FY2024–FY2025 lists; down 11 since FY2020.
58	Nana Regional Corporation Inc 16 awardees, including Rivertech LLC, Tuvli LLC and Cloud Lake Technology LLC Top agencies DOS (Department of State) DCSA (Defense Counterintelligence and Security Agency) DOJ (Department of Justice)	$191,005,007	0.2%	Rank history: #84 in FY2022 and not on the FY2023–FY2025 lists; up 40 since FY2020.
59	Axient LLC 3 awardees, including Systems Engineering Group, Inc. and Dynamic Concepts LLC Top agencies Army (Department of the Army) USAF (Department of the Air Force) Navy (Department of the Navy)	$189,231,444	0.2%	Rank history: #70 in FY2022 and not on the FY2023–FY2025 lists; down 3 since FY2020.
60	Michael Baker International, LLC 3 awardees, including Sallyport Global Holdings Inc. Top agencies USAF (Department of the Air Force) DOS (Department of State) EPA (Environmental Protection Agency)	$185,106,063	0.2%	Rank history: #43 in FY2022, #40 in FY2023, #51 in FY2024 and not on the FY2025 list; down 30 since FY2020.
61	CGI Technologies and Solutions Inc. 3 awardees, including CGI Federal Inc. Top agencies DOS (Department of State) USAID (US Agency for International Development) DOI (Department of the Interior)	$182,652,774	0.2%	Rank history: #41 in FY2022, #35 in FY2023 and not on the FY2024–FY2025 lists; up 9 since FY2020.
62	Noblis, Inc. 2 awardees, including Noblis MSD LLC Top agencies DOT (Department of Transportation) DHS (Department of Homeland Security) HHS (Department of Health and Human Services)	$180,147,485	0.2%	Rank history: #50 in FY2022, #46 in FY2023, #58 in FY2024 and #63 in FY2025; up 12 since FY2020.
63	Smartronix LLC 2 awardees, including Datastrong, LLC Top agencies Army (Department of the Army) Navy (Department of the Navy) DOJ (Department of Justice)	$176,849,718	0.2%	Rank history: #47 in FY2022, #47 in FY2023 and not on the FY2024–FY2025 lists; down 11 since FY2020.
64	Nippon Telegraph and Telephone Corporation 3 awardees, including NTT Data Federal Services, Inc., NTT Data Services Federal Government, LLC and Docomo Pacific, Inc. Top agencies DOJ (Department of Justice) USAID (US Agency for International Development) Navy (Department of the Navy)	$175,801,517	0.2%	Rank history: #62 in FY2022 and not on the FY2023–FY2025 lists; up 35 since FY2020.
65	HP Enterprise Services LLC 18 awardees, including Peraton Inc., Peraton Government Communications Inc. and Peraton Enterprise Solutions LLC Top agencies DHS (Department of Homeland Security) DOJ (Department of Justice) Navy (Department of the Navy)	$173,673,512	0.2%	Rank history: #23 in FY2022, #22 in FY2023 and not on the FY2024–FY2025 lists; up 27 since FY2020.
66	Sierra Nevada Company, LLC 2 awardees Top agencies USAF (Department of the Air Force) USSOCOM (United States Special Operations Command) WHS (DOD Washington Headquarters Service)	$171,332,424	0.2%	Rank history: not on the FY2022–FY2025 lists; up 30 since FY2020.
67	Cherokee Nation 12 awardees, including Cherokee Nation Strategic Programs, L.L.C., Cherokee Nation Management & Consulting, L.l.c.. and Cherokee Federal Solutions, L.L.C. Top agencies USAF (Department of the Air Force) DHA (Defense Health Agency) Army (Department of the Army)	$169,549,459	0.2%	Rank history: #80 in FY2022, #78 in FY2023 and not on the FY2024–FY2025 lists; down 5 since FY2020.
68	Credence Management Solutions Limited Liability Company Top agencies USAF (Department of the Air Force) USAID (US Agency for International Development) Army (Department of the Army)	$166,792,144	0.2%	Rank history: #57 in FY2022, #52 in FY2023, #49 in FY2024 and #55 in FY2025; down 1 since FY2020.
69	Linquest Corporation 2 awardees, including The Perduco Group, Inc. Top agencies USAF (Department of the Air Force) Navy (Department of the Navy) Army (Department of the Army)	$166,186,347	0.2%	Rank history: #86 in FY2022, #70 in FY2023, #70 in FY2024 and #62 in FY2025; down 5 since FY2020.
70	On Assignment, Inc. 5 awardees, including ECS Federal, LLC, Inforeliance LLC and Indrasoft Inc. Top agencies DOJ (Department of Justice) DARPA (Defense Advanced Research Projects Agency) Commerce (Department of Commerce)	$159,872,641	0.2%	Rank history: #72 in FY2022, #59 in FY2023 and not on the FY2024–FY2025 lists; up 72 since FY2020.
71	Intuitive Research and Technology Corporation 2 awardees Top agencies Army (Department of the Army) USAF (Department of the Air Force)	$152,824,400	0.2%	Rank history: not on the FY2022–FY2025 lists; up 4 since FY2020.
72	Xator LLC 3 awardees, including TSM LLC and Incadence Strategic Solutions LLC Top agencies DOS (Department of State) HHS (Department of Health and Human Services) USAF (Department of the Air Force)	$152,472,311	0.2%	Rank history: #91 in FY2022 and not on the FY2023–FY2025 lists; up 21 since FY2020.
73	BAE Systems Land & Armaments L.P. 10 awardees, including BAE Systems Information and Electronic Systems Integration Inc. and BAE Systems Technology Solutions & Services Inc. Top agencies USAF (Department of the Air Force) Army (Department of the Army) DOJ (Department of Justice)	$152,304,167	0.2%	Rank history: not on the FY2022–FY2025 lists; new, not ranked in FY2020.
74	ACE Info Solutions LLC 2 awardees, including Dovel Technologies LLC and Guidehouse Digital LLC Top agencies HHS (Department of Health and Human Services) USDA (Department of Agriculture)	$146,036,656	0.2%	Rank history: #85 in FY2022 and not on the FY2023–FY2025 lists; up 86 since FY2020.
75	Cognosante Holdings, LLC 3 awardees, including Cognosante, LLC, Cognosante MVH LLC and Cognosante Cds, LLC Top agencies VA (Department of Veterans Affairs) HHS (Department of Health and Human Services) SSA (Social Security Administration)	$144,630,106	0.2%	Rank history: #69 in FY2022, #87 in FY2023, #90 in FY2024 and not on the FY2025 list; up 151 since FY2020.
76	Sev1Tech, LLC Top agencies Army (Department of the Army) DHS (Department of Homeland Security) USAF (Department of the Air Force)	$144,276,749	0.2%	Rank history: #82 in FY2022, #73 in FY2023, #80 in FY2024 and #57 in FY2025; up 8 since FY2020.
77	Westat, Inc. Top agencies HHS (Department of Health and Human Services) ED (Department of Education) USDA (Department of Agriculture)	$143,651,342	0.2%	Rank history: #60 in FY2022, #77 in FY2023, #54 in FY2024 and not on the FY2025 list; up 6 since FY2020.
78	Georgia TECH Research Corp 2 awardees, including Georgia TECH Applied Research Corp Top agencies USAF (Department of the Air Force) DISA (Defense Information Systems Agency) HHS (Department of Health and Human Services)	$142,773,058	0.2%	Rank history: #74 in FY2022, #80 in FY2023 and not on the FY2024–FY2025 lists; up 113 since FY2020.
79	Gryphon Technologies, Inc. 9 awardees, including Gryphon Technologies, L.C., Gryphon Marine, LLC and Schafer Government Services, LLC Top agencies Navy (Department of the Navy) USAF (Department of the Air Force) DARPA (Defense Advanced Research Projects Agency)	$142,408,316	0.2%	Rank history: not on the FY2022 list, #75 in FY2023 and not on the FY2024–FY2025 lists; down 2 since FY2020.
80	Inter-Con Security Systems, Inc. Top agencies DOS (Department of State) DOJ (Department of Justice) USDA (Department of Agriculture)	$140,846,088	0.2%	Rank history: #79 in FY2022, #97 in FY2023 and not on the FY2024–FY2025 lists; up 9 since FY2020.
81	The Day & Zimmermann Group, Inc. Through SOC LLC Top agencies DOS (Department of State)	$136,689,028	0.2%	Rank history: #81 in FY2022 and not on the FY2023–FY2025 lists; down 20 since FY2020.
82	LS Technologies LLC Top agencies DOT (Department of Transportation)	$133,966,842	0.2%	Rank history: #83 in FY2022, #92 in FY2023 and not on the FY2024–FY2025 lists; up 12 since FY2020.
83	Signature Choice, LLC Top agencies VA (Department of Veterans Affairs)	$132,070,820	0.2%	Rank history: not on the FY2022 list, #88 in FY2023 and not on the FY2024–FY2025 lists; up 46 since FY2020.
84	Koniag, Inc. 10 awardees, including Tuknik Government Services LLC, Eagle Harbor Solutions LLC and Pacarctic, LLC Top agencies DISA (Defense Information Systems Agency) USDA (Department of Agriculture) DOS (Department of State)	$131,409,599	0.2%	Rank history: #63 in FY2022, #58 in FY2023 and not on the FY2024–FY2025 lists; up 28 since FY2020.
85	Leonardo S.p.A. 12 awardees, including DRS Network & Imaging Systems LLC, DRS Sustainment Systems, Inc. and DRS Advanced ISR LLC Top agencies Army (Department of the Army) Navy (Department of the Navy) USAF (Department of the Air Force)	$131,346,173	0.2%	Rank history: #88 in FY2022, #41 in FY2023, #57 in FY2024 and #31 in FY2025; down 3 since FY2020.
86	Oasis Systems, LLC Top agencies USAF (Department of the Air Force) DOT (Department of Transportation) Navy (Department of the Navy)	$126,457,232	0.2%	Rank history: #48 in FY2022, #62 in FY2023, #60 in FY2024 and #53 in FY2025; up 40 since FY2020.
87	Grant Thornton International Ltd 2 awardees, including Grant Thornton LLP and Grant Thornton Public Sector LLC Top agencies DOS (Department of State) DHS (Department of Homeland Security) Commerce (Department of Commerce)	$125,472,686	0.2%	Rank history: #71 in FY2022 and not on the FY2023–FY2025 lists; up 79 since FY2020.
88	Triple Canopy Inc. 5 awardees, including Centerra Group, LLC, Academi Training Center LLC and Omniplex World Services Corporation Top agencies DOS (Department of State) Commerce (Department of Commerce) DOJ (Department of Justice)	$123,959,786	0.2%	Rank history: #65 in FY2022 and not on the FY2023–FY2025 lists; up 33 since FY2020.
89	Advanced Technology Systems Inc. 6 awardees, including Salient Crgt, Inc. and Salient Federal-Sgis Inc. Top agencies USAF (Department of the Air Force) PBGC (Pension Benefit Guaranty Corporation) USAID (US Agency for International Development)	$123,820,916	0.2%	Rank history: not on the FY2022 list, #72 in FY2023 and not on the FY2024–FY2025 lists; up 1 since FY2020.
90	UnitedHealth Group Incorporated 7 awardees, including The Lewin Group, Inc., Optumhealth Care Solutions, LLC and Optumserve Technology Services, Inc. Top agencies HHS (Department of Health and Human Services) DHA (Defense Health Agency) VA (Department of Veterans Affairs)	$121,145,590	0.2%	Rank history: #75 in FY2022, not on the FY2023 list, #44 in FY2024 and #38 in FY2025; down 30 since FY2020.
91	Science Systems and Applications, Inc. Top agencies NASA (National Aeronautics and Space Administration) USDA (Department of Agriculture)	$120,677,208	0.2%	Rank history: #93 in FY2022 and not on the FY2023–FY2025 lists; down 3 since FY2020.
92	Ernst & Young LLP 2 awardees Top agencies Army (Department of the Army) HHS (Department of Health and Human Services) DOJ (Department of Justice)	$118,647,462	0.2%	Rank history: not on the FY2022–FY2025 lists; down 11 since FY2020.
93	Systems Planning and Analysis, Inc. Top agencies Navy (Department of the Navy) OSD (Office of the Secretary of Defense) DTRA (Defense Threat Reduction Agency)	$116,405,493	0.1%	Rank history: #78 in FY2022, #60 in FY2023, #53 in FY2024 and #42 in FY2025; up 58 since FY2020.
94	National Exchange Carrier Association Inc. Through Universal Service Administrative Company Top agencies FCC (Federal Communications Commission)	$114,185,000	0.1%	Rank history: not on the FY2022 list, #69 in FY2023 and not on the FY2024–FY2025 lists; new, not ranked in FY2020.
95	B.i. Incorporated Top agencies DHS (Department of Homeland Security)	$114,083,727	0.1%	Rank history: not on the FY2022–FY2025 lists; up 143 since FY2020.
96	Kpmg L.L.P. 2 awardees Top agencies HHS (Department of Health and Human Services) DCSA (Defense Counterintelligence and Security Agency) USAF (Department of the Air Force)	$110,196,092	0.1%	Rank history: #76 in FY2022, #71 in FY2023 and not on the FY2024–FY2025 lists; up 68 since FY2020.
97	American Systems Corporation 3 awardees, including DDL Omni Engineering LLC Top agencies Navy (Department of the Navy) USAF (Department of the Air Force) DHS (Department of Homeland Security)	$109,154,203	0.1%	Rank history: not on the FY2022–FY2025 lists; down 18 since FY2020.
98	Afognak Native Corporation 16 awardees, including Alutiiq Essential Services LLC, Alutiiq Information Management, LLC and Alutiiq Advanced Security Solutions LLC Top agencies DOS (Department of State) NASA (National Aeronautics and Space Administration) USAF (Department of the Air Force)	$108,366,000	0.1%	Rank history: #94 in FY2022 and not on the FY2023–FY2025 lists; up 70 since FY2020.
99	National Opinion Research Center Top agencies HHS (Department of Health and Human Services) CNCS (Corporation for National and Community Service) SEC (Securities and Exchange Commission)	$107,356,731	0.1%	Rank history: #89 in FY2022, #81 in FY2023 and not on the FY2024–FY2025 lists; up 17 since FY2020.
100	Sapient Corporation 3 awardees, including Plowshare Group, Inc., Sapient Government Services, Inc. and Onpoint Consulting, Inc. Top agencies HHS (Department of Health and Human Services)	$106,444,792	0.1%	Rank history: #100 in FY2022, #95 in FY2023 and not on the FY2024–FY2025 lists; up 9 since FY2020.

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100 of 13,350 contractors listed here. See the rest on GovTribe.

Rankings for the codes under PSC R4

Code	Net obligations	Largest contractor
R425 Engineering and Technical Services	$28,743,088,117	Chemonics International, Inc.
R499 Other Professional Services	$22,933,503,448	Booz Allen Hamilton Holding Corporation
R408 Program Management/Support Services	$11,581,734,200	Booz Allen Hamilton Holding Corporation
R429 Support – Professional: Emergency Response/Disaster Planning/Preparedness Support	$2,747,394,769	Rapid Deployment Inc.
R426 Communications Services	$1,284,254,618	The Interpublic Group of Companies Inc
R410 Support – Professional: Program Evaluation/Review/Development	$1,199,247,142	Oasis Systems, LLC
R430 Support – Professional: Physical Security and Badging	$1,020,660,161	Aegis Defense Services,
R405 Operations Research and Quantitative Analysis Services	$597,030,709	Leidos Holdings, Inc.
R497 Personal Services Contracts	$526,200,376	Accenture Federal Services LLC
R418 Legal Services	$487,249,365	Vera Institute of Justice, Inc.
R431 Support – Professional: Human Resources	$474,254,044	Accenture Federal Services LLC
R423 Intelligence Services	$298,584,651	CACI International Inc.
R415 Technology Sharing/Utilization Services	$293,415,503	Accenture Federal Services LLC
R424 Expert Witness	$273,253,535	Georgia TECH Research Corp
R412 Simulation	$271,779,049	Northrop Grumman Corporation
R422 Market Research and Public Opinion Services (includes telephone and field interviews, focus testing, and surveys)	$178,936,201	Westat, Inc.
R406 Policy Review/Development Services	$120,276,219	Criterion Systems, L.L.C.
R416 Veterinary/Animal Care Services	$99,991,323	Priority One Services, Inc.
R427 Weather Reporting/Observation Services	$93,272,268	RTX Corporation
R420 Support – Professional: Certifications and Accreditations (Other Than Education or Information Technology C&A)	$79,107,015	Amentum Services, Inc.
R404 Land Surveys, Cadastral Services (non-construction)	$68,092,170	Lumbee Tribe Enterprises LLC
R411 Real Property Appraisals Services (SIC 6531)	$34,828,342	Verdi Consulting Inc.
R401 Personal Care Services (includes such services as barber and beauty shop, shoe repairs, tailoring, etc.)	$33,564,764	Dependable Health Services, Inc.
R413 Specifications Development Services	$31,702,032	Tetra Tech, Inc.
R428 Industrial Hygienics	$24,488,557	Socha, LLC
R498 Patent and Trademark Services	$10,374,332	The Boeing Company
R402 Real Estate Brokerage Services	-$89,065,936	Mortgage Contracting Services LLC

Show all 27

How this ranking works

Source: every contract action FPDS records (as published on SAM.gov) in the period, as GovTribe received it.
Amounts are net obligations: what was obligated, less what was deobligated. Shares are of $78.5 billion obligated before deobligations, so they never pass 100%.
Parent companies: each action counts under the ultimate parent its award record names, or under the awardee when it names none, so no dollar counts twice. Parents of the same name (Inc., LLC and the like aside) count as one company, since FPDS records a company's parent under more than one UEI over time. GovTribe corrects a few parents and names by hand; see the corrections.
Fiscal year 2021 ran Oct 1, 2020 – Sep 30, 2021. The Department of Defense reports its contract actions to FPDS about 90 days late, so a fiscal year is ranked once they're in, in February, and the list doesn't change after.
Rank changes compare with FY2020. "New" marks a company outside that period's top 500, and "Returned" one of those that was on an earlier fiscal year's list.
Rank lines show each company's rank on every fiscal year's list since FY2021, #1 at the top, on a scale that gives the top of the list more room. A dashed stretch spans years it wasn't on the list. The step from FY2020 takes the color of the rank change beside it.
Placeholder recipients FPDS uses when it names no company ("Miscellaneous Foreign Contractors" and the like) aren't ranked.

Quick answers

Who were the top 10 PSC R4 contractors in FY2021?

1. Booz Allen Hamilton Holding Corporation ($2.68B), 2. The Boeing Company ($2.05B), 3. RTX Corporation ($1.65B), 4. Chemonics International, Inc. ($1.58B), 5. General Dynamics Corporation ($1.55B), 6. Deloitte LLP ($1.42B), 7. Science Applications International Corporation ($1.33B), 8. Northrop Grumman Corporation ($1.31B), 9. Leidos Holdings, Inc. ($1.29B), 10. Rapid Deployment Inc. ($1.28B).

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