Company lists · Data refreshed September 2026

Top 25 Outsourced ciso services based in Chicago, United States

Name: Outsourced ciso services based in Chicago, United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 21, 2026 52 companies tracked

RevenueBase identified 52 outsourced ciso services headquartered in Chicago, United States as of September 2026 and tracks 869 professional contacts across them, including 540 with verified work emails. New York is the largest hub.

This list covers outsourced ciso services headquartered in Chicago, 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 21, 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.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 21, 2026 86% judged on-target in blind review

52Companies

869Contacts tracked

540Verified emails

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The 25 largest outsourced ciso services based in Chicago, United States

Ranked by team size

Top 25 of 52 outsourced ciso services based in Chicago, United States, ranked by team size, largest first. Data refreshed Sep 21, 2026. RevenueBase Smart Search rates how each company's information relates to outsourced ciso services: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#	Company	RevenueBase Smart Search	Headquarters	Employees	Contacts
1	Vikingcloud	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	1,001-5,000	628 contacts →
	Indirect evidence “VikingCloud delivers battle-tested cybersecurity and compliance solutions that simply work.” Source: RevenueBase Database · checked Sep 21, 2026
2	Entara	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	51-200	69 contacts →
	Indirect evidence “Experiencing a security incident?” Source: RevenueBase Database · checked Sep 21, 2026
3	Ravenswood Technology Group	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	11-50	21 contacts →
	Indirect evidence “At Ravenswood Technology Group, we don’t just offer our customers cybersecurity solutions – we deliver value and expertise you can rely on as needs and risks change.” Source: RevenueBase Database · checked Sep 21, 2026
4	Harrington Technology & Associates, INC	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	11-50	9 contacts →
	Indirect evidence “HTA Technology Security Consulting (HTA) is a certified Woman-Owned, Small, Disadvantaged, Minority business with offices in Chicago, IL, and the Washington DC corridor.” Source: RevenueBase Database · checked Sep 21, 2026
5	Data Defenders, LLC	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	11-50	9 contacts →
	Indirect evidence “Data Defenders is at the forefront of Managed Cybersecurity Operations Providers (MCOP), specializing in safeguarding municipalities through our exclusive Regional Security…” Source: RevenueBase Database · checked Sep 21, 2026
6	Cyber Bark LLC	Indirect evidence	Chicago, United StatesHQ checked Sep 21, 2026	51-200	7 contacts →
	Indirect evidence “At Cyber Bark, we bring 100 years of collective experience to the table, serving businesses across the US from our base in Illinois.” Source: RevenueBase Database · checked Sep 21, 2026
7	Vitaltech	Partial evidence	Chicago, United StatesHQ checked Sep 21, 2026	1-10	7 contacts →
	Partial evidence “vitaltech is Chicago’s leading provider of outsourced IT services, dedicated to delivering a genuine, human IT experience through a high-energy approach and adaptable products and…” Source: RevenueBase Database · checked Sep 21, 2026
8	Amol Solutions	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	1-10	7 contacts →
	Indirect evidence “Amol Solutions strives to be a leader in cybersecurity services for organizations of all sizes.” Source: RevenueBase Database · checked Sep 21, 2026
9	Crossrealms Middle East	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	51-200	6 contacts →
	Indirect evidence “CrossRealms is a premier Cybersecurity and Managed Services provider with multiple locations in the United States, Canada, Europe, MENA region, and Asia.” Source: RevenueBase Database · checked Sep 21, 2026
10	Clairos	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	51-200	6 contacts →
	Indirect evidence “Clairos is a cybersecurity company that helps organizations build stronger, more manageable security programs through a practical, tailored approach.” Source: RevenueBase Database · checked Sep 21, 2026
11	Network Aegis	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	1-10	5 contacts →
	Indirect evidence “Welcome to Network Aegis!” Source: RevenueBase Database · checked Sep 21, 2026
12	ESG	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	1-10	5 contacts →
	Indirect evidence “We operationalize, economize, and secure enterprise organizations by understanding their business outcomes and connecting them with proven, venture-backed startups recommended by…” Source: RevenueBase Database · checked Sep 21, 2026
13	Urbane Security	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	11-50	4 contacts →
	Indirect evidence “Urbane Security is an information security firm that provides specially tailored security and compliance solutions that empower the Fortune 500 to securely focus on their ultimate…” Source: RevenueBase Database · checked Sep 21, 2026
14	Apex IT And Cybersecurity Solutions	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	51-200	4 contacts →
	Indirect evidence “Apex IT and Cybersecurity Solutions Inc is a leading Technology and Cybersecurity services firm based in Chicago, IL.” Source: RevenueBase Database · checked Sep 21, 2026
15	Cybermetis	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	11-50	4 contacts →
	Indirect evidence “CyberMetis has collected some of the industry’s best minds and tools.” Source: RevenueBase Database · checked Sep 21, 2026
16	Wolf Point Security	Indirect evidence	Chicago, United StatesHQ checked Sep 21, 2026	1-10	4 contacts →
	Indirect evidence “Wolf Point Security is a cyber security consulting firm, plain and simple.” Source: RevenueBase Database · checked Sep 21, 2026
17	RED Door Technologies	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	1-10	3 contacts →
	Indirect evidence “Red Door Technologies has protected Chicago small businesses since 2009.” Source: RevenueBase Database · checked Sep 21, 2026
18	Lightway Solutions	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	1-10	3 contacts →
	Indirect evidence “Small & Medium-Sized Businesses power the world.” Source: RevenueBase Database · checked Sep 21, 2026
19	Quantum Vigilance	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	1-10	3 contacts →
	Indirect evidence “Quantum's Virtual Chief Information Security Officer (QvCISO) Services can help guide your company towards effective cybersecurity and compliance.” Source: RevenueBase Database · checked Sep 21, 2026
20	Protectedit	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	201-500	2 contacts →
	Indirect evidence “Founded 2019 in Chicago by a team with industry expertise, ProtectedIT is a Managed Security Services Provider delivering remote infrastructure management, cloud adoption…” Source: RevenueBase Database · checked Sep 21, 2026
21	CIO Services	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	1-10	1 contacts →
	Indirect evidence “CIO Services provides IT strategy consulting and experienced IT leadership using a "CIO On-Demand" model.” Source: RevenueBase Database · checked Sep 21, 2026
22	Zakti Security Labs	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	1-10	1 contacts →
	Indirect evidence Source: RevenueBase Database · checked Sep 21, 2026
23	Erus IT & Security	Indirect evidence	Chicago, United StatesHQ checked Sep 21, 2026	1-10	1 contacts →
	Indirect evidence “The mission of Erus Consulting is to consistently deliver excellence in information security consulting and advisory services, endeavoring to be your preferred partner for all…” Source: RevenueBase Database · checked Sep 21, 2026
24	Cyfenders	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	1-10	1 contacts →
	Indirect evidence “Cyfenders is a cybersecurity advisory firm based in Chicago.” Source: RevenueBase Database · checked Sep 21, 2026
25	Firuscyber	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 21, 2026	1-10	1 contacts →
	Indirect evidence “We are a small company focusing on assisting other small organizations in securing their network, data, and services.” Source: RevenueBase Database · checked Sep 21, 2026

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: outsourced ciso services. 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 outsourced ciso services.
Partial evidence: Its own public description names part of outsourced ciso services, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name outsourced ciso services. 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 52 outsourced ciso services based in Chicago, United States

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Outsourced ciso services based in Chicago, United States at a glance

As of Sep 21, 2026

62.1%Verified-email coverage

16.7Average contacts per company

1-10Median size (employees)

186.5%Largest-city concentration · New York

Sep 21, 2026Page data refreshed

Companies by employee count

1-10

11-50

51-200

201-500

1,001-5,000

Email recency for this list is measured across the whole United States list rather than for Chicago, so it is reported there. Company counts and contact totals on this page are exact for Chicago, over 52 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 outsourced ciso services, 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 Chicago, United States whose own description of what they do matches “outsourced ciso services”. 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 outsourced ciso services), 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 outsourced ciso services, and records with no verified work email. Companies headquartered outside Chicago 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, 540 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 21, 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.

Outsourced ciso services by metro in the United States

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 outsourced ciso services, 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 outsourced ciso services are there based in Chicago, United States?

RevenueBase identified 52 outsourced ciso services headquartered in Chicago, 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?

Vikingcloud, headquartered in Chicago, tops this list with the largest team on record.

Which city has the most outsourced ciso services?

New York leads with 97 headquartered companies, followed by Atlanta (70) and Austin (63).

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 540 verified decision-maker contacts tracked across these 52 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 21, 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.