Company lists · Data refreshed September 2026

Top 24 B2B consultancy services based in London, United Kingdom

RevenueBase identified 3,408 B2B consultancy services headquartered in London, United Kingdom as of September 2026 and tracks 43,322 professional contacts across them, including 18,737 with verified work emails. London is the largest hub.

This list covers B2B consultancy services headquartered in London, United Kingdom, 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 23, 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 23, 2026 86% judged on-target in blind review
3,408Companies
43,322Contacts tracked
18,737Verified emails
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The 24 largest B2B consultancy services based in London, United Kingdom

Ranked by team size
Top 24 of 3,408 B2B consultancy services based in London, United Kingdom, ranked by team size, largest first. Data refreshed Sep 23, 2026. RevenueBase Smart Search rates how each company's information relates to B2B consultancy services: 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 evidenceLondon, United KingdomHQ checked Sep 23, 202610001+17,070 contacts →

Indirect evidence

“Our unique combination of transformative strategy, transactions and corporate finance delivers real-world value – solutions that work in practice, not just on paper.”

Source: RevenueBase Database · checked Sep 23, 2026
2Indirect evidenceLondon, United KingdomHQ checked Sep 23, 20261,001-5,0002,179 contacts →

Indirect evidence

“Baringa is a global consulting firm that helps leaders drive meaningful change and create value.”

Source: RevenueBase Database · checked Sep 23, 2026
3Partial evidenceLondon, United KingdomHQ checked Sep 23, 2026501-1,0001,011 contacts →

Partial evidence

“At OC & C Strategy Consultants we have more than 35 years of experience at unpicking the most complex business challenges with simple, uncommon sense™.”

Source: RevenueBase Database · checked Sep 23, 2026
4Indirect evidenceLondon, United KingdomHQ checked Sep 23, 2026501-1,000408 contacts →

Indirect evidence

“Zenitech creates technology to transform businesses.”

Source: RevenueBase Database · checked Sep 23, 2026
5Indirect evidenceLondon, United KingdomHQ checked Sep 23, 2026501-1,000333 contacts →

Indirect evidence

“Ubique Systems is a fast growing multifaceted organization which offers a comprehensive array of outsourcing and consulting services for its customers, including recruitment…”

Source: RevenueBase Database · checked Sep 23, 2026
6Indirect evidenceLondon, United KingdomHQ checked Sep 23, 20265,001-10,000329 contacts →

Indirect evidence

“We are the global consulting division of Davies, accelerating business, technology and people performance across financial services including Retail Finance & Corporate Banking…”

Source: RevenueBase Database · checked Sep 23, 2026
7Indirect evidenceLondon, United KingdomHQ checked Sep 23, 2026201-500302 contacts →

Indirect evidence

“Cartesian is a specialist consulting firm focused on the global telecommunications, media, and technology industries and is now part of Bounteous, an AI services firm helping…”

Source: RevenueBase Database · checked Sep 23, 2026
8Indirect evidenceLondon, United KingdomHQ checked Sep 23, 2026501-1,000275 contacts →

Indirect evidence

“An award-winning global consulting firm working with clients across a diverse range of markets, industries and geographies.”

Source: RevenueBase Database · checked Sep 23, 2026
9Indirect evidenceLondon, United KingdomHQ checked Sep 23, 2026201-500255 contacts →

Indirect evidence

“Transform is a fresh alternative to Big Consulting.”

Source: RevenueBase Database · checked Sep 23, 2026
10Indirect evidenceLondon, United KingdomHQ checked Sep 23, 2026201-500247 contacts →

Indirect evidence

“We’re a dynamic consulting firm, focused on delivering change.”

Source: RevenueBase Database · checked Sep 23, 2026
11Partial evidenceLondon, United KingdomHQ checked Sep 23, 2026201-500245 contacts →

Partial evidence

“Percipere is a niche global consultancy, partnering companies in their evolution towards greater operational efficiency and profitability.”

Source: RevenueBase Database · checked Sep 23, 2026
12Indirect evidenceLondon, United KingdomHQ checked Sep 23, 2026201-500240 contacts →

Indirect evidence

“Albany Beck is a client-first consulting firm helping financial services organisations deliver complex change and build capability, not dependency.”

Source: RevenueBase Database · checked Sep 23, 2026
13Indirect evidenceLondon, United KingdomHQ checked Sep 23, 2026201-500216 contacts →

Indirect evidence

“Quantzig is at the forefront of partnering with businesses to help them unlock transformative value through analytics solutions.”

Source: RevenueBase Database · checked Sep 23, 2026
14Indirect evidenceLondon, United KingdomHQ checked Sep 23, 2026201-500192 contacts →

Indirect evidence

“AbsoluteLabs is a Salesforce Summit Partner and partner of Microsoft Azure, Amazon Web Services, and Google Cloud Platform.”

Source: RevenueBase Database · checked Sep 23, 2026
15Indirect evidenceLondon, United KingdomHQ checked Sep 23, 2026201-500178 contacts →

Indirect evidence

“The future has never moved this fast.”

Source: RevenueBase Database · checked Sep 23, 2026
16Partial evidenceLondon, United KingdomHQ checked Sep 23, 202651-200170 contacts →

Partial evidence

“We are an employee-owned, award-winning international consulting firm that believes there’s a better way to do consultancy.”

Source: RevenueBase Database · checked Sep 23, 2026
17Partial evidenceLondon, United KingdomHQ checked Sep 23, 20265,001-10,000167 contacts →

Partial evidence

“BIP is the international consultancy for the 21st century with over 6,500 consultants globally daring to make a difference.”

Source: RevenueBase Database · checked Sep 23, 2026
18Indirect evidenceLondon, United KingdomHQ checked Sep 23, 2026n/a165 contacts →

Indirect evidence

“Strategic development for already dynamic businesses, successful mergers & acquisitions between household names, technology planning in cutting edge industries and real-world…”

Source: RevenueBase Database · checked Sep 23, 2026
19Indirect evidenceLondon, United KingdomHQ checked Sep 23, 202651-200160 contacts →

Indirect evidence

“InterEx Group is becoming the strategic partner of choice for organizations undergoing digital, business, and technology transformation.”

Source: RevenueBase Database · checked Sep 23, 2026
20Partial evidenceLondon, United KingdomHQ checked Sep 23, 202651-200152 contacts →

Partial evidence

“Founded in 1990, The Berkeley Partnership is an independent management consultancy, specialising in business transformation.”

Source: RevenueBase Database · checked Sep 23, 2026
21Indirect evidenceLondon, United KingdomHQ checked Sep 23, 20261,001-5,000139 contacts →

Indirect evidence

“We believe that change is an opportunity to thrive.”

Source: RevenueBase Database · checked Sep 23, 2026
22Partial evidenceLondon, United KingdomHQ checked Sep 23, 202651-200139 contacts →

Partial evidence

“Publicis Pro is the specialist B2B marketing agency within Publicis Groupe, the world's number one marketing holding group.”

Source: RevenueBase Database · checked Sep 23, 2026
23Partial evidenceLondon, United KingdomHQ checked Sep 23, 202651-200134 contacts →

Partial evidence

“Winners of the UKOUG Business Transformation Advisory Partner of the Year Award 2025 Veran Performance is an advisory consultancy specialising in HR, Payroll, Procurement and…”

Source: RevenueBase Database · checked Sep 23, 2026
24Indirect evidenceLondon, United KingdomHQ checked Sep 23, 202611-50122 contacts →

Indirect evidence

“Athens helps clients make superior investment decisions and supports them to deliver value from these decisions through timely implementation.”

Source: RevenueBase Database · checked Sep 23, 2026

Showing 24 of 3,408 B2B consultancy services based in London, United Kingdom

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B2B consultancy services based in London, United Kingdom at a glance

As of Sep 23, 2026
43.3%Verified-email coverage
12.7Average contacts per company
1-10Median size (employees)
100.0%Largest-city concentration · London
Sep 23, 2026Page data refreshed

Companies by employee count

1-10
2,552
11-50
620
51-200
161
201-500
35
501-1,000
8
1,001-5,000
12
5,001-10,000
6
10001+
5

Email recency for this list is measured across the whole United Kingdom list rather than for London, so it is reported there. Company counts and contact totals on this page are exact for London, over 3,408 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 B2B consultancy services, 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 London, United Kingdom whose own description of what they do matches “B2B consultancy services”. 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 B2B consultancy services), 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 B2B consultancy services, and records with no verified work email. Companies headquartered outside London 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, 18,737 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 23, 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 B2B consultancy services, 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 B2B consultancy services are there based in London, United Kingdom?

RevenueBase identified 3,408 B2B consultancy services headquartered in London, United Kingdom 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?

Ey-Parthenon, headquartered in London, tops this list with the largest team on record.

Which city has the most B2B consultancy services?

London leads with 3408 headquartered companies, followed by Manchester (211) and Birmingham (121).

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 18,737 verified decision-maker contacts tracked across these 3,408 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 23, 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.