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NAICS 561621

Top contractors in NAICS 561621

The 308 contractors with tracked federal awards in NAICS 561621, totalling $2,637,138,548. Ranked by award value.

See live NAICS 561621 opportunities →All contractors

1M. C. DEAN, INC.$326,942,12887 awards
2GENERAL DYNAMICS MISSION SYSTEMS, INC.$246,227,2514 awards
3SERCO INC$186,491,8844 awards
4FIRST COAST SECURITY SOLUTIONS, INC.$143,383,9838 awards
5CACI INTERNATIONAL INC$132,486,1873 awards
6ADVANCED TECHNOLOGY SYSTEMS COMPANY, INC. (OF VIRGINIA)$118,311,4992 awards
7TRIPLE CANOPY INC$108,593,42120 awards
8JOHNSON CONTROLS SECURITY SOLUTIONS LLC$106,392,69472 awards
9PARAGON SYSTEMS INC$93,286,6234 awards
10XATOR LLC$77,741,1416 awards
11KBR WYLE SERVICES, LLC$71,902,2303 awards
12INDYNE, INC.$62,140,1314 awards
13CHENEGA INTEGRATED SECURITY SOLUTIONS, LLC$55,277,4614 awards
14JOHNSON CONTROLS BUILDING AUTOMATION SYSTEMS, LLC$53,486,8806 awards
15VERSAR SECURITY SYSTEMS, LLC$51,602,64546 awards
16SRCTEC, LLC$32,310,0222 awards
17OLGOONIK SOLUTIONS LLC$27,945,5021 awards
18BIRDI SYSTEMS, INC.$25,220,6353 awards
19GLOBAL RESOURCE SOLUTIONS INC$23,484,6018 awards
20BCF SOLUTIONS, INC.$22,087,4944 awards
21TROFHOLZ TECHNOLOGIES, INC.$21,502,7566 awards
22INDYNE, INC$20,966,4092 awards
23SIEMENS INDUSTRY INC$19,823,67312 awards
24JOHNSON CONTROLS FIRE PROTECTION LP$18,742,26820 awards
25GONZALES CONSULTING SERVICES INC$18,473,0382 awards
26CONCORD CROSSROADS LLC$18,264,4591 awards
27SCDATACOM, LLC$17,859,36613 awards
28ELECTRONIC SYSTEMS SERVICES INC$16,153,1201 awards
29SMITHS DETECTION INC.$15,023,5215 awards
30PARSONS GOVERNMENT SERVICES INC.$14,959,0081 awards
31USMAX CORPORATION$14,240,9291 awards
32CHEROKEE NATION SYSTEM SOLUTIONS LLC$13,605,0605 awards
33HURTVET SUBCONTRACTING, INC.$12,862,31113 awards
34EVERGREEN FIRE ALARMS LLC$12,685,5384 awards
35LOW VOLTAGE WIRING LTD$12,593,3803 awards
36KR CONTRACTING INC$12,034,8271 awards
37LBYD FEDERAL, LLC$11,463,7551 awards
38VETERANS FIRE AND LIFE SAFETY CORPORATION$10,744,32716 awards
39PTSI MANAGED SERVICES INC$10,493,8422 awards
40TRILOGY SECURED SERVICES, L.L.C$10,256,9105 awards
41ELECTRIPRO, INC.$10,210,2733 awards
42MEDIA PLUMBING & HEATING INC$10,049,4099 awards
43SYSTEMS ENGINEERING INC$9,670,6971 awards
44ADVANTOR SYSTEMS II LLC$9,552,5233 awards
45LOCKWOOD HILLS FEDERAL LLC$9,452,1361 awards
46KASTLE SYSTEMS LLC$8,781,65811 awards
47CACI NSS, LLC$8,229,7922 awards
48INTEGRIWARD, LLC$7,817,9213 awards
49THE FIELDS GROUP, LLC$6,803,4233 awards
50SIGNET TECHNOLOGIES, INC.$6,618,6244 awards
51CORELOGIX CONSULTING INC$6,479,2234 awards
52CHENEGA SECURITY INTERNATIONAL, LLC$6,407,0353 awards
53NATIONAL PROJECT MANAGEMENT LLC$5,996,1851 awards
54JOHNSONDANFORTH, INC$5,955,0162 awards
55COMMUNICATIONS RESOURCE INC$5,868,5536 awards
56CHENEGA GLOBAL PROTECTION, LLC$5,658,8851 awards
57PUYENPA SERVICES, LLC$5,417,4771 awards
58RAPISCAN SYSTEMS INC$5,375,6287 awards
59JOHNSON CONTROLS, INC$5,029,3515 awards
60PLANNING, INC.$4,615,4432 awards