Company lists · Data refreshed September 2026

Top 25 Internal messaging platforms based in the United States

RevenueBase identified 187 company matches for internal messaging platforms associated with the United States as of September 2026 and tracks 6,583 professional contacts across them, including 1,062 with verified work emails and 1,792 with mobile numbers. San Francisco is the largest hub.

This list covers company matches for internal messaging platforms associated with the United States, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. 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 RevenueBase SmartSearch · Exact Recorded Sep 4, 2026 How this list was built
187Companies
6,583Contacts tracked
1,062Verified emails
1,792Mobile numbers
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The 25 largest internal messaging platforms based in the United States

Ranked by team size
Top 25 of 187 company matches for internal messaging platforms based in the United States, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Sep 4, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#CompanyRevenueBase SmartSearchHeadquartersEmployeesContacts
1Exact matchSan Francisco, CA, United StatesHQ recorded Sep 4, 20261,001-5,0002,591 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
2Exact matchNY, United StatesHQ recorded Sep 4, 2026n/a760 contacts →

Exact match

“Café helps enterprises drive collaboration, engagement, and cohesion through real-world interactions.”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
3Exact matchSan Francisco, CA, United StatesHQ recorded Sep 4, 2026501-1,000487 contacts →

Exact match

“At Humand, we empower companies to digitize their internal communication, culture, and HR processes in one unified platform, recognizing that the future of mid market and…”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
4Exact matchOmaha, NE, United StatesHQ recorded Sep 4, 202651-200426 contacts →

Exact match

“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…”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
5Exact matchSan Francisco, CA, United StatesHQ recorded Sep 4, 2026201-500270 contacts →

Exact match

“The Firstup Intelligent Communication Platform equips organizations to improve productivity, retention, labor efficiency, safety compliance, and revenue performance by activating…”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
6Exact matchBoston, MA, United StatesHQ recorded Sep 4, 2026501-1,000103 contacts →

Exact match

“Fuze is a global cloud communications and collaboration software platform for the enterprise that was acquired by 8x8.”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
7Exact matchDenver, CO, United StatesHQ recorded Sep 4, 202651-20097 contacts →

Exact match

“Finishing your product shouldn’t be harder than building it.”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
8Exact matchArlington, VA, United StatesHQ recorded Sep 4, 202651-20083 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
9Exact matchNew York, NY, United StatesHQ recorded Sep 4, 202651-20079 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
10Exact matchAustin, TX, United StatesHQ recorded Sep 4, 202611-5074 contacts →

Exact match

“Mio is a secure middleware that unlocks cross-platform messaging, file sharing, and meeting initiation for enterprise organizations that use Google Workspace and Microsoft 365…”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
11Exact matchSan Francisco, CA, United StatesHQ recorded Sep 4, 202651-20063 contacts →

Exact match

“Swit is every team's work hub that consolidates collaboration essentials in one place - task, chat, goals, approvals, and integrations.”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
12Exact matchBloomington, IL, United StatesHQ recorded Sep 4, 202611-5062 contacts →

Exact match

“Business Class Team Texting to help Sales and Service Teams!”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
13Exact matchNew York, NY, United StatesHQ recorded Sep 4, 202651-20049 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
14Exact matchNew York, NY, United StatesHQ recorded Sep 4, 202651-20048 contacts →

Exact match

“Zenzap is the professional work chat app trusted by businesses worldwide.”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
15Exact matchSan Francisco, CA, United StatesHQ recorded Sep 4, 202651-20036 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
16Exact matchCambridge, MA, United StatesHQ recorded Sep 4, 202611-5035 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
17Exact matchBlue Ash, OH, United StatesHQ recorded Sep 4, 202651-20030 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
18Exact matchSan Francisco, CA, United StatesHQ recorded Sep 4, 202611-5026 contacts →

Exact match

“Hey there!”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
19Exact matchWilmington, DE, United StatesHQ recorded Sep 4, 202651-20026 contacts →

Exact match

“MessageSpring simplifies your communication efforts by reaching audiences who are most important to you through a single platform, with the right message, at the right time, in…”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
20Exact matchLaguna Beach, CA, United StatesHQ recorded Sep 4, 2026501-1,00025 contacts →

Exact match

“At 360 SMS, we transform and simplify communication for Salesforce users with our native messaging solution, enhancing connectivity through automated, streamlined, and omnichannel…”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
21Exact matchSan Francisco, CA, United StatesHQ recorded Sep 4, 20261-1022 contacts →

Exact match

“We believe it should be easy to share the right information with the right people, both inside and outside of your team.”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
22Exact matchMill Valley, CA, United StatesHQ recorded Sep 4, 202611-5021 contacts →

Exact match

“Avochato is an AI messaging platform built to help businesses have better conversations with their customers.”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
23Exact matchSan Francisco, CA, United StatesHQ recorded Sep 4, 202611-5019 contacts →

Exact match

“Voxer is a high-performance messaging app that combines the power of live voice with text, photos and videos.”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
24Exact matchPleasanton, CA, United StatesHQ recorded Sep 4, 202611-5017 contacts →

Exact match

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

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase
25Exact matchSan Francisco, CA, United StatesHQ recorded Sep 4, 202611-5016 contacts →

Exact match

“Threads is an all-in-one communication platform designed for makers.”

Recorded in the RevenueBase company graph · Sep 4, 2026 · View company records in RevenueBase

Showing 25 of 187 internal messaging platforms based in the United States

See the full list, filter by size, metro and specialty, and access 1,062 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Internal messaging platforms based in the United States at a glance

As of Sep 4, 2026
16.1%Verified-email coverage
27.2%Mobile-number coverage
35.2Average contacts per company
11-50Median size (employees)
16.6%Largest-city concentration · San Francisco
Sep 4, 2026Page data refreshed

Companies by employee count

1-10
74
11-50
74
51-200
27
201-500
6
501-1,000
3
1,001-5,000
1
10001+
1

Freshness & accuracy

How recently the business emails on this list were verified

Email last verified

How this list was built

The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.

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
Company records associated with the United States whose business descriptions match “internal messaging platforms” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
RevenueBase SmartSearch
Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
Public preview
The public preview omits records without a verified work email. Where headquarters information is recorded, preview rows are also filtered to this page’s location. Dataset totals and geographic summaries describe the full matched records before these preview filters.
Match quality
RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
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 displayed company carries at least one verified work email. RevenueBase tracks 1,062 professional contacts with verified work emails across the full matched dataset. 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.
Record context
Company records and descriptions can change. Check the company's website for its current services and locations.

Internal messaging platforms by metro

Frequently asked

What is RevenueBase SmartSearch?

RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “internal messaging platforms”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many internal messaging platforms are there based in the United States?

RevenueBase identified 187 company matches for internal messaging platforms associated with the United States as of September 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.

What is the largest company on this list?

SLACK tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city has the most internal messaging platforms?

San Francisco leads with 31 company records, followed by New York (12) and Chicago (8).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 1,062 professional contacts with verified work emails tracked across these 187 companies; direct dials are available where recorded.

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.