Company lists · Data refreshed September 2026

Top 25 Security monitoring services based in the United States

RevenueBase identified 4,578 security monitoring services headquartered in the United States as of September 2026 and tracks 112,769 professional contacts across them, including 40,978 with verified work emails and 39,565 with mobile numbers. New York is the largest hub.

This list covers security monitoring services headquartered in the 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 6, 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 6, 2026 86% judged on-target in blind review
4,578Companies
112,769Contacts tracked
40,978Verified emails
39,565Mobile numbers
Explore all 4,578 companies → Free signup · no credit card · 500 free credits

The 25 largest security monitoring services based in the United States

Ranked by team size
Top 25 of 4,578 security monitoring services based in the United States, ranked by team size, largest first. Data refreshed Sep 6, 2026. Evidence rates how directly each company's own description names security monitoring services: 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.
#CompanyHeadquartersEmployeesContacts
1
Palo Alto NetworksIndirect evidence
Santa Clara, CA, United StatesHQ checked Sep 6, 202610001+18,431

“Palo Alto Networks, the global cybersecurity leader, is shaping the cloud-centric future with technology that is transforming the way people and organizations operate.”

Source: company website · checked Sep 6, 2026
2Roswell, GA, United StatesHQ checked Sep 6, 202610001+3,592

“U.S.”

Source: company website · checked Sep 6, 2026
3
Arctic WolfIndirect evidence
Eden Prairie, MN, United StatesHQ checked Sep 6, 20261,001-5,0003,145

“Every year new technologies, vendors, and solutions emerge-yet despite this constant innovation, high-profile breaches are all over the headlines.”

Source: company website · checked Sep 6, 2026
4
SentineloneIndirect evidence
Mountain View, CA, United StatesHQ checked Sep 6, 20261,001-5,0003,052

“SentinelOne is the world's leading AI-powered cybersecurity platform.”

Source: company website · checked Sep 6, 2026
5
OPTIVIndirect evidence
Leawood, KS, United StatesHQ checked Sep 6, 20261,001-5,0002,222

“Optiv is the cyber advisory and solutions leader, delivering strategic and technical expertise to nearly companies across every major industry.”

Source: company website · checked Sep 6, 2026
6
EveronPartial evidence
Irving, TX, United StatesHQ checked Sep 6, 20261,001-5,0002,045

“Everon is a leading national provider of commercial security, video, fire, sprinkler, and life safety solutions for complex, multi-site businesses and organizations.”

Source: company website · checked Sep 6, 2026
7
Vector SecurityPartial evidence
Warrendale, PA, United StatesHQ checked Sep 6, 20261,001-5,0001,287

“Vector Security® has protected people and property by providing intelligent security solutions tailored to the needs of the customer for more than 50 years.”

Source: company website · checked Sep 6, 2026
8Austin, TX, United StatesHQ checked Sep 6, 20261,001-5,0001,252

“Thales is a global leader in cybersecurity, helping the most trusted organizations in the world protect their most critical applications, data, and identities anywhere at scale.”

Source: company website · checked Sep 6, 2026
9
Guidepoint SecurityPartial evidence
Reston, VA, United StatesHQ checked Sep 6, 20261,001-5,0001,232

“GuidePoint Security provides trusted cybersecurity expertise, solutions, and services that help organizations make informed decisions and minimize risk.”

Source: company website · checked Sep 6, 2026
10
DSI Security ServicesPartial evidence
Dothan, AL, United StatesHQ checked Sep 6, 20261,001-5,0001,190

“DSI Security Services offers armed and unarmed uniformed security guard services.”

Source: company website · checked Sep 6, 2026
11
Titan Security GroupPartial evidence
Chicago, IL, United StatesHQ checked Sep 6, 20261,001-5,0001,138

“At Titan Security Group, we understand that each client is unique, with specific security needs shaped by the type of property and its location.”

Source: company website · checked Sep 6, 2026
12
Brosnan Risk ConsultantsPartial evidence
Pearl River, NY, United StatesHQ checked Sep 6, 20265,001-10,0001,050

“Brosnan Risk Consultants, Ltd.(BRC) is a security risk management firm focusing on physical security, emergency security, disaster preparedness and recovery and management…”

Source: company website · checked Sep 6, 2026
13
ZerofoxIndirect evidence
Baltimore, MD, United StatesHQ checked Sep 6, 2026501-1,000904

“ZeroFox is the solution to discover, validate, and disrupt external cyber threats before they harm revenue or reputation.”

Source: company website · checked Sep 6, 2026
14
NetenrichPartial evidence
San Jose, CA, United StatesHQ checked Sep 6, 2026501-1,000889

“Netenrich is redefining security operations by shifting the focus from "efficiency"(speed) to "efficacy"(comprehensive coverage).”

Source: company website · checked Sep 6, 2026
15Chicago, IL, United StatesHQ checked Sep 6, 2026501-1,000874

“Trustwave, a LevelBlue Company, is a globally recognized cybersecurity leader that reduces cyber risk and fortifies organizations against disruptive and damaging cyber threats.”

Source: company website · checked Sep 6, 2026
16
Security 101Partial evidence
West Palm Beach, FL, United StatesHQ checked Sep 6, 2026501-1,000849

Security 101® is a nationwide leader in designing, installing, and maintaining advanced security systems tailored to the unique needs of organizations of all sizes.”

Source: company website · checked Sep 6, 2026
17
CyderesIndirect evidence
Kansas City, MO, United StatesHQ checked Sep 6, 20261,001-5,000844

“Today’s threatscape is relentless.”

Source: company website · checked Sep 6, 2026
18Uniontown, OH, United StatesHQ checked Sep 6, 202610001+839

Securitas knows Security.”

Source: company website · checked Sep 6, 2026
19San Antonio, TX, United StatesHQ checked Sep 6, 2026201-500702

“Pro-Vigil is the smartest, fastest, most reliable, surveillance and monitoring solution, to enable you to focus on your core business, whether that’s in construction, an auto…”

Source: company website · checked Sep 6, 2026
20
HuntressIndirect evidence
Columbia, MD, United StatesHQ checked Sep 6, 2026501-1,000696

“Protect Your Endpoints, Identities, Logs, and Employees.”

Source: company website · checked Sep 6, 2026
21
BluevoyantIndirect evidence
New York, NY, United StatesHQ checked Sep 6, 2026501-1,000683

“BlueVoyant’s Cyber Defense Platform (CDP) integrates MDR, TPRM, and DRP into a seamless, scalable solution.”

Source: company website · checked Sep 6, 2026
22
Guardian ProtectionPartial evidence
Warrendale, PA, United StatesHQ checked Sep 6, 2026501-1,000677

“Protecting homes and businesses since 1950, Guardian Protection is one of the nation's largest and most highly regarded security companies.”

Source: company website · checked Sep 6, 2026
23
Network IntelligencePartial evidence
Plano, TX, United StatesHQ checked Sep 6, 2026501-1,000641

“At Network Intelligence, we combine our team of 500+ security professionals with Transilience – our cutting-edge AI platform.”

Source: company website · checked Sep 6, 2026
24Los Angeles, CA, United StatesHQ checked Sep 6, 20261,001-5,000626

“Professional Security Consultants, Inc.(PSC) is a world-class provider of security guard services, patrol, investigations, backgrounds, consulting, security screening & specialty…”

Source: company website · checked Sep 6, 2026
25
Alert 360Partial evidence
Tulsa, TX, United StatesHQ checked Sep 6, 2026501-1,000572

“Alert 360 security is a trusted and best-in-class provider of reliable security solutions for homes and businesses.”

Source: company website · checked Sep 6, 2026

Showing 25 of 4,578 security monitoring services based in the United States

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Security monitoring services based in the United States at a glance

As of Sep 6, 2026
11-50Median size (employees)
New YorkLargest hub · 116 HQs
39,565Contacts with mobile numbers
Sep 6, 2026Data refreshed

Companies by employee count

1-10
2,098
11-50
1,649
51-200
568
201-500
126
501-1,000
61
1,001-5,000
42
5,001-10,000
8
10001+
11

Verified emails by last verification

0–30
37,702
31–60
2,655
61–90
23
90–180
15
180+
583

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 security monitoring services, 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 the United States whose own description of what they do matches “security monitoring services”. 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 security monitoring services, and records with no verified work email. Companies headquartered outside United States 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, 40,978 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 6, 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.

Frequently asked

How many security monitoring services are there based in the United States?

RevenueBase identified 4,578 security monitoring services headquartered in the 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?

Palo Alto Networks, headquartered in Santa Clara, tops this list with the largest team on record.

Which city has the most security monitoring services?

New York leads with 116 headquartered companies, followed by Miami (82) and Houston (79).

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 40,978 verified decision-maker contacts tracked across these 4,578 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 6, 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.