The companies listed in Fairfax are primarily mid-sized firms specializing in IT services and defense manufacturing, with a strong focus on government contracts. Many of them offer advanced technology and digital solutions. For example, ECS provides cybersecurity solutions, GovCIO delivers IT solutions for government operations, and MAG Aerospace offers situational awareness solutions for global safety. General Dynamics Advanced Information Systems focuses on mission solutions for defense and intelligence.
A notable pattern among these companies is their significant involvement in serving government clients. Companies like ASM Research and Salient CRGT are dedicated providers of IT consulting and technology solutions for the federal government. This indicates a strong concentration of businesses catering to public sector needs in the Fairfax area.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 |
ECSecstech.com
ECS provides advanced technology, science, and digital solutions to address cyber threats for customers in the public and private sectors |
3,996 | |||
| 2 |
GovCIOgovcio.com
Deliver IT solutions and services using Agile methods and innovation to optimize government operations and support citizen-focused missions. |
3,164 | |||
| 3 |
MAG Aerospacemagaero.com
Provider of real-time situational awareness solutions enabling global safety, delivering C5ISR services, joint domain command, and premier engineering & operational solutions worldwide Website: wwwmagaerocom |
1,928 | |||
| 4 |
General Dynamics Advanced Information Systemsgd-ais.com
An advanced information systems provider offering mission solutions for defense, intelligence, space, and homeland security, integrating land, air, sea, space, and cyber assets |
1,840 | |||
| 5 |
3Pillar3pillarglobal.com
Innovative product development partner driving rapid revenue and growth for industry leaders through lean, agile digital solutions across various technologies |
1,709 | |||
| 6 |
ASM Researchasmr.com
A provider of technology solutions for the Federal government with expertise in IT, program management, security, healthcare, education, and training |
1,678 | |||
| 7 |
Riverside Researchriversideresearch.org
A nonprofit organization conducting independent research in various scientific fields to advance innovation and provide high-value solutions to government customers |
801 | |||
| 8 |
Salient CRGTgovcio.com
Providing comprehensive government IT consulting and management services focused on mission success, innovation, and long-term client partnerships. |
790 | |||
| 9 |
IonIdeaionidea.com
A technology and business process solutions company focused on delivering excellent products, innovative technologies, and high-quality services through passionate professionals and best practices |
783 | |||
| 10 |
All Native Group, The Federal Services Division of Ho-Chunk Inc.allnativegroup.com
A government services provider offering training, health services, IT/telecommunications, staffing, professional services, and program management with key certifications |
445 | |||
| 11 |
UCSucs-inc.com
A rapidly growing government contractor providing Enterprise IT Solutions and Health Services to improve performance across all levels of government |
432 | |||
| 12 |
ITC Federalitcfederal.com
This company is a federal systems integrator focusing on technical and business solutions through innovative practices and skilled professionals |
421 | |||
| 13 |
ControlCasecontrolcase.com
IT compliance company providing peace of mind through proactive, innovative solutions, automation, and comprehensive services for various regulatory requirements in on-premise and cloud environments |
392 | |||
| 14 |
CC Paceccpace.com
A business & IT consulting firm in Fairfax, Virginia offering Business & Data Consulting, Digital Services, Agile Transformation, and technology staffing solutions nationwide |
371 | |||
| 15 |
INTEGRITYOne Partnersionep.com
A business and technology services company specializing in helping Federal Government organizations address challenges and implement effective solutions |
359 | |||
Want more companies than this list?This page shows the largest ones only. Connect to Tamtam to see every company that matches, filter by size, industry or growth, and reach their decision-makers. | |||||
| 16 |
Zimmerman Associates, Inc.zai-inc.com
A Records and Information Management company in Fairfax, VA providing program management and engineering services to DoD entities, certified in ISO standards and CMMI Level 3 |
315 | |||
| 17 | 183 | ||||
| 18 |
Hadiamondstar Software Solutions LLChadiamondstar.com
A global IT services company specializing in consulting and implementing solutions to help businesses re-engineer and compete successfully in the marketplace |
104 | |||
| 19 |
Quantriumquantrium.ai
An IT company specializing in AI, ML, Cloud, and Edge technologies, helping businesses improve efficiency and customer experience through practical applications |
97 | |||
| 20 |
Riverside Technology, inc.css-inc.com
Provides innovative IT solutions for environmental decision support systems, using various environmental data sources for informed stakeholder decisions. |
70 | |||
| 21 |
Reinventing Geospatial, Inc. (RGi)rgi-corp.com
C5ISR innovator and geospatial expert in National Security. Immediate impact for soldiers and analysts through empowered, innovative critical thinkers. |
51 | |||
| 22 |
USmax Corporationusmax.com
A leading IT services firm specializing in Cyber Security, Infrastructure Management, and Enterprise Applications for government, commercial, and non-profit organizations |
33 | |||
| 23 |
Elite Systems Inc.elitesystems.com
The company specializes in systems integration, cloud migration, software development, network and applications security, cyber security, RF benchmarking, wireless optimization, and IT staffing |
28 | |||
| 24 |
Intellisoft Technologiesintellisoft-tech.com
A leading provider of diverse IT solutions for Federal and Commercial sectors, offering consulting, training, software products, and outsourcing services |
18 | |||
| 25 |
Cogentcogent.partners
A global leader in AI and Data Engineering outsourcing, specializing in implementing AI solutions for enterprises and startups to drive business impact |
17 | |||
| 26 |
Tiber Solutions LLCtibersolutions.com
A consultancy specializing in Data Warehousing and Analytics, helping government and commercial clients make better decisions through data-driven solutions |
16 | |||
| 27 |
Rotunda Solutionsrotundasolutions.com
A SDVOSB specializing in data analytics and data science consulting for federal and commercial clients |
15 | |||
| 28 |
Advance Digital Systemsadvancedigitalsys.com
Provider of IT and consulting services for federal and commercial clients, offering a broad range of projects and services across various technologies |
14 | |||
| 29 |
Adaptalytics, LLCadaptalytics.com
A leading data analytic consulting firm specializing in using data, technology, scientific methods, and creativity to solve complex business problems |
13 | |||
| 30 |
NumInformatics Inc.numinformatics.com
Consulting firm specializing in data analytics, machine learning, and AI technologies with experienced data scientists and consultants serving private, public, and government sectors |
8 | |||
Turn this list into pipeline
Tamtam finds the decision-makers at every company on a list like this one, with verified emails, phone numbers and the buying signals that tell you when to reach out.
How this list is built
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 11, 2026.
More company lists in Fairfax
- The largest companies in Fairfax 139
- IT Services and IT Consulting companies in Fairfax 36
- Professional services firms in Fairfax 30
The same list elsewhere in United States
- IT services companies in the United States 5,818
- IT services companies in California 796
- IT services companies in Texas 729
- IT services companies in New York State 468
- IT services companies in Virginia 455
- IT services companies in New Jersey 399
- IT services companies in Florida 321
- IT services companies in Illinois 274
- IT services companies in Georgia 237
- IT services companies in Maryland 179
- IT services companies in Pennsylvania 157
- IT services companies in Massachusetts 155
- IT services companies in Washington State 145
- IT services companies in Ohio 118
- IT services companies in Michigan 114
- IT services companies in North Carolina 96
- IT services companies in Delaware 93
- IT services companies in Alabama 90
- IT services companies in New York 331
- IT services companies in Houston 121
- IT services companies in Chicago 114
- IT services companies in Austin 93
- IT services companies in Atlanta 91
- IT services companies in Miami 88