Company lists · Data refreshed September 2026

Top 21 IT security consulting firms based in Fairfax, United States

Name: IT security consulting firms based in Fairfax, United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 4, 2026 37 companies tracked

RevenueBase identified 37 IT security consulting firms headquartered in Fairfax, United States as of September 2026 and tracks 425 professional contacts across them, including 158 with verified work emails. New York is the largest hub.

This list covers IT security consulting firms headquartered in Fairfax, 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, how directly it supports the match, and when it was last checked. Data refreshed September 4, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, 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.

How to read this list HQ checked on every row Match evidence on every row Refreshed Sep 4, 2026 86% judged on-target in blind review

37Companies

425Contacts tracked

158Verified emails

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The 21 largest IT security consulting firms based in Fairfax, United States

Ranked by team size

Top 21 of 37 IT security consulting firms based in Fairfax, United States, ranked by team size, largest first. Data refreshed Sep 4, 2026. Evidence rates how directly each company's own description names IT security consulting firms: strong (names it), partial (names part of it), indirect (matched on its full profile rather than the summary shown). Click a count to unlock that company's people.
#	Company	Headquarters	Employees	Contacts
1	OnpointPartial evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	11-50	104
	“OnPoint is a technology and consulting services partner helping government leaders secure their systems, effectively operate, and deliver critical services in today’s increasingly…” Source: company website · checked Sep 4, 2026
2	JCS Solutions LLCIndirect evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	51-200	93
	“JCS Solutions is a premier cybersecurity and technology solutions provider.” Source: company website · checked Sep 4, 2026
3	True Zero TechnologiesPartial evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	51-200	50
	“True Zero Technologies ("True Zero") is a seasoned, Veteran-Owned Small Business (VOSB) specializing in comprehensive cybersecurity and consulting services.” Source: company website · checked Sep 4, 2026
4	Sensei EnterprisesIndirect evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	11-50	20
	“Sensei Enterprises, Inc.” Source: company website · checked Sep 4, 2026
5	Polito, INCIndirect evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	11-50	16
	Source: company website · checked Sep 4, 2026
6	Senet InternationalPartial evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	11-50	16
	“SeNet International Corporation is a company of information technology consulting professionals committed to helping public and private sector organizations securely operate their…” Source: company website · checked Sep 4, 2026
7	AssuritIndirect evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	11-50	13
	“CAGE 6VE87 \| UEI DL3JL6J1XG98 \| SBA 8(a)\| 8(a) STARS \| HACS SINs \| CMMI-SVC \| ISO 9001 \| ISO 27001 \| ISO \| Assurit, an 8(a) certified and recognized leader in cybersecurity, is…” Source: company website · checked Sep 4, 2026
8	Jacob & SundstromIndirect evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	1,001-5,000	13
	“Jacob & Sundstrom, Inc.” Source: company website · checked Sep 4, 2026
9	Elite Systems INCPartial evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	11-50	9
	“Systems Integration, Cloud Migration, Software Development, Network Security, Applications Security, Industrial Cyber Security Quality Assurance, RF Benchmark, Wireless…” Source: company website · checked Sep 4, 2026
10	Deci TechnologyStrong evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	11-50	9
	“IT consulting company providing cyber security, analytics and data science services.” Source: company website · checked Sep 4, 2026
11	Itfrastructure, Inc. D B A ItinfraPartial evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	11-50	8
	“Implementing Zero Trust Architecture to Enhance Security, Productivity, and Data Integrity, while Optimizing for Future-Readiness and Mission Success 8(a) Certified Small Business…” Source: company website · checked Sep 4, 2026
12	Datalock Consulting GroupPartial evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	11-50	8
	“A Cybersecurity Firm Focused on Securing Mission-Critical Systems, Protecting Supply Chains, and Safeguarding Digital Assets Within Federal Agencies, While Ensuring Regulatory…” Source: company website · checked Sep 4, 2026
13	PurplesecIndirect evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	11-50	8
	“Committed to Intelligent Risk Defense.” Source: company website · checked Sep 4, 2026
14	CapsentinelPartial evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	1-10	6
	“CapSentinel is a Small Business that offers world class Information Technology (IT) Risk, Cybersecurity, and financial management solutions to help commercial and federal…” Source: company website · checked Sep 4, 2026
15	Cleared SystemsIndirect evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	11-50	4
	“Headquartered in Fairfax, VA, Cleared Systems specializes in helping federal contractors and highly regulated organizations meet cybersecurity and compliance requirements under…” Source: company website · checked Sep 4, 2026
16	Msnet Solutions, LLCPartial evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	1-10	3
	“MSNET SOLUTIONS is owned and operated by professional IT consultants who know what it takes to design, implement, and support secure networks utilizing the latest technologies…” Source: company website · checked Sep 4, 2026
17	Prosoft Systems IntlPartial evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	11-50	3
	“A professional services firm focused on helping organizations successfully mitigate threats with Microsoft Security, Compliance, and Identity solutions.” Source: company website · checked Sep 4, 2026
18	Waveport SecurityPartial evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	1-10	2
	“LEADING CYBER SOLUTIONS WavePort Security applies proven tools, professional services, and years of cyber-focused experience to create security strategies that provide unrivaled…” Source: company website · checked Sep 4, 2026
19	GrocyberPartial evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	1-10	2
	“GroCyber brings over 4 decades of cyber security experience supporting large enterprise security programs and growing start-up and turn-around companies.” Source: company website · checked Sep 4, 2026
20	Xpect Solutions, INCStrong evidence	Fairfax, VA, United StatesHQ checked Sep 4, 2026	51-200	1
	“If securing your IT systems, network infrastructure, and facilities is foremost on your mind, Xpect Solutions can help.” Source: company website · checked Sep 4, 2026
21	Kobel Systems LLCPartial evidence	Fairfax, VT, United StatesHQ checked Sep 4, 2026	1-10	1
	“In today’s fast-paced and competitive market, businesses must boost revenue, cut costs, and streamline operations, all while prioritizing security.” Source: company website · checked Sep 4, 2026

Showing 21 of 37 IT security consulting firms based in Fairfax, United States

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IT security consulting firms based in Fairfax, United States at a glance

As of Sep 4, 2026

11-50Median size (employees)

New YorkLargest hub · 239 HQs

Contacts with mobile numbers

Sep 4, 2026Data refreshed

Companies by employee count

1-10

11-50

51-200

1,001-5,000

Email recency for this list is measured across the whole United States list rather than this city, so it is reported there. Company counts and contact totals on this page are exact for Fairfax, over 37 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 IT security consulting firms, so some rows will be adjacent to the category rather than pure plays. The description and evidence 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 SmartSearch, the natural-language company search available to every RevenueBase user.
What qualifies: Companies headquartered in Fairfax, United States whose own description of what they do matches “IT security consulting firms”. Matching reads each company's description, not its industry code or its name.
What we exclude: Companies whose own description does not clearly place them among IT security consulting firms, and records with no verified work email. Companies headquartered outside Fairfax 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 an evidence 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, 158 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 4, 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.

IT security consulting firms by metro in the United States

Frequently asked

How many IT security consulting firms are there based in Fairfax, United States?

RevenueBase identified 37 IT security consulting firms headquartered in Fairfax, 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?

Onpoint, headquartered in Fairfax, tops this list with the largest team on record.

Which city has the most IT security consulting firms?

New York leads with 239 headquartered companies, followed by Houston (148) and Atlanta (139).

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 158 verified decision-maker contacts tracked across these 37 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 4, 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 SmartSearch, 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.