Top 100 Contractors in PSC Z1: Maintenance, Alteration, Repair Buildings, FY2025

Name: Top 100 Contractors in PSC Z1: Maintenance, Alteration, Repair Buildings, FY2025
Creator: GovTribe

Parent companies by net contract obligations Oct 1, 2024 – Sep 30, 2025 Code page on GovTribe

The top 10 won 24% of FY2025 PSC Z1 contract dollars

Contract obligations: $7,285,193,922 Net of deobligations, by contracts coded PSC Z1 or a code under it
Contractors: 3,315 Parent companies with an obligation
Largest contractor: Amentum Holdings, Inc. $731 million, 9.2% 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	Amentum Holdings, Inc. 8 awardees, including Central Plateau Cleanup Company, LLC, Amentum Technology, Inc. and Amentum Services, Inc. Top agencies DOE (Department of Energy) NASA (National Aeronautics and Space Administration) Navy (Department of the Navy)	$731,324,141	9.2%	Rank history: not on the FY2021–FY2023 lists and #20 in FY2024; up 19 since FY2024.
2	Great Lakes Dredge & Dock Corporation Top agencies Army (Department of the Army)	$266,555,309	3.4%	Rank history: #28 in FY2021, #4 in FY2022, #5 in FY2023 and #1 in FY2024; down 1 since FY2024.
3	J & J Maintenance Inc. Top agencies Army (Department of the Army) DHA (Defense Health Agency) DECA (Defense Commissary Agency)	$215,721,569	2.7%	Rank history: #3 in FY2021, #2 in FY2022, #3 in FY2023 and #3 in FY2024; unchanged since FY2024.
4	Arctic Slope Regional Corporation 9 awardees, including Asrc Federal Facilities Logistics LLC, Netcentric Technology, LLC and Asrc Federal Cyber, LLC Top agencies NASA (National Aeronautics and Space Administration) USAF (Department of the Air Force) MDA (DOD Missile Defense Agency)	$136,481,148	1.7%	Rank history: #12 in FY2021, #20 in FY2022, #33 in FY2023 and #7 in FY2024; up 3 since FY2024.
5	General Dynamics Corporation 4 awardees, including General Dynamics Land Systems Inc. and General Dynamics Mission Systems, Inc. Top agencies Army (Department of the Army) DHS (Department of Homeland Security)	$129,793,782	1.6%	Rank history: #16 in FY2021, #5 in FY2022, #12 in FY2023 and #5 in FY2024; unchanged since FY2024.
6	Curtin Maritime Corp Top agencies Army (Department of the Army) Navy (Department of the Navy)	$103,333,811	1.3%	Rank history: not on the FY2021 list, #41 in FY2022, #23 in FY2023 and #64 in FY2024; up 58 since FY2024.
7	Peter Kiewit Sons', Inc. 2 awardees, including Weeks Marine, Inc. and Kiewit Infrastructure South Co Top agencies Army (Department of the Army)	$88,942,634	1.1%	Rank history: not on the FY2021–FY2022 lists, #45 in FY2023 and #4 in FY2024; down 3 since FY2024.
8	Jones Lang Lasalle Americas, Inc. Top agencies GSA (General Services Administration) DECA (Defense Commissary Agency) Treasury (Department of the Treasury)	$75,679,823	1.0%	Rank history: not on the FY2021–FY2023 lists and #8 in FY2024; unchanged since FY2024.
9	Action Facilities Management Inc. Top agencies GSA (General Services Administration) DOJ (Department of Justice) Army (Department of the Army)	$69,981,575	0.9%	Rank history: #46 in FY2021, #44 in FY2022, #21 in FY2023 and #14 in FY2024; up 5 since FY2024.
10	Norfolk Dredging Company Top agencies Army (Department of the Army)	$68,311,711	0.9%	Rank history: #9 in FY2021, #12 in FY2022, #7 in FY2023 and #63 in FY2024; up 53 since FY2024.
11	Nana Regional Corporation Inc. 5 awardees, including Akima Range Readiness Operations LLC and Sava Workforce Solutions LLC Top agencies USAF (Department of the Air Force) DOJ (Department of Justice)	$65,089,500	0.8%	Rank history: not on the FY2021–FY2022 lists, #43 in FY2023 and #16 in FY2024; up 5 since FY2024.
12	Facility Services Management, Inc. 2 awardees Top agencies Army (Department of the Army) Navy (Department of the Navy) DHA (Defense Health Agency)	$64,821,729	0.8%	Rank history: #24 in FY2021, #21 in FY2022, #6 in FY2023 and #6 in FY2024; down 6 since FY2024.
13	Cashman Dredging & Marine Contracting Co LLC Top agencies Army (Department of the Army)	$64,371,175	0.8%	Rank history: not on the FY2021–FY2024 lists; new.
14	Nelson Refrigeration Inc. Top agencies DECA (Defense Commissary Agency)	$62,873,207	0.8%	Rank history: not on the FY2021–FY2023 lists and #25 in FY2024; up 11 since FY2024.
15	Donjon Marine Co., LLC Top agencies Army (Department of the Army)	$61,776,670	0.8%	Rank history: not on the FY2021–FY2024 lists; new.
16	Pond Constructors Inc. Top agencies DLA (Defense Logistics Agency)	$59,278,745	0.7%	Rank history: #60 in FY2021, #22 in FY2022, #17 in FY2023 and #10 in FY2024; down 6 since FY2024.
17	Professional Contract Services, Inc. Top agencies Navy (Department of the Navy) Army (Department of the Army) DHS (Department of Homeland Security)	$56,939,672	0.7%	Rank history: #17 in FY2021, #14 in FY2022, #20 in FY2023 and #15 in FY2024; down 2 since FY2024.
18	Fluor Corporation Through Fluor Intercontinental, Inc. Top agencies USAF (Department of the Air Force)	$56,100,000	0.7%	Rank history: not on the FY2021–FY2023 lists and #19 in FY2024; up 1 since FY2024.
19	Pegasus Support Services LLC Top agencies Army (Department of the Army) DHS (Department of Homeland Security) GSA (General Services Administration)	$53,512,289	0.7%	Rank history: not on the FY2021–FY2024 lists; up 129 since FY2024.
20	Cottrell Contracting Corporation Top agencies Army (Department of the Army)	$53,312,374	0.7%	Rank history: #66 in FY2021, not on the FY2022 list, #93 in FY2023 and #24 in FY2024; up 4 since FY2024.
21	Akima Facilities Operations LLC Top agencies Army (Department of the Army) DOE (Department of Energy)	$52,602,154	0.7%	Rank history: not on the FY2021–FY2023 lists and #36 in FY2024; up 15 since FY2024.
22	South Dade Air Conditioning & Refrigeration Inc. Top agencies GSA (General Services Administration) AOUSC (Administrative Office of the U.S. Courts) DHS (Department of Homeland Security)	$52,547,799	0.7%	Rank history: not on the FY2021 list, #64 in FY2022, #40 in FY2023 and #28 in FY2024; up 6 since FY2024.
23	Weston Solutions Holdings, Inc. 4 awardees, including Weston Solutions, Inc. Top agencies DLA (Defense Logistics Agency) Army (Department of the Army)	$51,854,154	0.7%	Rank history: #10 in FY2021, #11 in FY2022, #10 in FY2023 and #11 in FY2024; down 12 since FY2024.
24	Tatitlek Corporation Through Tatitlek Technologies, LLC Top agencies DOS (Department of State)	$49,751,585	0.6%	Rank history: not on the FY2021–FY2022 lists, #39 in FY2023 and #18 in FY2024; down 6 since FY2024.
25	Emcor Group Inc. Through Emcor Government Services, Inc. Top agencies GSA (General Services Administration) GAO (Government Accountability Office) HHS (Department of Health and Human Services)	$49,432,511	0.6%	Rank history: #5 in FY2021, #8 in FY2022, #13 in FY2023 and #22 in FY2024; down 3 since FY2024.
26	Bridger Richard JV LLC Top agencies VA (Department of Veterans Affairs)	$47,279,808	0.6%	Rank history: not on the FY2021–FY2024 lists; new.
27	Amerifield JV LLC Top agencies VA (Department of Veterans Affairs)	$45,603,496	0.6%	Rank history: not on the FY2021–FY2024 lists; new.
28	Saw Greenland, LLC Top agencies VA (Department of Veterans Affairs)	$41,222,156	0.5%	Rank history: not on the FY2021–FY2024 lists; new.
29	Serviam Construction LLC Top agencies VA (Department of Veterans Affairs)	$39,965,513	0.5%	Rank history: not on the FY2021–FY2023 lists and #33 in FY2024; up 4 since FY2024.
30	The Dutra Group Top agencies Army (Department of the Army)	$39,713,703	0.5%	Rank history: #7 in FY2021, not on the FY2022 list, #31 in FY2023 and #87 in FY2024; up 57 since FY2024.
31	Bristol Bay Native Corporation 5 awardees, including SES Construction and Fuel Services LLC, Specpro Environmental Services LLC and CCI Facility Support Services, LLC Top agencies Army (Department of the Army) DLA (Defense Logistics Agency) Navy (Department of the Navy)	$39,117,720	0.5%	Rank history: #64 in FY2021, #62 in FY2022, #75 in FY2023 and #47 in FY2024; up 16 since FY2024.
32	J&J and Alms Mission Support Solutions, LLC Top agencies Navy (Department of the Navy) USAF (Department of the Air Force) DHA (Defense Health Agency)	$38,417,411	0.5%	Rank history: not on the FY2021–FY2023 lists and #96 in FY2024; up 64 since FY2024.
33	Global Pacific Design Builders, LLC Top agencies Navy (Department of the Navy)	$38,311,584	0.5%	Rank history: not on the FY2021 list, #51 in FY2022, #16 in FY2023 and #52 in FY2024; up 19 since FY2024.
34	V2X, Inc. Through V2X Systems LLC Top agencies Navy (Department of the Navy) Army (Department of the Army)	$37,930,803	0.5%	Rank history: not on the FY2021–FY2024 lists; up 88 since FY2024.
35	King & George, LLC Top agencies Army (Department of the Army) GSA (General Services Administration) Navy (Department of the Navy)	$36,265,968	0.5%	Rank history: #48 in FY2021, #37 in FY2022, #64 in FY2023 and #54 in FY2024; up 19 since FY2024.
36	Jll-Midnight Sun Ifms LLC Top agencies Navy (Department of the Navy) DHA (Defense Health Agency) Army (Department of the Army)	$34,351,346	0.4%	Rank history: #35 in FY2021, #31 in FY2022, #48 in FY2023 and #39 in FY2024; up 3 since FY2024.
37	Hospital Housekeeping Systems LLC Top agencies Army (Department of the Army)	$33,149,964	0.4%	Rank history: not on the FY2021–FY2024 lists; new.
38	Birmingham Industrial Construction, LLC Top agencies VA (Department of Veterans Affairs) USAF (Department of the Air Force)	$32,744,579	0.4%	Rank history: not on the FY2021–FY2023 lists and #86 in FY2024; up 48 since FY2024.
39	Valiant Integrated Services LLC 2 awardees, including Valiant Government Services LLC and Valiant / Alca JV LLC Top agencies DHA (Defense Health Agency) Army (Department of the Army) Navy (Department of the Navy)	$32,037,340	0.4%	Rank history: not on the FY2021–FY2022 lists, #34 in FY2023 and #30 in FY2024; down 9 since FY2024.
40	Volmar Construction Inc. Top agencies DOJ (Department of Justice)	$30,980,980	0.4%	Rank history: not on the FY2021–FY2024 lists; new.
41	Mike Hooks, LLC Top agencies Army (Department of the Army)	$29,909,338	0.4%	Rank history: not on the FY2021–FY2024 lists; up 344 since FY2024.
42	Lockheed Martin Corporation Top agencies USAF (Department of the Air Force)	$28,611,699	0.4%	Rank history: not on the FY2021–FY2024 lists; new.
43	Tetra TECH Inc. Top agencies DLA (Defense Logistics Agency)	$28,599,169	0.4%	Rank history: not on the FY2021 list, #46 in FY2022, #47 in FY2023 and #13 in FY2024; down 30 since FY2024.
44	Semper TEK Inc Top agencies VA (Department of Veterans Affairs) Army (Department of the Army)	$27,449,401	0.3%	Rank history: not on the FY2021–FY2022 lists, #85 in FY2023 and not on the FY2024 list; up 73 since FY2024.
45	Koman Construction, LLC Top agencies DHS (Department of Homeland Security) Navy (Department of the Navy)	$27,073,498	0.3%	Rank history: not on the FY2021 list, #95 in FY2022, not on the FY2023 list and #85 in FY2024; up 40 since FY2024.
46	Southwind Construction Corp. Top agencies Army (Department of the Army)	$26,357,504	0.3%	Rank history: not on the FY2021–FY2024 lists; new.
47	K'oyitl'ots'ina, Limited 2 awardees, including Yukon Fire Protection Services, Inc. and Kcorp Technology Services, Inc. Top agencies GSA (General Services Administration) AOUSC (Administrative Office of the U.S. Courts) DOJ (Department of Justice)	$25,113,533	0.3%	Rank history: not on the FY2021–FY2024 lists; up 185 since FY2024.
48	Manson Construction Co Top agencies Army (Department of the Army)	$24,990,609	0.3%	Rank history: #25 in FY2021, #26 in FY2022, #37 in FY2023 and #35 in FY2024; down 13 since FY2024.
49	M.c. Dean, Inc. Top agencies GSA (General Services Administration) HHS (Department of Health and Human Services) DISA (Defense Information Systems Agency)	$24,373,013	0.3%	Rank history: not on the FY2021 list, #75 in FY2022 and not on the FY2023–FY2024 lists; up 57 since FY2024.
50	Pundir Group, Inc. Top agencies GSA (General Services Administration) AOUSC (Administrative Office of the U.S. Courts) DCMA (Defense Contract Management Agency)	$24,045,448	0.3%	Rank history: not on the FY2021–FY2023 lists and #74 in FY2024; up 24 since FY2024.
51	Mckenzie Construction & Site Development LLC Top agencies DOI (Department of the Interior) DOT (Department of Transportation) USDA (Department of Agriculture)	$23,743,528	0.3%	Rank history: not on the FY2021–FY2024 lists; up 409 since FY2024.
52	Elektro-Krueck-Gmbh, Elektroinstallationen Top agencies Army (Department of the Army)	$23,594,331	0.3%	Rank history: #83 in FY2021, not on the FY2022–FY2023 lists and #83 in FY2024; up 31 since FY2024.
53	V Line Services L.L.C. Top agencies VA (Department of Veterans Affairs)	$23,087,400	0.3%	Rank history: not on the FY2021–FY2024 lists; new.
54	Cdeem Co Top agencies VA (Department of Veterans Affairs)	$22,900,000	0.3%	Rank history: not on the FY2021–FY2024 lists; new.
55	Fedcap Rehabilitation Services, Inc. Top agencies GSA (General Services Administration) AOUSC (Administrative Office of the U.S. Courts) DHS (Department of Homeland Security)	$21,803,979	0.3%	Rank history: not on the FY2021–FY2022 lists, #73 in FY2023 and #98 in FY2024; up 43 since FY2024.
56	Sergents Mechanical Systems Inc. Top agencies VA (Department of Veterans Affairs) DHS (Department of Homeland Security) DOT (Department of Transportation)	$21,473,279	0.3%	Rank history: #78 in FY2021 and not on the FY2022–FY2024 lists; up 117 since FY2024.
57	Ohishi Construction Co. Ltd Top agencies Navy (Department of the Navy)	$21,445,766	0.3%	Rank history: not on the FY2021–FY2024 lists; new.
58	LB & B Associates Inc. Top agencies GSA (General Services Administration) AOUSC (Administrative Office of the U.S. Courts) Commerce (Department of Commerce)	$21,244,402	0.3%	Rank history: not on the FY2021 list, #77 in FY2022, #99 in FY2023 and #78 in FY2024; up 20 since FY2024.
59	Nippo Corporation Top agencies Army (Department of the Army) USAF (Department of the Air Force)	$20,031,093	0.3%	Rank history: not on the FY2021–FY2024 lists; up 225 since FY2024.
60	Guidehouse Inc. Through Aptim Federal Services, LLC Top agencies DLA (Defense Logistics Agency)	$19,360,018	0.2%	Rank history: not on the FY2021–FY2023 lists and #9 in FY2024; down 51 since FY2024.
61	Northern Management Services, Inc. Top agencies GSA (General Services Administration) DOI (Department of the Interior) DOL (Department of Labor)	$19,143,772	0.2%	Rank history: not on the FY2021 list, #83 in FY2022, #60 in FY2023 and #69 in FY2024; up 8 since FY2024.
62	Electronic Metrology Laboratory, LLC Top agencies GSA (General Services Administration) Treasury (Department of the Treasury) AOUSC (Administrative Office of the U.S. Courts)	$18,871,837	0.2%	Rank history: not on the FY2021–FY2023 lists and #100 in FY2024; up 38 since FY2024.
63	Marinex Construction Inc. Top agencies Army (Department of the Army)	$18,722,579	0.2%	Rank history: #44 in FY2021, #29 in FY2022, #14 in FY2023 and #40 in FY2024; down 23 since FY2024.
64	Tactical Infrastructure Maintenance Solutions LLC Top agencies DHS (Department of Homeland Security)	$18,578,521	0.2%	Rank history: #59 in FY2021, #70 in FY2022, #94 in FY2023 and #76 in FY2024; up 12 since FY2024.
65	Skookum Educational Programs Top agencies DHS (Department of Homeland Security) Army (Department of the Army) Navy (Department of the Navy)	$18,549,056	0.2%	Rank history: #21 in FY2021, #23 in FY2022, #18 in FY2023 and #42 in FY2024; down 23 since FY2024.
66	Kekolu Contracting, LLC Top agencies Navy (Department of the Navy) OSD (Office of the Secretary of Defense) USAF (Department of the Air Force)	$18,511,381	0.2%	Rank history: not on the FY2021–FY2024 lists; up 268 since FY2024.
67	American Engineering Corporation Top agencies Navy (Department of the Navy) DODEA (Department of Defense Education Activity) DLA (Defense Logistics Agency)	$18,429,105	0.2%	Rank history: not on the FY2021–FY2023 lists and #70 in FY2024; up 3 since FY2024.
68	Nve, Inc. Top agencies Treasury (Department of the Treasury) USDA (Department of Agriculture) USAF (Department of the Air Force)	$18,282,018	0.2%	Rank history: not on the FY2021–FY2023 lists and #65 in FY2024; down 3 since FY2024.
69	Ameritech Contracting LLC Top agencies VA (Department of Veterans Affairs)	$18,240,903	0.2%	Rank history: not on the FY2021–FY2024 lists; up 60 since FY2024.
70	U.s. Vet General Contracting, LLC Top agencies VA (Department of Veterans Affairs)	$18,173,949	0.2%	Rank history: not on the FY2021–FY2022 lists, #69 in FY2023 and not on the FY2024 list; returned.
71	T&H Services, LLC Top agencies DOS (Department of State) Navy (Department of the Navy) USAF (Department of the Air Force)	$18,111,987	0.2%	Rank history: not on the FY2021–FY2024 lists; up 40 since FY2024.
72	Roselin Charitar Top agencies Army (Department of the Army)	$17,501,692	0.2%	Rank history: not on the FY2021–FY2024 lists; new.
73	Fdcd II Joint Venture, LLC Top agencies VA (Department of Veterans Affairs)	$16,539,000	0.2%	Rank history: not on the FY2021–FY2024 lists; new.
74	Tehama, LLC Top agencies USAF (Department of the Air Force)	$16,311,903	0.2%	Rank history: not on the FY2021–FY2024 lists; up 132 since FY2024.
75	KTH Services JV, LLC Top agencies Navy (Department of the Navy) DHS (Department of Homeland Security) USAF (Department of the Air Force)	$16,293,005	0.2%	Rank history: not on the FY2021–FY2024 lists; new.
76	Pacarctic, LLC Top agencies DOS (Department of State) GSA (General Services Administration) DOI (Department of the Interior)	$16,270,938	0.2%	Rank history: not on the FY2021–FY2024 lists; up 71 since FY2024.
77	Daniels Building Co Inc. Top agencies VA (Department of Veterans Affairs)	$16,134,023	0.2%	Rank history: #84 in FY2021, #94 in FY2022 and not on the FY2023–FY2024 lists; up 154 since FY2024.
78	SKE Technical Services GMBH Top agencies DODEA (Department of Defense Education Activity) DECA (Defense Commissary Agency)	$15,589,349	0.2%	Rank history: not on the FY2021–FY2024 lists; up 110 since FY2024.
79	RBA Engineering International, PLLC Top agencies DOI (Department of the Interior)	$15,539,702	0.2%	Rank history: not on the FY2021–FY2024 lists; new.
80	Amvet Ritz JV LLC Top agencies VA (Department of Veterans Affairs)	$15,375,000	0.2%	Rank history: not on the FY2021–FY2024 lists; new.
81	CAS FSE JV II LLC Top agencies HHS (Department of Health and Human Services) USDA (Department of Agriculture) DLA (Defense Logistics Agency)	$15,165,629	0.2%	Rank history: not on the FY2021–FY2024 lists; up 209 since FY2024.
82	Eastman Aggregate Enterprises LLC Top agencies Army (Department of the Army)	$14,974,541	0.2%	Rank history: not on the FY2021–FY2024 lists; new.
83	Coactint LLC Top agencies VA (Department of Veterans Affairs)	$14,828,672	0.2%	Rank history: not on the FY2021–FY2024 lists; new.
84	Occi Inc Top agencies Army (Department of the Army)	$14,773,000	0.2%	Rank history: not on the FY2021–FY2024 lists; new.
85	Integriward LLC Top agencies DHS (Department of Homeland Security) Army (Department of the Army) EPA (Environmental Protection Agency)	$14,769,022	0.2%	Rank history: not on the FY2021–FY2024 lists; up 40 since FY2024.
86	Sori E&C Co.,Ltd Top agencies Army (Department of the Army)	$14,746,677	0.2%	Rank history: not on the FY2021–FY2024 lists; up 53 since FY2024.
87	The Building People LLC Top agencies DOI (Department of the Interior) GSA (General Services Administration) DHS (Department of Homeland Security)	$14,577,056	0.2%	Rank history: not on the FY2021–FY2024 lists; up 15 since FY2024.
88	Global Systemized Industry Top agencies USAF (Department of the Air Force) Army (Department of the Army)	$14,552,123	0.2%	Rank history: not on the FY2021–FY2024 lists; up 156 since FY2024.
89	Dean / Fluor, LLC Top agencies DOJ (Department of Justice)	$14,438,393	0.2%	Rank history: not on the FY2021–FY2024 lists; up 146 since FY2024.
90	Teamgov, Inc. Top agencies Army (Department of the Army) GSA (General Services Administration) HHS (Department of Health and Human Services)	$14,286,073	0.2%	Rank history: not on the FY2021–FY2024 lists; up 290 since FY2024.
91	The Matthews Group Inc. Top agencies DOT (Department of Transportation)	$14,120,332	0.2%	Rank history: not on the FY2021–FY2022 lists, #96 in FY2023 and not on the FY2024 list; returned.
92	Modern International Inc. Top agencies USAF (Department of the Air Force) Navy (Department of the Navy)	$13,923,767	0.2%	Rank history: not on the FY2021–FY2024 lists; new.
93	Cavu Consulting LLC Top agencies VA (Department of Veterans Affairs)	$13,918,839	0.2%	Rank history: not on the FY2021–FY2024 lists; new.
94	DB Netz AG Regionalnetz Oberpfalz Top agencies Army (Department of the Army)	$13,727,901	0.2%	Rank history: not on the FY2021 list, #57 in FY2022, #55 in FY2023 and #61 in FY2024; down 33 since FY2024.
95	Belt Built Contracting, LLC Top agencies Navy (Department of the Navy) Commerce (Department of Commerce) Smithsonian (Smithsonian Institution)	$13,715,071	0.2%	Rank history: not on the FY2021–FY2024 lists; up 260 since FY2024.
96	Welch Construction Inc. Top agencies VA (Department of Veterans Affairs)	$13,675,680	0.2%	Rank history: #71 in FY2021, #36 in FY2022, #97 in FY2023 and not on the FY2024 list; up 63 since FY2024.
97	Dubois Construction, Inc. Top agencies HHS (Department of Health and Human Services)	$13,449,319	0.2%	Rank history: not on the FY2021–FY2024 lists; new.
98	Government Contracting Resources, Inc. Top agencies Navy (Department of the Navy) USAF (Department of the Air Force) DLA (Defense Logistics Agency)	$13,392,639	0.2%	Rank history: not on the FY2021–FY2023 lists and #95 in FY2024; down 3 since FY2024.
99	Modesto Management LLC Top agencies VA (Department of Veterans Affairs)	$13,317,152	0.2%	Rank history: not on the FY2021–FY2024 lists; new.
100	DAE Sung LLC Top agencies GSA (General Services Administration) SSA (Social Security Administration) AOUSC (Administrative Office of the U.S. Courts)	$13,274,981	0.2%	Rank history: not on the FY2021–FY2023 lists and #99 in FY2024; down 1 since FY2024.

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100 of 3,315 contractors listed here. See the rest on GovTribe.

Rankings for the codes under PSC Z1

Code	Net obligations	Largest contractor
Z1AA Maintenance of Office Buildings	$1,164,441,357	Action Facilities Management Inc.
Z1DA Maintenance of Hospitals and Infirmaries	$1,038,957,192	J & J Maintenance Inc.
Z1KF Maintenance of Dredging Facilities	$814,872,369	Great Lakes Dredge & Dock Corporation
Z1JZ Maintenance of Miscellaneous Buildings	$750,767,655	Amentum Holdings, Inc.
Z1PD Maintenance of Waste Treatment and Storage Facilities	$573,137,532	Amentum Holdings, Inc.
Z1AZ Maintenance of Other Administrative Facilities and Service Buildings	$481,711,376	Arctic Slope Regional Corporation
Z1PZ Maintenance of Other Non-Building Facilities	$308,908,892	Amentum Holdings, Inc.
Z1LB Maintenance of Highways/Roads/Streets/Bridges/Railways	$247,115,311	Koman Construction, LLC
Z1NA Maintenance of Fuel Supply Facilities	$188,967,909	Pond Constructors Inc.
Z1HB Maintenance of Government-Owned Government-Operated (Gogo) R&D Facilities	$161,748,239	Arctic Slope Regional Corporation
Z1KB Maintenance of Canals	$152,918,364	Great Lakes Dredge & Dock Corporation
Z1BD Maintenance of Airport Runways and Taxiways	$135,961,359	Fluor Corporation
Z1DZ Maintenance of Other Hospital Buildings	$110,837,218	Sergents Mechanical Systems Inc.
Z1FA Maintenance of Family Housing Facilities	$106,319,060	Global Pacific Design Builders, LLC
Z1QA Maintenance of Restoration of Real Property (Public or Private)	$94,946,328	Nana Regional Corporation Inc.
Z1NB Maintenance of Heating and Cooling Plants	$81,770,547	Saw Greenland, LLC
Z1BC Maintenance of Radar and Navigational Facilities	$69,523,631	Lockheed Martin Corporation
Z1FC Maintenance of Troop Housing Facilities	$62,695,296	Nippo Corporation
Z1KA Maintenance of Dams	$60,497,113	Occi Inc
Z1DB Maintenance of Laboratories and Clinics	$54,119,489	Valiant Integrated Services LLC
Z1BA Maintenance of Air Traffic Control Towers	$53,824,080	The Matthews Group Inc.
Z1EB Maintenance of Maintenance Buildings	$50,697,158	Enviremedial Services, Inc.
Z1CA Maintenance of Schools	$49,734,310	SKE Technical Services GMBH
Z1NZ Maintenance of Other Utilities	$38,056,643	Advanced Management Group L.L.C.
Z1EZ Maintenance of Other Industrial Buildings	$33,713,616	Gracen Engineering & Construction Inc.
Z1NE Maintenance of Water Supply Facilities	$33,652,359	Mountain Point, LLC
Z1ND Maintenance of Sewage and Waste Facilities	$29,374,030	Fedvet Construction
Z1BG Maintenance of Electronic and Communications Facilities	$25,446,845	Northrop Grumman Corporation
Z1PA Maintenance of Recreation Facilities (Non-Building)	$19,558,237	K.w. Emerson, Inc.
Z1JA Maintenance of Museums and Exhibition Buildings	$18,544,616	Constructora Rogers, S.A. (Conrosa)
Z1GZ Maintenance of Other Warehouse Buildings	$16,915,358	Integriward LLC
Z1LZ Maintenance of Parking Facilities	$14,016,007	Construction Partners, Inc.
Z1FB Maintenance of Recreational Buildings	$13,589,402	Kyunan Co., Ltd.
Z1BZ Maintenance of Other Airfield Structures	$10,884,650	Mckenzie Construction & Site Development LLC
Z1FD Maintenance of Dining Facilities	$3,887,534	American Engineering Corporation
Z1FZ Maintenance of Other Residential Buildings	-$5,406,125	Parliament LLC

Show all 36

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 $7.93 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 2025 ran Oct 1, 2024 – Sep 30, 2025. 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 FY2024. "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 FY2024 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 Z1 contractors in FY2025?

1. Amentum Holdings, Inc. ($731M), 2. Great Lakes Dredge & Dock Corporation ($267M), 3. J & J Maintenance Inc. ($216M), 4. Arctic Slope Regional Corporation ($136M), 5. General Dynamics Corporation ($130M), 6. Curtin Maritime Corp ($103M), 7. Peter Kiewit Sons', Inc. ($88.9M), 8. Jones Lang Lasalle Americas, Inc. ($75.7M), 9. Action Facilities Management Inc. ($70M), 10. Norfolk Dredging Company ($68.3M).

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