Company lists · Data refreshed September 2026
Top 25 Cybersecurity defense contractors based in Herndon, United States
RevenueBase identified 39 cybersecurity defense contractors headquartered in Herndon, United States as of September 2026 and tracks 3,498 professional contacts across them, including 372 with verified work emails. New York is the largest hub.
This list covers cybersecurity defense contractors headquartered in Herndon, 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 14, 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 cybersecurity defense contractors based in Herndon, United States
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 1,949 contacts → | ||||
Partial evidence “Paragon Systems employs over 10,500 professionals in specialized operations providing security, fire, investigations, inspections, cybersecurity, risk management, and mission…” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 2 | 214 contacts → | ||||
Partial evidence “Sotera Defense Solutions (Sotera) has joined KeyW Corporation.” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 3 | 122 contacts → | ||||
Indirect evidence “For 30 years, NetCentrics has excelled as an innovative technology solutions provider for the U.S.” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 4 | 117 contacts → | ||||
Partial evidence “Foxhole Technology is a thought-leading technology firm offering a robust suite of cybersecurity, software development, systems engineering, and test & evaluation solutions for…” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 5 | 101 contacts → | ||||
Indirect evidence “Founded in 2001, Indigo IT is an award winning information technology consulting and services company.” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 6 | 97 contacts → | ||||
Indirect evidence “BlackHorse Solutions, Inc.” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 7 | 94 contacts → | ||||
Indirect evidence “Truestone provides full lifecycle, business driven technology and information security-oriented services and solutions across the public and private sectors.” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 8 | 59 contacts → | ||||
Indirect evidence “Chameleon Consulting Group, LLC was founded by a small group of professionals with extensive experience in cyber operations, software engineering, data analysis, and physical…” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 9 | 48 contacts → | ||||
Indirect evidence “Your Vision Achieved.” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 10 | 45 contacts → | ||||
Indirect evidence “Cyber Security (Vulnerability Assessments, 24/7 Operations, Hunt Teams, Risk Management, Cyber Response) Program Management (Acquisition, Financial, Technology Insertion) System…” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 11 | 38 contacts → | ||||
Indirect evidence “Sphinx Solutions is an entrepreneurial cyber security company that helps private- and public-sector organizations take advantage of solutions that match today’s security…” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 12 | 34 contacts → | ||||
Partial evidence “Network Depot has been serving the DC Metro area since 1991, providing technical support and cybersecurity consulting.” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 13 | 33 contacts → | ||||
Partial evidence “In October 2021, OneZero Solutions, LCC (OneZero), a leading federal cybersecurity and IT solutions provider, announced its acquisition of Right-Sized Solutions Inc.(RSSi), a…” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 14 | 27 contacts → | ||||
Indirect evidence “Roka Security, LLC is a computer security firm located in the Washington D.C.” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 15 | 26 contacts → | ||||
Partial evidence “At IPNS, we work exclusively in the Federal marketplace, providing agencies in the Civilian, Defense and Intelligence communities with advanced IT systems solutions and…” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 16 | 16 contacts → | ||||
Indirect evidence “KLC Network Services, Incorporated is an SBA business based in Herndon, Virginia that provides technical solutions to our valued customers.” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 17 | 13 contacts → | ||||
Partial evidence “ioSENTRIX is a Cybersecurity Consulting firm.” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 18 | 11 contacts → | ||||
Partial evidence “After years of experience working with the Federal Government, it is apparent that cybersecurity is not operating at its highest potential.” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 19 | 9 contacts → | ||||
Indirect evidence “At Reckon, we are the vanguard of a new era in government IT consulting, a small but mighty startup driven by a mission to empower government agencies with cutting-edge technology…” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 20 | 6 contacts → | ||||
Indirect evidence Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 21 | 4 contacts → | ||||
Partial evidence “Aristi is a cybersecurity firm based in the Washington DC metro area.” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 22 | 3 contacts → | ||||
Partial evidence “SI is a professional services firm and government contractor in the investigations, intelligence, and cyber sectors, based in the Washington DC metropolitan area, operating…” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 23 | 1 contacts → | ||||
Indirect evidence “Westway Enterprises LLC is a transformational security company providing first of its kind security services to the U.S.” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 24 | 1 contacts → | ||||
Partial evidence “Information & Infrastructure Technologies Corporation (IIT) is an American information security, technology services and defense consultancy founded in 1997.” Source: RevenueBase Database · checked Sep 14, 2026Thanks. The Data Team will review it. | |||||
| 25 | 1 contacts → | ||||
Indirect evidence “RamWreck consulting provides information security and cloud architecture services to various organizations.” Source: RevenueBase Database · checked Sep 14, 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: cybersecurity defense contractors. 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 cybersecurity defense contractors.
- Partial evidence
- Its own public description names part of cybersecurity defense contractors, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name cybersecurity defense contractors. 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 39 cybersecurity defense contractors based in Herndon, United States
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Cybersecurity defense contractors based in Herndon, United States at a glance
As of Sep 14, 2026Companies by employee count
Email recency for this list is measured across the whole United States list rather than for Herndon, so it is reported there. Company counts and contact totals on this page are exact for Herndon, over 39 companies.
How 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 cybersecurity defense contractors, 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 Herndon, United States whose own description of what they do matches “cybersecurity defense contractors”. 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 cybersecurity defense contractors), 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 cybersecurity defense contractors, and records with no verified work email. Companies headquartered outside Herndon 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, 372 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 14, 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.
Cybersecurity defense contractors by metro in the United States
- Cybersecurity defense contractors in New York136
- Cybersecurity defense contractors in Washington113
- Cybersecurity defense contractors in Atlanta89
- Cybersecurity defense contractors in Austin88
- Cybersecurity defense contractors in Houston86
- Cybersecurity defense contractors in Miami79
- Cybersecurity defense contractors in Dallas76
- Cybersecurity defense contractors in Tampa71
- Cybersecurity defense contractors in Chicago69
- Cybersecurity defense contractors in Arlington65
- Cybersecurity defense contractors in Columbia63
- Cybersecurity defense contractors in San Francisco62
- Cybersecurity defense contractors in Reston53
- Cybersecurity defense contractors in San Diego53
- Cybersecurity defense contractors in Mclean48
- Cybersecurity defense contractors in Los Angeles47
- Cybersecurity defense contractors in San Antonio46
- Cybersecurity defense contractors in Alexandria43
- Cybersecurity defense contractors in Boston41
- Cybersecurity defense contractors in Denver40
- Cybersecurity defense contractors in Huntsville40
- Cybersecurity defense contractors in Charlotte39
- Cybersecurity defense contractors in Herndon39
- Cybersecurity defense contractors in Las Vegas37
- Cybersecurity defense contractors in Orlando37
- Cybersecurity defense contractors in Baltimore36
- Cybersecurity defense contractors in Phoenix35
- Cybersecurity defense contractors in Fairfax33
- Cybersecurity defense contractors in Ashburn32
- Cybersecurity defense contractors in Sheridan31
- Cybersecurity defense contractors in Seattle29
- Cybersecurity defense contractors in Raleigh28
- Cybersecurity defense contractors in Wilmington28
- Cybersecurity defense contractors in Chantilly27
- Cybersecurity defense contractors in Vienna27
- Cybersecurity defense contractors in San Jose26
- Cybersecurity defense contractors in Plano25
- Cybersecurity defense contractors in Scottsdale25
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 cybersecurity defense contractors, 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 cybersecurity defense contractors are there based in Herndon, United States?
RevenueBase identified 39 cybersecurity defense contractors headquartered in Herndon, 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?
Paragon Systems INC, headquartered in Herndon, tops this list with the largest team on record.
Which city has the most cybersecurity defense contractors?
New York leads with 136 headquartered companies, followed by Washington (113) and Atlanta (89).
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 372 verified decision-maker contacts tracked across these 39 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 14, 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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