Company lists · Data refreshed September 2026
Top 25 Defense cybersecurity companies based in Arlington, United States
RevenueBase identified 58 defense cybersecurity companies headquartered in Arlington, United States as of September 2026 and tracks 1,934 professional contacts across them, including 844 with verified work emails and 952 with mobile numbers. Washington is the largest hub.
This list covers defense cybersecurity companies headquartered in Arlington, United States, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 10, 2026.
Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.
The 25 largest defense cybersecurity companies based in Arlington, United States
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 647 contacts → | ||||
Indirect evidence “At Two Six Technologies, we build, deploy, and implement innovative products that solve the world’s most complex challenges today.” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 2 | 265 contacts → | ||||
Partial evidence “For nearly two decades, Millennium Corporation has been operating on the leading edge of cybersecurity.” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 3 | 237 contacts → | ||||
Indirect evidence “Cydecor advances national security through innovative end-to-end solutions to our customers around the globe.” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 4 | 69 contacts → | ||||
Indirect evidence “Designing Information Security Solutions with YOU in Mind.” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 5 | 60 contacts → | ||||
Indirect evidence “Sancorp Consulting, LLC is focused on providing tailored, professional solutions in the areas of Insider Threat, Artificial Intelligence/Machine Learning, Identity Activities, and…” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 6 | 59 contacts → | ||||
Partial evidence “Tesla Laboratories provides Cyber Security, Intelligence Analysis, Financial Management and Program Management services to the Intelligence Community, the Department of Defense…” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 7 | 58 contacts → | ||||
Partial evidence “CYBASTION develops robust world-class cybersecurity solutions tailored to suit the needs of different businesses, governments and public sector entities.” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 8 | 47 contacts → | ||||
Indirect evidence “System Planning Corporation (SPC)’s success supporting U.S.” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 9 | 41 contacts → | ||||
Indirect evidence “ACI Solutions is a Secure Cloud and Managed Services Provider with U.S headquarters in Arlington, Virginia.” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 10 | 33 contacts → | ||||
Partial evidence “Sun Management is a customer focused cybersecurity & advanced network solutions firm providing products and services that help solve your most difficult IT challenges.” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 11 | 27 contacts → | ||||
Indirect evidence “Big Business Capability from a Small Business HLinc delivers holistic solutions to our customers’ needs – we develop, integrate, and implement technological solutions, customized…” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 12 | 21 contacts → | ||||
Partial evidence “Cybersecurity Research and Development firm” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 13 | 19 contacts → | ||||
Partial evidence “STP is an IT services company that specializes in building mission critical infrastructure, applications and cybersecurity systems.” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 14 | 14 contacts → | ||||
Indirect evidence “CEDELIS is an 8(a) Service-Disabled Minority Veteran-Owned Small Business (SDVOSB) that offers innovative IT services to Federal and Civilian agencies, located in the Washington…” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 15 | 13 contacts → | ||||
Indirect evidence “ExistX was founded in 2023 with the goal to combine cutting edge invention with practical implementation in the unique environments our customers demand to solve national security…” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 16 | 11 contacts → | ||||
Indirect evidence “Hancock & Poole Security (HPS) Inc.” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 17 | 11 contacts → | ||||
Indirect evidence “Dowless & Associates was incorporated in Dowless & Associates' competencies include Information and Cyber Security, IT Integration, Organizational Change Management and Integrated…” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 18 | 10 contacts → | ||||
Indirect evidence “Cynnovative’s mission: To enable our customers to achieve superiority in the cyber domain by rewriting the laws of cyber and advancing state-of-the-art machine learning and…” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 19 | 7 contacts → | ||||
Partial evidence “The Enterprise Security Consultants, LLC (dba TES Consultants) is an 8(a) Woman-Owned Small Business (WOSB) delivering industry leading cybersecurity and information technology…” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 20 | 7 contacts → | ||||
Indirect evidence “Amches provides Wireless and Cyber Security Solutions using proprietary advanced Agile Methodology to cohesively integrate Program Management, Systems Engineering, and both…” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 21 | 6 contacts → | ||||
Partial evidence “Tactibit is a small business serving Federal customers, specializing in Cybersecurity, Cloud Services and IT Operations.” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 22 | 6 contacts → | ||||
Partial evidence “Neuvik is a cybersecurity services company organized into cross-discipline offerings focused on integrating assessments and risk management into comprehensive security solutions.” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 23 | 6 contacts → | ||||
Partial evidence “Cyberblack is an Arlington, Virginia based consulting firm that specializes in providing commercial, government and personal solutions in the cybersecurity field.” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 24 | 4 contacts → | ||||
Partial evidence “Whether it's cybersecurity, cloud computing, data analytics, emerging technologies, or operational guidance, our experts possess the knowledge and skills necessary to deliver…” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
| 25 | 4 contacts → | ||||
Partial evidence “Can your cybersecurity really be the make or break of your company?” Source: RevenueBase Database · checked Sep 10, 2026Thanks. The Data Team will review it. | |||||
RevenueBase Smart Search
RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: defense cybersecurity companies. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.
- Strong evidence
- The company's own public description of its business names defense cybersecurity companies.
- Partial evidence
- Its own public description names part of defense cybersecurity companies, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name defense cybersecurity companies. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.
RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.
Showing 25 of 58 defense cybersecurity companies based in Arlington, United States
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Defense cybersecurity companies based in Arlington, United States at a glance
As of Sep 10, 2026Companies by employee count
Freshness & accuracy
How recently the business emails were verified and the company information checked
Email last verified
Median 13.0dCompany record updated
Median 55.0dHow this list was built
Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among defense cybersecurity companies, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.
- Source
- The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
- What qualifies
- Companies headquartered in Arlington, United States whose own description of what they do matches “defense cybersecurity companies”. Matching reads each company's description, not its industry code or its name.
- RevenueBase Smart Search
- RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names defense cybersecurity companies), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
- What we exclude
- Companies whose own description does not clearly place them among defense cybersecurity companies, and records with no verified work email. Companies headquartered outside Arlington are excluded even when they keep an office there.
- Match quality
- In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
- Ranking
- Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
- Verification
- Every listed company carries at least one verified work email, 844 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
- Refresh
- This page's figures were pulled from the company graph on September 10, 2026. Lists refresh periodically as the graph is re-checked.
- Corrections
- Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.
Defense cybersecurity companies by metro in the United States
- Defense cybersecurity companies in Washington91
- Defense cybersecurity companies in New York84
- Defense cybersecurity companies in Houston58
- Defense cybersecurity companies in Austin57
- Defense cybersecurity companies in Columbia56
- Defense cybersecurity companies in Arlington56
- Defense cybersecurity companies in Miami54
Frequently asked
What is RevenueBase Smart Search?
RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names defense cybersecurity companies, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.
How many defense cybersecurity companies are there based in Arlington, United States?
RevenueBase identified 58 defense cybersecurity companies headquartered in Arlington, United States as of September 2026, matched on each company's own description of what it does rather than its industry code.
What is the largest company on this list?
TWO SIX Technologies, headquartered in Arlington, tops this list with the largest team on record.
Which city has the most defense cybersecurity companies?
Washington leads with 91 headquartered companies, followed by New York (84) and Houston (58).
How do I get contact information for these companies?
A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 844 verified decision-maker contacts tracked across these 58 companies.
How current is this list?
The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 10, 2026.
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About this data
RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.
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