Top 100 Environmental Protection Agency Contractors, FY2023

Full ranking

Rank	Contractor	Net obligations	Share	Trend
1	General Dynamics Corporation 3 awardees, including General Dynamics Information Technology, Inc. Top NAICS codes 541512 Computer Systems Design Services 541611 Administrative Management and General Management Consulting Services 541519 Other Computer Related Services	$146,260,627	6.1%	Rank history: #1 in FY2021, #3 in FY2022, #2 in FY2024 and #2 in FY2025; up 2 since FY2022.
2	Tetra Tech, Inc. 11 awardees Top NAICS codes 541620 Environmental Consulting Services 562910 Remediation Services 541715 Research and Development in the Physical, Engineering, and Life Sciences (except Nanotechnology and Biotechnology)	$110,311,078	4.6%	Rank history: #4 in FY2021, #4 in FY2022, #5 in FY2024 and #9 in FY2025; up 2 since FY2022.
3	EA Engineering, Science, and Technology, Inc., PBC Top NAICS codes 562910 Remediation Services 541715 Research and Development in the Physical, Engineering, and Life Sciences (except Nanotechnology and Biotechnology)	$109,436,948	4.5%	Rank history: #5 in FY2021, #1 in FY2022, #3 in FY2024 and #7 in FY2025; down 2 since FY2022.
4	AECOM 2 awardees, including AECOM Technical Services, Inc. and URS Group, Inc. Top NAICS codes 562910 Remediation Services 541330 Engineering Services	$106,904,762	4.4%	Rank history: #23 in FY2021, #11 in FY2022, #78 in FY2024 and #84 in FY2025; up 7 since FY2022.
5	Environmental Restoration LLC Top NAICS codes 562910 Remediation Services	$100,327,372	4.2%	Rank history: #2 in FY2021, #2 in FY2022, #9 in FY2024 and #4 in FY2025; down 3 since FY2022.
6	Jacobs Engineering Group Inc. 5 awardees, including Ch2M Hill, Inc. and Amentum Technology, Inc. Top NAICS codes 562910 Remediation Services 541715 Research and Development in the Physical, Engineering, and Life Sciences (except Nanotechnology and Biotechnology) 541330 Engineering Services	$90,958,975	3.8%	Rank history: #6 in FY2021, #14 in FY2022, #74 in FY2024 and not on the FY2025 list; up 8 since FY2022.
7	Eastern Research Group Inc. Top NAICS codes 541620 Environmental Consulting Services 541990 All Other Professional, Scientific, and Technical Services 541380 Testing Laboratories and Services	$83,049,535	3.4%	Rank history: #7 in FY2021, #6 in FY2022, #4 in FY2024 and #8 in FY2025; down 1 since FY2022.
8	Arctic Slope Regional Corporation 5 awardees, including Environmental Quality Management, Inc., EQM Services, LLC and Asrc Federal Data Network Technologies, LLC Top NAICS codes 562910 Remediation Services 541512 Computer Systems Design Services	$67,953,104	2.8%	Rank history: #12 in FY2021, #44 in FY2022, #36 in FY2024 and #3 in FY2025; up 36 since FY2022.
9	Hydrogeologic, Inc. Top NAICS codes 562910 Remediation Services	$63,660,585	2.6%	Rank history: #15 in FY2021, #15 in FY2022, #6 in FY2024 and #11 in FY2025; up 6 since FY2022.
10	ICF International, Inc. Through ICF Incorporated, L.L.C. Top NAICS codes 541611 Administrative Management and General Management Consulting Services 541620 Environmental Consulting Services 541990 All Other Professional, Scientific, and Technical Services	$60,006,496	2.5%	Rank history: #9 in FY2021, #10 in FY2022, #24 in FY2024 and not on the FY2025 list; unchanged since FY2022.
11	CDM Smith Inc Through CDM Federal Programs Corporation Top NAICS codes 562910 Remediation Services	$57,803,122	2.4%	Rank history: not on the FY2021–FY2022 lists, #59 in FY2024 and not on the FY2025 list; new.
12	Advanced Technology Systems Inc. Through Salient Crgt, Inc. Top NAICS codes 541512 Computer Systems Design Services	$52,000,000	2.2%	Rank history: not on the FY2021 list, #24 in FY2022, #17 in FY2024 and not on the FY2025 list; up 12 since FY2022.
13	C M C, Inc. Top NAICS codes 562910 Remediation Services	$42,663,299	1.8%	Rank history: #32 in FY2021, #16 in FY2022, #23 in FY2024 and #51 in FY2025; up 3 since FY2022.
14	CGI Technologies and Solutions Inc. Through CGI Federal Inc. Top NAICS codes 541512 Computer Systems Design Services 518210 Computing Infrastructure Providers, Data Processing, Web Hosting, and Related Services 541519 Other Computer Related Services	$40,423,140	1.7%	Rank history: #8 in FY2021, #8 in FY2022, #25 in FY2024 and not on the FY2025 list; down 6 since FY2022.
15	Kemron / Arrowhead JV, LLC Top NAICS codes 562910 Remediation Services	$39,785,837	1.6%	Rank history: #41 in FY2021, #21 in FY2022 and not on the FY2024–FY2025 lists; up 6 since FY2022.
16	Research Triangle Institute Top NAICS codes 541611 Administrative Management and General Management Consulting Services 541620 Environmental Consulting Services 541715 Research and Development in the Physical, Engineering, and Life Sciences (except Nanotechnology and Biotechnology)	$32,824,805	1.4%	Rank history: #18 in FY2021, #20 in FY2022, #18 in FY2024 and #20 in FY2025; up 4 since FY2022.
17	Cape Remediation, LLC Top NAICS codes 562910 Remediation Services	$30,500,000	1.3%	Rank history: not on the FY2021–FY2022 lists, #53 in FY2024 and #49 in FY2025; new.
18	Weston Solutions Holdings, Inc. 3 awardees, including Weston Solutions Inc. Top NAICS codes 541620 Environmental Consulting Services	$27,740,515	1.1%	Rank history: #20 in FY2021, #12 in FY2022, #19 in FY2024 and #5 in FY2025; down 6 since FY2022.
19	Sevenson Environmental Services, Inc. Top NAICS codes 562910 Remediation Services	$25,848,567	1.1%	Rank history: #14 in FY2021, #13 in FY2022, #1 in FY2024 and #1 in FY2025; down 6 since FY2022.
20	Arrowhead Contracting, LLC Top NAICS codes 562910 Remediation Services	$25,843,246	1.1%	Rank history: not on the FY2021–FY2022 lists, #76 in FY2024 and #25 in FY2025; new.
21	Kemron Environmental Services, Inc. Top NAICS codes 562910 Remediation Services	$23,330,360	1.0%	Rank history: #16 in FY2021, #18 in FY2022 and not on the FY2024–FY2025 lists; down 3 since FY2022.
22	Aptim Federal Services LLC 2 awardees Top NAICS codes 562910 Remediation Services 541715 Research and Development in the Physical, Engineering, and Life Sciences (except Nanotechnology and Biotechnology) 541380 Testing Laboratories and Services	$23,164,402	1.0%	Rank history: #25 in FY2021, #22 in FY2022 and not on the FY2024–FY2025 lists; unchanged since FY2022.
23	Agile Decision Sciences, LLC Top NAICS codes 541990 All Other Professional, Scientific, and Technical Services	$21,126,571	0.9%	Rank history: not on the FY2021–FY2022 lists, #35 in FY2024 and not on the FY2025 list; new.
24	Booz Allen Hamilton Holding Corporation Through Booz Allen Hamilton Inc. Top NAICS codes 541512 Computer Systems Design Services 561621 Security Systems Services (except Locksmiths) 541511 Custom Computer Programming Services	$20,283,195	0.8%	Rank history: #17 in FY2021, #23 in FY2022, #28 in FY2024 and #28 in FY2025; down 1 since FY2022.
25	Dell Federal Systems L.P. Top NAICS codes 511210 Software Publishers 541519 Other Computer Related Services 334112 Computer Storage Device Manufacturing	$18,632,363	0.8%	Rank history: #24 in FY2021, #31 in FY2022 and not on the FY2024–FY2025 lists; up 6 since FY2022.
26	Oak Ridge Associated Universities, Incorporated Top NAICS codes 541990 All Other Professional, Scientific, and Technical Services	$17,080,304	0.7%	Rank history: #28 in FY2021, #30 in FY2022, #44 in FY2024 and not on the FY2025 list; up 4 since FY2022.
27	At&T Inc. 4 awardees, including At&T Enterprises, LLC and Att Mobility LLC Top NAICS codes 517110 Wired Telecommunications Carriers 541519 Other Computer Related Services 517810 All Other Telecommunications	$16,978,673	0.7%	Rank history: not on the FY2021 list, #38 in FY2022 and not on the FY2024–FY2025 lists; up 11 since FY2022.
28	The Cadmus Group LLC Top NAICS codes 541620 Environmental Consulting Services 541611 Administrative Management and General Management Consulting Services	$16,177,529	0.7%	Rank history: #34 in FY2021, #32 in FY2022, #12 in FY2024 and #34 in FY2025; up 4 since FY2022.
29	Hdr, Inc. Through HDR Aptim LLC Top NAICS codes 562910 Remediation Services	$15,597,087	0.6%	Rank history: #38 in FY2021, #28 in FY2022, #70 in FY2024 and #40 in FY2025; down 1 since FY2022.
30	Weston-Techlaw JV LLC Top NAICS codes 541620 Environmental Consulting Services	$15,452,244	0.6%	Rank history: not on the FY2021 list, #52 in FY2022, #46 in FY2024 and #36 in FY2025; up 22 since FY2022.
31	Salient Crgt, Inc. Top NAICS codes 541512 Computer Systems Design Services	$14,575,000	0.6%	Rank history: not on the FY2021–FY2022 lists, #13 in FY2024 and #6 in FY2025; new.
32	Datawiz Corporation Top NAICS codes 541519 Other Computer Related Services	$14,566,313	0.6%	Rank history: not on the FY2021–FY2022 lists, #47 in FY2024 and not on the FY2025 list; new.
33	Skeo Solutions, Inc. Top NAICS codes 541620 Environmental Consulting Services	$14,174,969	0.6%	Rank history: #72 in FY2021, #26 in FY2022, #43 in FY2024 and #69 in FY2025; down 7 since FY2022.
34	A and M Engineering & Environmental Services Inc Top NAICS codes 562910 Remediation Services	$13,920,364	0.6%	Rank history: not on the FY2021–FY2022 lists and not on the FY2024–FY2025 lists; new.
35	MCP Computer Products Inc. Top NAICS codes 334111 Electronic Computer Manufacturing	$13,484,152	0.6%	Rank history: #27 in FY2021, #37 in FY2022, #55 in FY2024 and #42 in FY2025; up 2 since FY2022.
36	Firelake-Diversified JV2 LLC Top NAICS codes 236220 Commercial and Institutional Building Construction	$13,200,110	0.5%	Rank history: not on the FY2021–FY2022 lists, #40 in FY2024 and not on the FY2025 list; new.
37	Paragon Professional Services LLC Top NAICS codes 562910 Remediation Services 237990 Other Heavy and Civil Engineering Construction	$13,088,437	0.5%	Rank history: not on the FY2021–FY2022 lists, #48 in FY2024 and #21 in FY2025; new.
38	EQ & CH Remediation Top NAICS codes 562910 Remediation Services	$12,831,525	0.5%	Rank history: #30 in FY2021, #39 in FY2022, #22 in FY2024 and not on the FY2025 list; up 1 since FY2022.
39	General Dynamics Information Technology, Inc. Top NAICS codes 541512 Computer Systems Design Services 541620 Environmental Consulting Services 541519 Other Computer Related Services	$12,300,856	0.5%	Rank history: not on the FY2021 list, #25 in FY2022 and not on the FY2024–FY2025 lists; down 14 since FY2022.
40	ABT Global LLC 2 awardees Top NAICS codes 541611 Administrative Management and General Management Consulting Services 541620 Environmental Consulting Services	$11,864,159	0.5%	Rank history: #39 in FY2021, #42 in FY2022 and not on the FY2024–FY2025 lists; up 2 since FY2022.
41	Wood Environment & Infrastructure Solutions Inc. Through WSP USA Environment & Infrastructure Inc. Top NAICS codes 541620 Environmental Consulting Services 561210 Facilities Support Services 541380 Testing Laboratories and Services	$11,081,084	0.5%	Rank history: #26 in FY2021, #78 in FY2022, #68 in FY2024 and not on the FY2025 list; up 37 since FY2022.
42	Toeroek Associates, Inc. Top NAICS codes 541620 Environmental Consulting Services 562910 Remediation Services	$10,740,395	0.4%	Rank history: #59 in FY2021, #41 in FY2022, #88 in FY2024 and #72 in FY2025; down 1 since FY2022.
43	Patriot LLC Top NAICS codes 541512 Computer Systems Design Services	$10,082,150	0.4%	Rank history: #36 in FY2021, #29 in FY2022, #54 in FY2024 and #94 in FY2025; down 14 since FY2022.
44	Noresco, LLC Top NAICS codes 541330 Engineering Services	$10,057,588	0.4%	Rank history: not on the FY2021–FY2022 lists, not on the FY2024 list and #79 in FY2025; new.
45	Leisnoi Diversified Services, LLC Top NAICS codes 562910 Remediation Services	$9,996,821	0.4%	Rank history: #35 in FY2021, #35 in FY2022, #41 in FY2024 and #43 in FY2025; down 10 since FY2022.
46	RTX Corporation Through Noresco, LLC Top NAICS codes 541330 Engineering Services	$9,971,206	0.4%	Rank history: not on the FY2021–FY2022 lists and not on the FY2024–FY2025 lists; new.
47	Great Lakes Environmental Center, Inc. Top NAICS codes 541620 Environmental Consulting Services	$9,925,934	0.4%	Rank history: #70 in FY2021, #48 in FY2022, #58 in FY2024 and #64 in FY2025; up 1 since FY2022.
48	Techlaw, Inc. Through Techlaw Consultants Inc. Top NAICS codes 562910 Remediation Services 541380 Testing Laboratories and Services	$9,924,229	0.4%	Rank history: #46 in FY2021, #43 in FY2022 and not on the FY2024–FY2025 lists; down 5 since FY2022.
49	Systalex Corporation Top NAICS codes 541519 Other Computer Related Services	$9,634,961	0.4%	Rank history: #43 in FY2021, #49 in FY2022, #42 in FY2024 and #41 in FY2025; unchanged since FY2022.
50	Camp Dresser & Mckee Inc. 4 awardees, including CDM Federal Programs Corporation Top NAICS codes 541330 Engineering Services	$9,585,774	0.4%	Rank history: #10 in FY2021, #9 in FY2022 and not on the FY2024–FY2025 lists; down 41 since FY2022.
51	SRC Inc. Top NAICS codes 541620 Environmental Consulting Services 541715 Research and Development in the Physical, Engineering, and Life Sciences (except Nanotechnology and Biotechnology)	$9,004,307	0.4%	Rank history: #37 in FY2021, #46 in FY2022, #61 in FY2024 and #76 in FY2025; down 5 since FY2022.
52	Versar-Envirocon JV Top NAICS codes 562910 Remediation Services	$8,510,801	0.4%	Rank history: not on the FY2021 list, #98 in FY2022, not on the FY2024 list and #93 in FY2025; up 46 since FY2022.
53	Maximus Inc. Through Maximus Federal Technology Solutions, LLC Top NAICS codes 541512 Computer Systems Design Services 541511 Custom Computer Programming Services	$8,076,712	0.3%	Rank history: not on the FY2021 list, #50 in FY2022 and not on the FY2024–FY2025 lists; down 3 since FY2022.
54	CDM Federal Programs Corporation Top NAICS codes 562910 Remediation Services	$7,560,635	0.3%	Rank history: not on the FY2021–FY2022 lists, #14 in FY2024 and #12 in FY2025; up 275 since FY2022.
55	Pegasus Technical Services, Inc. Top NAICS codes 541715 Research and Development in the Physical, Engineering, and Life Sciences (except Nanotechnology and Biotechnology) 541712 Research and Development in the Physical, Engineering, and Life Sciences (except Biotechnology)	$7,499,430	0.3%	Rank history: #45 in FY2021, #57 in FY2022, #65 in FY2024 and #60 in FY2025; up 2 since FY2022.
56	The Health Effects Institute Top NAICS codes 541715 Research and Development in the Physical, Engineering, and Life Sciences (except Nanotechnology and Biotechnology)	$7,498,511	0.3%	Rank history: not on the FY2021–FY2022 lists and not on the FY2024–FY2025 lists; new.
57	Noreas Aptim Environmental Remediation JV Top NAICS codes 562910 Remediation Services	$7,004,748	0.3%	Rank history: not on the FY2021–FY2022 lists and not on the FY2024–FY2025 lists; new.
58	Science Applications International Corporation Top NAICS codes 541620 Environmental Consulting Services 541512 Computer Systems Design Services	$6,854,578	0.3%	Rank history: #3 in FY2021, #7 in FY2022, #32 in FY2024 and #32 in FY2025; down 51 since FY2022.
59	Leidos Holdings, Inc. 6 awardees, including Leidos Management Systems Designers, Inc. and Leidos, Inc. Top NAICS codes 443120 Computer and Software Stores 541512 Computer Systems Design Services 541511 Custom Computer Programming Services	$6,790,399	0.3%	Rank history: #61 in FY2021, #72 in FY2022 and not on the FY2024–FY2025 lists; up 13 since FY2022.
60	Chenega It Enterprise Services, LLC Top NAICS codes 518210 Computing Infrastructure Providers, Data Processing, Web Hosting, and Related Services	$6,666,635	0.3%	Rank history: #22 in FY2021, #51 in FY2022, #52 in FY2024 and #35 in FY2025; down 9 since FY2022.
61	Consolidated Safety Services Incorporated Top NAICS codes 541380 Testing Laboratories and Services 541715 Research and Development in the Physical, Engineering, and Life Sciences (except Nanotechnology and Biotechnology) 541620 Environmental Consulting Services	$6,616,889	0.3%	Rank history: #53 in FY2021, #65 in FY2022, #95 in FY2024 and #45 in FY2025; up 4 since FY2022.
62	Pb&A / CSS JV, Llc. Top NAICS codes 541620 Environmental Consulting Services	$6,587,932	0.3%	Rank history: not on the FY2021 list, #55 in FY2022 and not on the FY2024–FY2025 lists; down 7 since FY2022.
63	Battelle Memorial Institute Top NAICS codes 541715 Research and Development in the Physical, Engineering, and Life Sciences (except Nanotechnology and Biotechnology) 541620 Environmental Consulting Services 541611 Administrative Management and General Management Consulting Services	$6,537,920	0.3%	Rank history: #44 in FY2021, #56 in FY2022, #63 in FY2024 and #78 in FY2025; down 7 since FY2022.
64	Lintech Global Inc Top NAICS codes 541511 Custom Computer Programming Services 541512 Computer Systems Design Services	$6,432,801	0.3%	Rank history: not on the FY2021–FY2022 lists, not on the FY2024 list and #70 in FY2025; new.
65	Oneida Nation 2 awardees, including OCH JV Top NAICS codes 562910 Remediation Services	$6,334,619	0.3%	Rank history: not on the FY2021–FY2022 lists and not on the FY2024–FY2025 lists; up 57 since FY2022.
66	Gartner, Inc. Top NAICS codes 541690 Other Scientific and Technical Consulting Services 541620 Environmental Consulting Services 541519 Other Computer Related Services	$5,982,956	0.2%	Rank history: #98 in FY2021, #95 in FY2022 and not on the FY2024–FY2025 lists; up 29 since FY2022.
67	S C & A Inc. 2 awardees Top NAICS codes 541620 Environmental Consulting Services	$5,973,747	0.2%	Rank history: #75 in FY2021, #85 in FY2022, #20 in FY2024 and #15 in FY2025; up 18 since FY2022.
68	Arcadis N.V. Through Arcadis U.s., Inc. Top NAICS codes 541330 Engineering Services	$5,860,076	0.2%	Rank history: #49 in FY2021, #36 in FY2022 and not on the FY2024–FY2025 lists; down 32 since FY2022.
69	M.c. Dean, Inc. Top NAICS codes 541330 Engineering Services	$5,830,740	0.2%	Rank history: #50 in FY2021, #64 in FY2022, #57 in FY2024 and #63 in FY2025; down 5 since FY2022.
70	WSP USA Solutions Inc. Top NAICS codes 541330 Engineering Services	$5,265,908	0.2%	Rank history: not on the FY2021 list, #34 in FY2022, #92 in FY2024 and not on the FY2025 list; down 36 since FY2022.
71	Specpro-Ayuda JV, LLC Top NAICS codes 562910 Remediation Services	$5,248,028	0.2%	Rank history: not on the FY2021–FY2022 lists, #77 in FY2024 and not on the FY2025 list; new.
72	State of California Controllers Office 2 awardees, including University of California, Davis and University of California, San Diego Top NAICS codes 541380 Testing Laboratories and Services 813920 Professional Organizations 541990 All Other Professional, Scientific, and Technical Services	$5,226,993	0.2%	Rank history: #82 in FY2021, not on the FY2022 list and not on the FY2024–FY2025 lists; up 29 since FY2022.
73	Information International Associates Inc. 2 awardees, including Keylogic, LLC and Keylogic Associates, Inc. Top NAICS codes 541511 Custom Computer Programming Services 541519 Other Computer Related Services	$5,107,388	0.2%	Rank history: #78 in FY2021, #87 in FY2022 and not on the FY2024–FY2025 lists; up 14 since FY2022.
74	Veracity Consulting, Inc. Top NAICS codes 541519 Other Computer Related Services	$5,037,560	0.2%	Rank history: #68 in FY2021, #62 in FY2022, not on the FY2024 list and #73 in FY2025; down 12 since FY2022.
75	Otie-Pwt JV, LLC Top NAICS codes 562910 Remediation Services	$4,800,193	0.2%	Rank history: not on the FY2021 list, #67 in FY2022 and not on the FY2024–FY2025 lists; down 8 since FY2022.
76	Industrial Economics Inc. Top NAICS codes 541611 Administrative Management and General Management Consulting Services 541620 Environmental Consulting Services	$4,765,516	0.2%	Rank history: #65 in FY2021, #54 in FY2022 and not on the FY2024–FY2025 lists; down 22 since FY2022.
77	Better By Design LLC Top NAICS codes 562910 Remediation Services	$4,613,576	0.2%	Rank history: not on the FY2021–FY2022 lists and not on the FY2024–FY2025 lists; new.
78	J.f. Brennan Company, Inc. Top NAICS codes 562910 Remediation Services	$4,461,526	0.2%	Rank history: not on the FY2021 list, #5 in FY2022, #26 in FY2024 and #85 in FY2025; down 73 since FY2022.
79	Comptech Computer Technologies, Inc. Top NAICS codes 541519 Other Computer Related Services	$4,340,837	0.2%	Rank history: #84 in FY2021, not on the FY2022 list, #73 in FY2024 and #62 in FY2025; up 27 since FY2022.
80	Mythics, LLC Through Emergent, LLC Top NAICS codes 541519 Other Computer Related Services	$4,225,982	0.2%	Rank history: not on the FY2021–FY2022 lists and not on the FY2024–FY2025 lists; new.
81	Cetacean Marine Inc. Top NAICS codes 483114 Coastal and Great Lakes Passenger Transportation	$4,151,257	0.2%	Rank history: not on the FY2021 list, #89 in FY2022 and not on the FY2024–FY2025 lists; up 8 since FY2022.
82	MPF Federal, LLC Top NAICS codes 541940 Veterinary Services 541990 All Other Professional, Scientific, and Technical Services	$3,996,032	0.2%	Rank history: #80 in FY2021, #73 in FY2022, #96 in FY2024 and not on the FY2025 list; down 9 since FY2022.
83	Data Systems Analysts Inc. Through Project Performance Company, LLC Top NAICS codes 541519 Other Computer Related Services	$3,898,000	0.2%	Rank history: #77 in FY2021, #58 in FY2022, #62 in FY2024 and #75 in FY2025; down 25 since FY2022.
84	Diversified Protection Corp Top NAICS codes 561612 Security Guards and Patrol Services	$3,820,777	0.2%	Rank history: #60 in FY2021, #75 in FY2022, #91 in FY2024 and #86 in FY2025; down 9 since FY2022.
85	Kgsne JV II LLC Top NAICS codes 562910 Remediation Services	$3,786,791	0.2%	Rank history: not on the FY2021 list, #69 in FY2022, not on the FY2024 list and #61 in FY2025; down 16 since FY2022.
86	Horsley Witten Group, Inc. Top NAICS codes 541620 Environmental Consulting Services	$3,777,348	0.2%	Rank history: #56 in FY2021, #100 in FY2022, #84 in FY2024 and not on the FY2025 list; up 14 since FY2022.
87	ST George Tanaq Corp Through Heliotech Top NAICS codes 562910 Remediation Services	$3,776,550	0.2%	Rank history: #93 in FY2021, not on the FY2022 list and not on the FY2024–FY2025 lists; up 74 since FY2022.
88	Koniag, Inc. Through Arlluk Technology Solutions LLC Top NAICS codes 541511 Custom Computer Programming Services	$3,771,453	0.2%	Rank history: not on the FY2021–FY2022 lists and not on the FY2024–FY2025 lists; new.
89	Savan Group LLC Top NAICS codes 541611 Administrative Management and General Management Consulting Services	$3,762,687	0.2%	Rank history: not on the FY2021–FY2022 lists and not on the FY2024–FY2025 lists; new.
90	Plateau Software, Inc. Top NAICS codes 541513 Computer Facilities Management Services 541511 Custom Computer Programming Services	$3,710,822	0.2%	Rank history: not on the FY2021–FY2022 lists, #82 in FY2024 and not on the FY2025 list; up 34 since FY2022.
91	Arctic Slope Mission Services LLC Top NAICS codes 541990 All Other Professional, Scientific, and Technical Services	$3,652,157	0.2%	Rank history: #13 in FY2021, #19 in FY2022 and not on the FY2024–FY2025 lists; down 72 since FY2022.
92	Environmental Management Support, Inc. Top NAICS codes 541620 Environmental Consulting Services	$3,611,869	0.1%	Rank history: #71 in FY2021, #99 in FY2022, #93 in FY2024 and #68 in FY2025; up 7 since FY2022.
93	Verizon Communications Inc. Through Cellco Partnership Top NAICS codes 541519 Other Computer Related Services 517312 Wireless Telecommunications Carriers (except Satellite)	$3,535,130	0.1%	Rank history: #88 in FY2021, #94 in FY2022 and not on the FY2024–FY2025 lists; up 1 since FY2022.
94	University of North Carolina at Chapel Hill 3 awardees Top NAICS codes 541620 Environmental Consulting Services 519120 Libraries and Archives 541618 Other Management Consulting Services	$3,426,582	0.1%	Rank history: #74 in FY2021, #91 in FY2022 and not on the FY2024–FY2025 lists; down 3 since FY2022.
95	Nobis Engineering, Inc. Top NAICS codes 562910 Remediation Services	$3,401,757	0.1%	Rank history: #31 in FY2021, #33 in FY2022, #34 in FY2024 and not on the FY2025 list; down 62 since FY2022.
96	Duke Energy Corporation Through Duke Energy Progress, LLC Top NAICS codes 221122 Electric Power Distribution	$3,325,000	0.1%	Rank history: #64 in FY2021, #88 in FY2022, #90 in FY2024 and not on the FY2025 list; down 8 since FY2022.
97	Wilson 5 Service Company, Inc. Top NAICS codes 561210 Facilities Support Services	$3,287,112	0.1%	Rank history: not on the FY2021–FY2022 lists, #97 in FY2024 and #90 in FY2025; up 12 since FY2022.
98	Intepros Federal Incorporated Top NAICS codes 541512 Computer Systems Design Services	$3,249,271	0.1%	Rank history: not on the FY2021–FY2022 lists, not on the FY2024 list and #91 in FY2025; up 15 since FY2022.
99	Aleut Technical Services, LLC Top NAICS codes 541620 Environmental Consulting Services	$3,211,133	0.1%	Rank history: not on the FY2021–FY2022 lists, #87 in FY2024 and #98 in FY2025; new.
100	Ch2M Hill, Inc. Top NAICS codes 562910 Remediation Services	$3,124,624	0.1%	Rank history: #62 in FY2021, #17 in FY2022, #11 in FY2024 and #14 in FY2025; down 83 since FY2022.

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 $2.41 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 2023 ran Oct 1, 2022 – Sep 30, 2023. 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 FY2022. "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 FY2022 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