Company lists · Data refreshed September 2026

Top 25 Internal communications software companies based in the United States

RevenueBase identified 128 internal communications software companies headquartered in the United States as of September 2026 and tracks 4,760 professional contacts across them, including 650 with verified work emails. San Francisco is the largest hub.

This list covers internal communications 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. 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.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 14, 2026 86% judged on-target in blind review
128Companies
4,760Contacts tracked
650Verified emails
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The 25 largest internal communications software companies based in the United States

Ranked by team size
Top 25 of 128 internal communications software companies based in the United States, ranked by team size, largest first. Data refreshed Sep 14, 2026. RevenueBase Smart Search rates how each company's information relates to internal communications software companies: 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.
#CompanyRevenueBase Smart SearchHeadquartersEmployeesContacts
1Indirect evidenceSan Francisco, CA, United StatesHQ checked Sep 14, 20261,001-5,0002,619 contacts →

Indirect evidence

“Slack is on a mission to make people's working lives simpler, more pleasant and more productive.”

Source: RevenueBase Database · checked Sep 14, 2026
2Strong evidenceOmaha, NE, United StatesHQ checked Sep 14, 202651-200447 contacts →

Strong evidence

“Workshop is a modern, purpose-built internal communications platform that helps teams create, send, manage, and measure employee communications in one place, starting with email…”

Source: RevenueBase Database · checked Sep 14, 2026
3Partial evidenceAustin, TX, United StatesHQ checked Sep 14, 2026501-1,000164 contacts →

Partial evidence

“Jive is the leading provider of modern communication and collaboration solutions for business.”

Source: RevenueBase Database · checked Sep 14, 2026
4Indirect evidenceSan Francisco, CA, United StatesHQ checked Sep 14, 2026n/a153 contacts →

Indirect evidence

“With TextExpander, created by Smile, you can communicate smarter.”

Source: RevenueBase Database · checked Sep 14, 2026
5Indirect evidencePalo Alto, CA, United StatesHQ checked Sep 14, 202651-200152 contacts →

Indirect evidence

“Mattermost is the leading collaboration platform for mission-critical work.”

Source: RevenueBase Database · checked Sep 14, 2026
6Indirect evidenceBoston, MA, United StatesHQ checked Sep 14, 202651-200152 contacts →

Indirect evidence

“Blink is the mobile-first employee experience platform that connects your people, systems, and culture in one super-app.”

Source: RevenueBase Database · checked Sep 14, 2026
7Strong evidenceScotts Valley, CA, United StatesHQ checked Sep 14, 202651-20089 contacts →

Strong evidence

“ROI Communication is a 100% employee-owned internal communications company focused on helping the world’s leading businesses achieve their very best through inspired employee…”

Source: RevenueBase Database · checked Sep 14, 2026
8Strong evidenceArlington, VA, United StatesHQ checked Sep 14, 202651-20078 contacts →

Strong evidence

“Axios HQ is the first internal communications management platform to equip organizations with the tools, data, and best practices to be world-class communicators.”

Source: RevenueBase Database · checked Sep 14, 2026
9Partial evidenceNew York City, NY, United StatesHQ checked Sep 14, 202651-20077 contacts →

Partial evidence

“Amplispot is the mobile-first company communications platform, used by organizations to increase productivity and empower advocacy by informing and engaging employees with timely…”

Source: RevenueBase Database · checked Sep 14, 2026
10Indirect evidenceNew York, NY, United StatesHQ checked Sep 14, 202651-20063 contacts →

Indirect evidence

“In 2024, LiveTiles joined forces with Omnia, an award-winning intranet solution that significantly improves employee engagement.”

Source: RevenueBase Database · checked Sep 14, 2026
11Partial evidenceNew York, NY, United StatesHQ checked Sep 14, 202651-20048 contacts →

Partial evidence

“Axero provides easy-to-use intranet software that boosts productivity, unifies your people, and helps your company thrive.”

Source: RevenueBase Database · checked Sep 14, 2026
12Strong evidenceGreenland, NH, United StatesHQ checked Sep 14, 202611-5043 contacts →

Strong evidence

“PoliteMail is an internal communications measurement platform for Microsoft Outlook and Office365.”

Source: RevenueBase Database · checked Sep 14, 2026
13Indirect evidenceLos Angeles, CA, United StatesHQ checked Sep 14, 202651-20039 contacts →

Indirect evidence

“Haystack reinvented the intranet for the future of work, with a focus on seamless integrations, powerful search capabilities, and consumer-grade design.”

Source: RevenueBase Database · checked Sep 14, 2026
14Partial evidenceAustin, TX, United StatesHQ checked Sep 14, 202651-20036 contacts →

Partial evidence

“L Squared Digital provides turn-key enterprise corporate communication solutions with a mandate to improve culture and effective communication worldwide.”

Source: RevenueBase Database · checked Sep 14, 2026
15Partial evidenceCambridge, MA, United StatesHQ checked Sep 14, 202611-5036 contacts →

Partial evidence

“HubEngage™ is a unified employee communications, engagement, recognition and instant messaging platform.”

Source: RevenueBase Database · checked Sep 14, 2026
16Indirect evidenceSan Francisco, CA, United StatesHQ checked Sep 14, 202651-20036 contacts →

Indirect evidence

“Agility is the greatest advantage in the modern marketplace.”

Source: RevenueBase Database · checked Sep 14, 2026
17Partial evidenceBlue Ash, OH, United StatesHQ checked Sep 14, 202651-20027 contacts →

Partial evidence

“Cerkl Broadcast is the premier, forward-thinking employee communications suite.”

Source: RevenueBase Database · checked Sep 14, 2026
18Indirect evidencePleasanton, CA, United StatesHQ checked Sep 14, 202611-5017 contacts →

Indirect evidence

“Communicate with your employees in the simplest way possible.”

Source: RevenueBase Database · checked Sep 14, 2026
19Partial evidenceSan Francisco, CA, United StatesHQ checked Sep 14, 20261-1014 contacts →

Partial evidence

“Zelo redefines how companies communicate internally.”

Source: RevenueBase Database · checked Sep 14, 2026
20Indirect evidencePortland, OR, United StatesHQ checked Sep 14, 202611-509 contacts →

Indirect evidence

“Kavi was acquired by Higher Logic in February 2017.”

Source: RevenueBase Database · checked Sep 14, 2026
21Partial evidenceBellevue, WA, United StatesHQ checked Sep 14, 202651-2009 contacts →

Partial evidence

“Intentional is creating innovative software that will transform the way organizations collaborate to create and share ideas.”

Source: RevenueBase Database · checked Sep 14, 2026
22Indirect evidenceBellevue, WA, United StatesHQ checked Sep 14, 202611-507 contacts →

Indirect evidence

“Proze empowers organizations to turn email into a strategic advantage.”

Source: RevenueBase Database · checked Sep 14, 2026
23Partial evidenceBrooklyn, United StatesHQ checked Sep 14, 202651-2007 contacts →

Partial evidence

“Repticity is an all-in-one communication and work management platform.”

Source: RevenueBase Database · checked Sep 14, 2026
24Partial evidenceWest Chester, PA, United StatesHQ checked Sep 14, 202611-507 contacts →

Partial evidence

“With more than two decades of employee, change and external communications experience in an array of industries, MAC4 understands your communications priorities and partners with…”

Source: RevenueBase Database · checked Sep 14, 2026
25Partial evidenceMiami, FL, United StatesHQ checked Sep 14, 202611-506 contacts →

Partial evidence

“Konverse is an all-in-one communication platform designed for nondesk workers.”

Source: RevenueBase Database · checked Sep 14, 2026

Showing 25 of 128 internal communications software companies based in the United States

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Internal communications software companies based in the United States at a glance

As of Sep 14, 2026
13.7%Verified-email coverage
37.2Average contacts per company
11-50Median size (employees)
13.3%Largest-city concentration · San Francisco
Sep 14, 2026Page data refreshed

Companies by employee count

1-10
52
11-50
49
51-200
20
201-500
4
501-1,000
1
1,001-5,000
1
10001+
1

Email recency for this list is measured worldwide rather than for United States, so it is reported there. Company counts and contact totals on this page are exact for United States, over 128 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 internal communications software companies, 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 the United States whose own description of what they do matches “internal communications software companies”. 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 internal communications software companies), 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 internal communications software companies, 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 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, 650 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.

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 internal communications software companies, 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 internal communications software companies are there based in the United States?

RevenueBase identified 128 internal communications software companies 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?

SLACK, headquartered in San Francisco, tops this list with the largest team on record.

Which city has the most internal communications software companies?

San Francisco leads with 17 headquartered companies, followed by New York (11) and Mountain View (5).

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 650 verified decision-maker contacts tracked across these 128 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.