Company lists · Data refreshed September 2026
Top 25 Client success consulting firms based in the United Kingdom
RevenueBase identified 2,354 client success consulting firms headquartered in the United Kingdom as of September 2026 and tracks 18,866 professional contacts across them, including 5,723 with verified work emails. London is the largest hub.
This list covers client success consulting firms headquartered in the 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 27, 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.
The 25 largest client success consulting firms based in the United Kingdom
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 2,179 contacts → | ||||
Partial evidence “Baringa is a global consulting firm that helps leaders drive meaningful change and create value.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 2 | 1,361 contacts → | ||||
Indirect evidence “As of April 1, 2019, JLT Group is now part of Marsh & McLennan Companies (MMC).” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 3 | 1,011 contacts → | ||||
Indirect 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 27, 2026Thanks. The Data Team will review it. | |||||
| 4 | 329 contacts → | ||||
Partial evidence “At Mercer, A Marsh business, we’re helping our clients realize their investment objectives, shape the future of work, and enhance health and retirement outcomes for their people.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 5 | 275 contacts → | ||||
Strong evidence “An award-winning global consulting firm working with clients across a diverse range of markets, industries and geographies.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 6 | 247 contacts → | ||||
Partial evidence “We’re a dynamic consulting firm, focused on delivering change.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 7 | 216 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 27, 2026Thanks. The Data Team will review it. | |||||
| 8 | 191 contacts → | ||||
Partial evidence “Clarify helps global Technology companies achieve sustained and significant commercial success.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 9 | 139 contacts → | ||||
Indirect evidence “We believe that change is an opportunity to thrive.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 10 | 75 contacts → | ||||
Strong evidence “We redefined management consulting to make it better for clients and better for consultants.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 11 | 72 contacts → | ||||
Partial evidence “Excalibur provides an end to end business consulting service that offers reliable insight, and expertise in communications and technology.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 12 | 69 contacts → | ||||
Indirect evidence “In complex transformation programmes, risk, regulation, financial crime, data, technology and operations no longer sit in separate silos.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 13 | 66 contacts → | ||||
Indirect evidence “We are a network of independent consultants who are ex-C-Suite Execs/Senior Managers who have all been there and done it in top organisations, mainly in insurance but others as…” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 14 | 63 contacts → | ||||
Indirect evidence “LTK are a outsourced solutions provider, assisting you to reach your goals through customer retention, sales growth, business & strategy development/ implementation and people…” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 15 | 59 contacts → | ||||
Indirect evidence “We’re people-first and culture-obsessed.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 16 | 59 contacts → | ||||
Indirect evidence “Consult us for.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 17 | 54 contacts → | ||||
Partial evidence “At ModernLogic we believe that the customer journey should not end with a successful implementation.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 18 | 53 contacts → | ||||
Indirect evidence “Passle powers growth at the world's leading professional services firms, including Ropes & Gray, Linklaters, Quinn Emanuel and many more.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 19 | 51 contacts → | ||||
Partial evidence “QA Consulting is a leading provider of consulting services to commercial, financial organisations and government departments.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 20 | 50 contacts → | ||||
Partial evidence “Collinson Grant helps clients throughout the world to improve efficiency and profitability.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 21 | 49 contacts → | ||||
Partial evidence “Since we’ve helped ambitious leaders and organisations create true customer-led success.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 22 | 41 contacts → | ||||
Indirect evidence “You can now find us over at EPAM Continuum.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 23 | 40 contacts → | ||||
Indirect evidence “Global leaders in strategy execution.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 24 | 38 contacts → | ||||
Partial evidence “At Regency Grove we pride ourselves on providing each client with an exceptional standard of service to suit their specific needs and requirements.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 25 | 38 contacts → | ||||
Partial evidence “Partners in Change Consulting is here to help you and your organisation get change done.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
RevenueBase Smart Search
RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: client success consulting firms. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.
- Strong evidence
- The company's own public description of its business names client success consulting firms.
- Partial evidence
- Its own public description names part of client success consulting firms, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name client success consulting firms. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.
RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.
Showing 25 of 2,354 client success consulting firms based in the United Kingdom
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Client success consulting firms based in the United Kingdom at a glance
As of Sep 27, 2026Companies by employee count
Email recency for this list is measured worldwide rather than for United Kingdom, so it is reported there. Company counts and contact totals on this page are exact for United Kingdom, over 2,354 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 client success consulting firms, 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 Kingdom whose own description of what they do matches “client success consulting firms”. 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 client success consulting firms), 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 client success consulting firms, and records with no verified work email. Companies headquartered outside United Kingdom 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, 5,723 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 27, 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.
Client success consulting firms by metro
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 client success consulting firms, 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 client success consulting firms are there based in the United Kingdom?
RevenueBase identified 2,354 client success consulting firms headquartered in the 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?
Baringa, headquartered in London, tops this list with the largest team on record.
Which city has the most client success consulting firms?
London leads with 846 headquartered companies, followed by Manchester (55) and Bristol (26).
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 5,723 verified decision-maker contacts tracked across these 2,354 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 27, 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.
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