Company lists · Data refreshed September 2026

Top 25 Internal communications agencies worldwide

RevenueBase identified 26,030 internal communications agencies worldwide as of September 2026 and tracks 309,463 professional contacts across them, including 72,520 with verified work emails. The United States is the largest market and Sao Paulo the largest hub.

This list covers internal communications agencies worldwide, 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 20, 2026. Country and city lists for internal communications agencies follow the table.

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 20, 2026 86% judged on-target in blind review
26,030Companies
309,463Contacts tracked
72,520Verified emails
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The 25 largest internal communications agencies worldwide

Ranked by team size
Top 25 of 26,030 internal communications agencies worldwide, ranked by team size, largest first. Data refreshed Sep 20, 2026. RevenueBase Smart Search rates how each company's information relates to internal communications agencies: 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
1Partial evidenceChicago, IL, United StatesHQ checked Sep 20, 20265,001-10,0005,385 contacts →

Partial evidence

“Leo Burnett is a communications agency powered by its HumanKind operating system, with the belief that creativity, data and technology work together to transform human behavior…”

Source: RevenueBase Database · checked Sep 20, 2026
2Indirect evidenceNew York, NY, United StatesHQ checked Sep 20, 202610001+4,963 contacts →

Indirect evidence

“IPG Mediabrands is the media and marketing solutions division of Interpublic Group (NYSE: IPG).”

Source: RevenueBase Database · checked Sep 20, 2026
3Indirect evidenceNew York, NY, United StatesHQ checked Sep 20, 202610001+3,874 contacts →

Indirect evidence

“McCann Worldgroup, part of the Interpublic Group (NYSE: IPG), is the irrefutable leader in the business of creativity.”

Source: RevenueBase Database · checked Sep 20, 2026
4Indirect evidenceNew York, NY, United StatesHQ checked Sep 20, 20265,001-10,0003,574 contacts →

Indirect evidence

“J.”

Source: RevenueBase Database · checked Sep 20, 2026
5Partial evidenceNew York, NY, United StatesHQ checked Sep 20, 202610001+1,602 contacts →

Partial evidence

“Y&R is a leading global marketing communications company, with more than 189 offices in 90+ countries.”

Source: RevenueBase Database · checked Sep 20, 2026
6Indirect evidenceMunich, GermanyHQ checked Sep 20, 20265,001-10,0001,298 contacts →

Indirect evidence

“Serviceplan Group is the largest independent, partner-led agency group in Europe.”

Source: RevenueBase Database · checked Sep 20, 2026
7Partial evidenceRio De Janeiro, BrazilHQ checked Sep 20, 2026501-1,0001,277 contacts →

Partial evidence

“FSB Comunicações is an Integrated Communications agency focused on results.”

Source: RevenueBase Database · checked Sep 20, 2026
8Partial evidenceBaltimore, MD, United StatesHQ checked Sep 20, 2026n/a1,255 contacts →

Partial evidence

“TBC is an independently owned, full-service branding, advertising and strategic communications agency with headquarters in Baltimore, Maryland, USA.”

Source: RevenueBase Database · checked Sep 20, 2026
9Indirect evidenceMinato-ku, United StatesHQ checked Sep 20, 20261,001-5,0001,168 contacts →

Indirect evidence

“Founded in 1895, Hakuhodo Inc.”

Source: RevenueBase Database · checked Sep 20, 2026
10Partial evidenceStockport, United KingdomHQ checked Sep 20, 2026501-1,0001,152 contacts →

Partial evidence

“We’ve been delivering marketing and communications since 1961.”

Source: RevenueBase Database · checked Sep 20, 2026
11Indirect evidenceSão Paulo, BrazilHQ checked Sep 20, 20261,001-5,000963 contacts →

Indirect evidence

“Media.Monks, the digital-first operating brand of S4Capital plc, connects content, data & digital media and technology services across one global team built from the bottom up.”

Source: RevenueBase Database · checked Sep 20, 2026
12Indirect evidenceHamburg, GermanyHQ checked Sep 20, 20261,001-5,000944 contacts →

Indirect evidence

“Scholz & Friends provides an all-inclusive selection of resources to assist client partners in sharing their stories and ideas.”

Source: RevenueBase Database · checked Sep 20, 2026
13Indirect evidenceNew York, NY, United StatesHQ checked Sep 20, 20261,001-5,000903 contacts →

Indirect evidence

“1300+ People.”

Source: RevenueBase Database · checked Sep 20, 2026
14Partial evidenceNew York, NY, United StatesHQ checked Sep 20, 2026501-1,000887 contacts →

Partial evidence

“Zeno Group is the fiercely independent and global, integrated communications agency, born from PR.”

Source: RevenueBase Database · checked Sep 20, 2026
15Partial evidenceNew York, NY, United StatesHQ checked Sep 20, 2026n/a872 contacts →

Partial evidence

“We are a full-service communications agency behind some of the world’s most revered and iconic brands.”

Source: RevenueBase Database · checked Sep 20, 2026
16Indirect evidenceChemnitz, GermanyHQ checked Sep 20, 2026501-1,000859 contacts →

Indirect evidence

“Staffbase is the first AI-native Employee Experience Platform, equipping many of the world’s leading companies with solutions to inspire every employee with motivating…”

Source: RevenueBase Database · checked Sep 20, 2026
17Partial evidenceMumbai, IndiaHQ checked Sep 20, 2026201-500851 contacts →

Partial evidence

“MullenLowe Lintas Group is one of India’s largest and most admired communication groups.”

Source: RevenueBase Database · checked Sep 20, 2026
18Indirect evidenceCaracas, VenezuelaHQ checked Sep 20, 20261,001-5,000816 contacts →

Indirect evidence

“Responsable de actividades de Mercadeo, Publicidad, Comunicaciones Corporativas, Calidad y Gestión Comercial de la Red de 122 agencias a Nivel Nacional.”

Source: RevenueBase Database · checked Sep 20, 2026
19Partial evidenceNew York, NY, United StatesHQ checked Sep 20, 20261,001-5,000815 contacts →

Partial evidence

“Ruder Finn is one of the world’s largest global independent integrated marketing and communications agencies, leading at the intersection of technology, human creativity, and…”

Source: RevenueBase Database · checked Sep 20, 2026
20Partial evidenceSydney, AustraliaHQ checked Sep 20, 2026n/a621 contacts →

Partial evidence

“JIMJAM Ideas is an award winning integrated communications agency that believes CONNECTED IDEAS to be the key to powerful and transformative marketing.”

Source: RevenueBase Database · checked Sep 20, 2026
21Indirect evidenceSao Paulo, BrazilHQ checked Sep 20, 2026501-1,000600 contacts →

Indirect evidence

“A BETC foi fundada em Paris em 1994 e segue sendo reconhecida como uma das agências mais criativas e premiadas do mundo.”

Source: RevenueBase Database · checked Sep 20, 2026
22Partial evidenceLondon, United KingdomHQ checked Sep 20, 2026501-1,000550 contacts →

Partial evidence

“We are Grayling, the world's local communications agency.”

Source: RevenueBase Database · checked Sep 20, 2026
23Indirect evidenceLondon, United KingdomHQ checked Sep 20, 20261,001-5,000544 contacts →

Indirect evidence

“Happy to see you came here to learn a little more about us!”

Source: RevenueBase Database · checked Sep 20, 2026
24Indirect evidenceNew York, NY, United StatesHQ checked Sep 20, 2026201-500543 contacts →

Indirect evidence

“Prosek Partners builds – and protects – the top brands in business.”

Source: RevenueBase Database · checked Sep 20, 2026
25Indirect evidenceAtlanta, GA, United StatesHQ checked Sep 20, 2026n/a527 contacts →

Indirect evidence

“Everywhere Agency is now a part of MWWPR.”

Source: RevenueBase Database · checked Sep 20, 2026

Showing 25 of 26,030 internal communications agencies worldwide

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Internal communications agencies worldwide at a glance

As of Sep 20, 2026
23.4%Verified-email coverage
11.9Average contacts per company
1-10Median size (employees)
2.7%Largest-city concentration · Sao Paulo
Sep 20, 2026Page data refreshed

Companies by employee count

1-10
16,621
11-50
7,543
51-200
1,391
201-500
258
501-1,000
89
1,001-5,000
60
5,001-10,000
7
10001+
18

Email recency is reported on each country list linked below.

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 agencies, 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.
Coverage
Every country. Country and city lists for internal communications agencies are linked below.
What qualifies
Companies worldwide whose own description of what they do matches “internal communications agencies”. 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 agencies), 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 agencies, and records with no verified work email.
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, 72,520 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 20, 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.

Internal communications agencies by location

117 lists · largest first

Every Internal communications agencies list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.

Countries

Cities

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 agencies, 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 agencies are there worldwide?

RevenueBase identified 26,030 internal communications agencies worldwide 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?

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

Which country has the most internal communications agencies?

The United States leads with 2,570 companies, followed by Brazil (2,433) and France (2,057). Every internal communications agencies list by country and city is linked on this page.

Which city has the most internal communications agencies?

Sao Paulo leads with 707 headquartered companies, followed by London (605) and Paris (477).

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 72,520 verified decision-maker contacts tracked across these 26,030 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 20, 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.