| # | Company | Employees |
|---|---|---|
| 1 | 36,645 | |
| 2 | 10,724 | |
| 3 | 3,124 | |
| 4 |
Bowman Consultingbowman.com
A national engineering services provider delivering infrastructure solutions to customers in various regulated end markets, with expertise in planning, engineering, and environmental consulting |
2,221 |
| 5 |
GuidePoint Securityguidepointsecurity.com
Elite team of certified experts providing holistic cybersecurity solutions, guiding organizations to make informed decisions, choose appropriate products, and optimize resources |
1,364 |
| 6 |
Noblisnoblis.org
A nonprofit organization providing scientific, technology, and strategy services to government and industry clients in national security, healthcare, and environmental sustainability |
1,313 |
| 7 |
Tkxelcareers.tkxel.com
Tkxel is a USA-based software development company providing innovative solutions like AI, IoT, and cybersecurity to help businesses achieve their digital transformation goals globally |
1,264 |
| 8 |
AIS (Applied Information Sciences)ais.com
IT transformation firm specializing in compliant cloud and data solutions for large enterprises, governments, and defense agencies, driving innovation and modernization |
768 |
| 9 |
Systems Engineering Services Corporation (SESC)sesc.com
Provider of technology solutions specializing in program management, application development, systems integration, mobile development, virtualization, and systems security for various industries |
681 |
| 10 |
Brillient Corporationbrillient.net
An award-winning company specializing in full spectrum digital transformation, helping clients achieve efficiencies and lower costs through government and IT modernization initiatives |
556 |
| 11 |
HydroGeoLogic, Inc.hgl.com
Employee-owned company with 36 years of experience providing innovative engineering and remediation solutions to reverse environmental impacts, restore natural resources, and support clients |
458 |
| 12 |
Amyx, Inc.amyx.com
A management and technical solutions provider for Federal Government clients, offering program management, systems engineering, enterprise architecture, and business process transformation services |
437 |
| 13 |
Collaborative Solutions, LLCcollaborativesolutions.com
A global consultancy specializing in Finance and HR Transformation, leveraging cloud solutions to deliver successful outcomes for clients worldwide |
437 |
| 14 |
1Rivet1rivet.com
An award-winning IT Strategy & Consulting firm offering custom Cloud, Application Modernization, and Advanced Analytics solutions to public and private sector clients globally |
405 |
| 15 |
Whitney, Bradley & Brown (WBB)wbbinc.com
A government and public sector solutions provider focused on innovative advances in technology and methodologies to meet client challenges effectively |
324 |
| 16 | 313 | |
| 17 |
GTA (Global Technology Associates) - A Kelly Telecom Companygtatelecom.com
The company provides telecom engineering solutions for legacy, 5G, and private networks through staffing, scope of work, and direct hire services |
282 |
| 18 |
Modus Createmoduscreate.com
Specializing in digital transformation, our global team helps clients innovate and build competitive advantage through strategic consulting, product development, and platform modernization |
270 |
| 19 |
Golden Key Groupgoldenkeygroup.com
A trusted professional services firm assisting federal government with strategic, organizational, and operational challenges in human resources, human capital, learning, and development |
249 |
| 20 |
Pantheon Incpantheon-inc.com
Specializing in products, software development, consulting, and support services, we have centers of excellence focused on various technology solutions Trusted by Fortune 100 companies worldwide |
233 |
| 21 |
Vivid Edge Corpvivid-edge.com
A premier services provider specializing in deploying Oracle applications, Integration technology, MetricStream GRC, Enterprise Data Management, and Predictive Analytics solutions globally |
109 |
| 22 |
Plumlogix (MBE Salesforce Partner)plumlogix.com
A technology-driven Salesforce Service company with a global team of consultants offering tailored solutions for digital transformation and business value |
68 |
| 23 |
BreakForth Solutions, Inc. ED/WOSBbreakforthsolutions.com
Results-focused provider of technical and professional services specializing in Engineering, Data Analytics, IT Business Solutions, and Professional Services for federal agencies and government contractors |
53 |
| 24 |
InfiniSource Consulting Solutions, Inc.icsfederal.com
Leading provider of Management Consulting, Information Technology, and Professional services to federal government, tailored to meet diverse client needs with PMBOK methodology |
46 |
| 25 |
Confianceconfiancegroup.com
Global provider of business transformation solutions for commercial and government organizations through consulting, training, technology, and managed services to achieve efficiency and improved service |
44 |
| 26 |
Centrifuge LLCcentrifugecorp.com
Transforming data into decisions through collaboration, innovative data management, analytics, and business intelligence to save clients time and money globally |
34 |
| 27 |
Johnson Technology Systems, Inc. (JTSi)jtsusa.com
An IT and Engineering Services provider specializing in delivering mission-critical professional IT services, with a focus on SAP/ERP solutions for the Public Sector |
34 |
| 28 |
KYM ADVISORS, INC.kymadvisors.com
Specializes in data sciences, cybersecurity, information sharing, IT modernization, cloud strategy, and agile program delivery for clients. |
26 |
| 29 |
Systems Development and Analysissystemsdev.com
This company focuses on clients' missions, providing independent and innovative technology solutions at the interfaces of IT, business, and operations |
10 |
| 30 |
ERP Doctorserpdoctors.com
A digital transformation consulting firm specializing in ERP systems like Infor CloudSuite, Microsoft Dynamics, Oracle Netsuite, and SAP S/4HANA, with successful implementations in North America |
5 |
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Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Nov 2, 2026.
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