Company lists · Data verified August 2026

Top 25 Cybersecurity and defense software companies based in the United States

Name: Cybersecurity and defense software companies based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Verified Aug 28, 2026 2,175 companies tracked

There are 2,175 cybersecurity and defense software companies headquartered in the United States (RevenueBase, August 2026). RevenueBase tracks 204,771 professional contacts across them, including 30,241 with verified work emails and 86,174 with mobile numbers. New York is the largest hub.

This list covers cybersecurity and defense software companies headquartered in the United States, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Data current as of August 28, 2026.

2,175Companies

204,771Contacts tracked

30,241Verified emails

86,174Mobile numbers

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The 25 largest cybersecurity and defense software companies based in the United States

Ranked by team size

Top 25 of 2,175 cybersecurity and defense software companies based in the United States, ranked by team size, largest first. Data verified Aug 28, 2026. Click a count to unlock that company's people.
#	Company	HQ	Employees	Contacts	Verified emails
1	Northrop Grumman	San Diego, CA	10001+	75,000	1,247
2	L3harris Technologies	Melbourne, FL	10001+	24,757	932
3	Symantec	San Jose, CA	10001+	11,179	876
4	Peraton	San Diego, CA	10001+	10,741	197
5	Trellix	Plano, TX	1,001-5,000	3,490	1,633
6	Ivanti	San Jose	1,001-5,000	2,666	1,783
7	Bitdefender	Fort Lauderdale, FL	1,001-5,000	2,141	1,230
8	Barracuda	Alpharetta, GA	1,001-5,000	2,108	1,463
9	Fortra	Eden Prairie, MN	1,001-5,000	1,640	1,037
10	Forcepoint	Austin, TX	1,001-5,000	1,620	1,084
11	Dynetics, INC	Huntsville, AL	10001+	1,533	41
12	Qinetiq US	Reston, VA	1,001-5,000	1,388	17
13	Thales Cybersecurity Products	Austin, TX	1,001-5,000	1,252	645
14	Imperva	Austin, TX	10001+	1,211	829
15	Agile Defense	Huntsville, AL	1,001-5,000	1,080	402
16	Watchguard Technologies	Seattle, WA	1,001-5,000	1,054	631
17	Radiance Technologies	Baton Rouge, LA	1,001-5,000	1,037	19
18	Tyto Athene, LLC	Amherst, VA	1,001-5,000	858	16
19	Absolute Security	Seattle, WA	501-1,000	789	449
20	STR	Arlington, VA	501-1,000	759	24
21	Bluehalo, An AV Company	Chantilly, VA	1,001-5,000	658	16
22	Telos Corporation	Las Vegas, NV	501-1,000	636	230
23	By Light Professional IT Services	Arlington, VA	1,001-5,000	562	280
24	Ultraviolet Cyber	Phoenix, AZ	501-1,000	517	258
25	Guidance Software	Las Vegas, NV	501-1,000	496	40

Showing 25 of 2,175 cybersecurity and defense software companies based in the United States

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Cybersecurity and defense software companies based in the United States at a glance

As of Aug 28, 2026

11-50Median size (employees)

New YorkLargest hub · 56 HQs

86,174Contacts with mobile numbers

73Emails re-verified in last 30 days

Companies by employee count

1-10

927

11-50

774

51-200

302

201-500

501-1,000

1,001-5,000

10001+

Cybersecurity and defense software companies by metro

Metro	Companies
Cybersecurity and defense software companies in New York	56
Cybersecurity and defense software companies in Washington	53
Cybersecurity and defense software companies in Austin	42
Cybersecurity and defense software companies in Columbia	39
Cybersecurity and defense software companies in Miami	35
Cybersecurity and defense software companies in Arlington	35
Cybersecurity and defense software companies in San Francisco	34

How this list was built

Source: The RevenueBase company graph: 21.3 million companies and 398.9 million professional contacts resolved from primary sources.
Inclusion: Companies whose own business descriptions match “cybersecurity and defense software companies”, with match quality audited by blind human judging, and headquartered in the United States.
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: Contact records re-verify on a rolling cadence; 73 contacts on this list were re-verified in the last 30 days.
Refresh: Lists are refreshed periodically as the underlying company graph is re-verified. Last verified Aug 28, 2026.

Frequently asked

How many cybersecurity and defense software companies are there based in the United States?

There are 2,175 cybersecurity and defense software companies headquartered in the United States as of August 2026 (RevenueBase).

What is the largest company on this list?

Northrop Grumman, headquartered in San Diego, tops this list with the largest team on record.

Which city has the most cybersecurity and defense software companies?

New York leads with 56 headquartered companies, followed by Washington (53) and Austin (42).

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 30,241 verified decision-maker contacts tracked across these 2,175 companies.

How current is this list?

The list is refreshed periodically as the underlying company graph is re-verified. It was last verified on August 28, 2026.

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About this data

RevenueBase is a B2B contact data platform. Its company graph covers 21.3 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, the same data that powers RevenueBase's B2B data products and the free research portal.