Company lists · Data refreshed October 2026

Top 25 Internal marketing agencies worldwide

RevenueBase identified 143,459 internal marketing agencies worldwide as of October 2026 and tracks 987,269 professional contacts across them, including 254,149 with verified work emails and 175,921 with mobile numbers. The United States is the largest market and London the largest hub.

This list covers internal marketing 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 October 1, 2026. Country and city lists for internal marketing 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 Oct 1, 2026 86% judged on-target in blind review
143,459Companies
987,269Contacts tracked
254,149Verified emails
175,921Mobile numbers
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The 25 largest internal marketing agencies worldwide

Ranked by team size
Top 25 of 143,459 internal marketing agencies worldwide, ranked by team size, largest first. Data refreshed Oct 1, 2026. RevenueBase Smart Search rates how each company's information relates to internal marketing 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
1Indirect evidenceUsa, FranceHQ checked Oct 1, 202610001+7,716 contacts →

Indirect evidence

“At Deloitte Digital, we connect brands with the right strategies and tools to create great impact.”

Source: RevenueBase Database · checked Oct 1, 2026
2Indirect evidencePrague, United KingdomHQ checked Oct 1, 202610001+5,483 contacts →

Indirect evidence

Source: RevenueBase Database · checked Oct 1, 2026
3Partial evidenceNew York, NY, United StatesHQ checked Oct 1, 202610001+4,963 contacts →

Partial evidence

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

Source: RevenueBase Database · checked Oct 1, 2026
4Indirect evidenceLondon, United KingdomHQ checked Oct 1, 202610001+3,692 contacts →

Indirect evidence

“We discover the breakthroughs that brands need to win.”

Source: RevenueBase Database · checked Oct 1, 2026
5Partial evidenceHerentals, BelgiumHQ checked Oct 1, 20261,001-5,0003,670 contacts →

Partial evidence

“iO is an AI-native partner in marketing and technology, with experts across 12 campuses in Belgium, the Netherlands, Sweden, Denmark and Bulgaria.”

Source: RevenueBase Database · checked Oct 1, 2026
6Indirect evidenceBoston, MA, United StatesHQ checked Oct 1, 20261,001-5,0002,654 contacts →

Indirect evidence

“Digitas is the Networked Experience Agency, built on the vision that we create magnetic experiences that earn the right for brands to exist in human networks.”

Source: RevenueBase Database · checked Oct 1, 2026
7Indirect evidenceNew York, NY, United StatesHQ checked Oct 1, 20261,001-5,0002,368 contacts →

Indirect evidence

“Horizon Media is a leader in driving business-based outcomes for marketers.”

Source: RevenueBase Database · checked Oct 1, 2026
8Indirect evidenceLondon, United KingdomHQ checked Oct 1, 20265,001-10,0002,366 contacts →

Indirect evidence

“iProspect, a dentsu company, is a leading global digital-first media agency.”

Source: RevenueBase Database · checked Oct 1, 2026
9Indirect evidenceNew York, NY, United StatesHQ checked Oct 1, 20261,001-5,0001,763 contacts →

Indirect evidence

“Hi there!”

Source: RevenueBase Database · checked Oct 1, 2026
10Partial evidenceNew York, NY, United StatesHQ checked Oct 1, 202610001+1,727 contacts →

Partial evidence

“Omnicom is the world’s leading marketing and sales company, built for intelligent growth in the next era.”

Source: RevenueBase Database · checked Oct 1, 2026
11Indirect evidenceGranada, MexicoHQ checked Oct 1, 2026n/a1,672 contacts →

Indirect evidence

“Tal vez algunos nos conozcan por la terraza donde muchos han venido a chelear con nosotros algún jueves.”

Source: RevenueBase Database · checked Oct 1, 2026
12Partial evidenceNew York, NY, United StatesHQ checked Oct 1, 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 Oct 1, 2026
13Indirect evidenceMadrid, SpainHQ checked Oct 1, 20261,001-5,0001,520 contacts →

Indirect evidence

“Together, we enhance and protect the value of your business.”

Source: RevenueBase Database · checked Oct 1, 2026
14Indirect evidenceLondon, United StatesHQ checked Oct 1, 20265,001-10,0001,451 contacts →

Indirect evidence

“We are Wunderman, a global digital agency that is 'Creatively Driven.”

Source: RevenueBase Database · checked Oct 1, 2026
15Indirect evidenceNew York, NY, United StatesHQ checked Oct 1, 202610001+1,207 contacts →

Indirect evidence

“We build enduring brands that move people and markets through the radical creativity of Truth Well Told™.”

Source: RevenueBase Database · checked Oct 1, 2026
16Partial evidenceStockport, United KingdomHQ checked Oct 1, 2026501-1,0001,152 contacts →

Partial evidence

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

Source: RevenueBase Database · checked Oct 1, 2026
17Indirect evidenceSão Paulo, BrazilHQ checked Oct 1, 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 Oct 1, 2026
18Indirect evidenceLondon, United KingdomHQ checked Oct 1, 20265,001-10,000941 contacts →

Indirect evidence

“Welcome to dentsu X.”

Source: RevenueBase Database · checked Oct 1, 2026
19Indirect evidenceMadrid, SpainHQ checked Oct 1, 2026n/a927 contacts →

Indirect evidence

“Super no es una multinacional, ¡Viva la independencia!”

Source: RevenueBase Database · checked Oct 1, 2026
20Indirect evidenceNew York, NY, United StatesHQ checked Oct 1, 20261,001-5,000903 contacts →

Indirect evidence

“1300+ People.”

Source: RevenueBase Database · checked Oct 1, 2026
21Indirect evidencePantin, FranceHQ checked Oct 1, 2026501-1,000869 contacts →

Indirect evidence

“BETC, agence de communication créée en 1994, renouvelle le rapport entre les marques et la création.”

Source: RevenueBase Database · checked Oct 1, 2026
22Indirect evidenceSan Diego, CA, United StatesHQ checked Oct 1, 20261,001-5,000866 contacts →

Indirect evidence

“Neil Patel has been recognized by the Wall Street Journal, Forbes, and the United Nations, to name a few, as one of the most influential and successful marketers and entrepreneurs…”

Source: RevenueBase Database · checked Oct 1, 2026
23Partial evidenceSydney, AustraliaHQ checked Oct 1, 20261,001-5,000860 contacts →

Partial evidence

“IVE Group is Australia’s largest diversified marketing company.”

Source: RevenueBase Database · checked Oct 1, 2026
24Indirect evidenceLondon, United KingdomHQ checked Oct 1, 2026501-1,000820 contacts →

Indirect evidence

“VCCP is the global challenger network for challenger brands.”

Source: RevenueBase Database · checked Oct 1, 2026
25Indirect evidenceLeeds, United KingdomHQ checked Oct 1, 2026n/a811 contacts →

Indirect evidence

“Uber means over, above more than.”

Source: RevenueBase Database · checked Oct 1, 2026

Showing 25 of 143,459 internal marketing agencies worldwide

See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 254,149 reachable decision-makers.

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Internal marketing agencies worldwide at a glance

As of Oct 1, 2026
25.7%Verified-email coverage
17.8%Mobile-number coverage
6.9Average contacts per company
1-10Median size (employees)
3.3%Largest-city concentration · London
Oct 1, 2026Page data refreshed

Companies by employee count

1-10
109,053
11-50
29,604
51-200
3,709
201-500
618
501-1,000
141
1,001-5,000
95
5,001-10,000
17
10001+
48

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 marketing 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
43 countries, largest first: the United States, the United Kingdom, Brazil, Canada, Australia, Spain, Italy, Mexico, the Netherlands, France and 33 more. Country and city lists for internal marketing agencies are linked below.
What qualifies
Companies worldwide whose own description of what they do matches “internal marketing 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 marketing 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 marketing 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, 254,149 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 October 1, 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 marketing agencies by location

310 lists · largest first

Every Internal marketing 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 marketing 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 marketing agencies are there worldwide?

RevenueBase identified 143,459 internal marketing agencies worldwide as of October 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?

Deloitte Digital, headquartered in Canberra, tops this list with the largest team on record.

Which country has the most internal marketing agencies?

The United States leads with 52,536 companies, followed by the United Kingdom (14,287) and Brazil (13,820). Every internal marketing agencies list by country and city is linked on this page.

Which city has the most internal marketing agencies?

London leads with 4741 headquartered companies, followed by Sao Paulo (3070) and New York (2838).

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 254,149 verified decision-maker contacts tracked across these 143,459 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on October 1, 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.