Company lists · Data refreshed September 2026
Top 25 Contact center consulting firms based in London, United Kingdom
RevenueBase identified 167 contact center consulting firms headquartered in London, United Kingdom as of September 2026 and tracks 2,675 professional contacts across them, including 485 with verified work emails. Across the United Kingdom, London is the largest hub for this category.
This list covers contact center consulting firms 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 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 contact center consulting firms based in London, United Kingdom
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 569 contacts → | ||||
Indirect evidence “Vertex is a leader in BPO and Customer Management Outsourcing, serving over 200 clients worldwide across many sectors.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 2 | 302 contacts → | ||||
Partial 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 27, 2026Thanks. The Data Team will review it. | |||||
| 3 | 98 contacts → | ||||
Strong evidence “Founded in 1988, RSVP is the oldest provider of contact centre services in the UK.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 4 | 96 contacts → | ||||
Indirect evidence “We’re service communication experts – using a mix of science, creativity and service know-how to improve how you talk with your customers through all channels and media, from…” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 5 | 90 contacts → | ||||
Indirect evidence “A world class offshore outsourcing agency, with offices in London and Harare, we have access to some of the best educated, best spoken graduates you will find anywhere in the…” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 6 | 63 contacts → | ||||
Strong evidence “Business Systems is a trusted transformation partner with over 35 years of experience helping CX teams and contact centres become smarter, faster and more compliant.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 7 | 59 contacts → | ||||
Strong evidence “CallCare is your outsourced contact centre and customer service partner.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 8 | 51 contacts → | ||||
Indirect evidence “For nearly 4 decades, we have worked with some of the world’s best brands to design and enable great customer experiences.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 9 | 49 contacts → | ||||
Indirect 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. | |||||
| 10 | 46 contacts → | ||||
Strong evidence “Direct Response can provide outsourcing of voice, data and contact centre services for organisation from a global business to a one-man operation, delivering outstanding service…” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 11 | 40 contacts → | ||||
Indirect evidence “Kingdom Vision is a medium to take your business from good to great.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 12 | 35 contacts → | ||||
Indirect evidence “Market Intelligence International (Marketii) is a trusted advisor to the world’s leading organizations in technology, medical devices, and consumer products.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 13 | 33 contacts → | ||||
Strong evidence “For more than 30 years, the CCMA has been dedicated to supporting contact centre leaders.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 14 | 33 contacts → | ||||
Indirect evidence “KPMG Nunwood specialises in customer experience improvement.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 15 | 32 contacts → | ||||
Partial evidence “StableLogic is a technology consultancy specialising in customer contact, networking, software development and cloud expertise.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 16 | 28 contacts → | ||||
Indirect evidence “Our customer service outsourcing and software solutions create happier customers, happier customer service agents, and save you money.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 17 | 24 contacts → | ||||
Indirect evidence “We are here to help global enterprises design, build and scale up their customer experience programs.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 18 | 22 contacts → | ||||
Partial evidence “We are a consulting & technology company with expertise across Consumer, B2B and Health.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 19 | 16 contacts → | ||||
Indirect evidence “Horizon Strategy is a consultancy whose mission is to reinvent and democratise strategic advice.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 20 | 13 contacts → | ||||
Indirect evidence “At Refractis we believe that technology done well can change an organisation, enhancing customer interactions, delivering new insights and optimising business operations.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 21 | 12 contacts → | ||||
Partial evidence “Whilst Equantiis is no more, the fabulous consulting team are now in Spherica Consulting.” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 22 | 9 contacts → | ||||
Partial evidence “Based in the UK, Voxal is a consulting company delivering management and customer experience (strategy advice, training, measurement, data analysis) consulting services to…” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 23 | 7 contacts → | ||||
Indirect evidence “At alaouico, we understand the challenges businesses face with customer interactions-whether it's managing high call volumes, ensuring timely responses, or maintaining customer…” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 24 | 6 contacts → | ||||
Indirect evidence “We are assisting our customers to become market leaders in various domains particularly sales, crm risk and fraud management using unique combination of specific business know…” Source: RevenueBase Database · checked Sep 27, 2026Thanks. The Data Team will review it. | |||||
| 25 | 6 contacts → | ||||
Indirect evidence “Insight Now are the experts in delivering improved operational efficiency & customer experience across your customer service channels.” 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: contact center 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 contact center consulting firms.
- Partial evidence
- Its own public description names part of contact center consulting firms, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name contact center 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 167 contact center consulting firms based in London, United Kingdom
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Contact center consulting firms based in London, United Kingdom at a glance
As of Sep 27, 2026Companies by employee count
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 167 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 contact center 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 London, United Kingdom whose own description of what they do matches “contact center 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 contact center 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 contact center consulting firms, 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, 485 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.
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 contact center 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 contact center consulting firms are there based in London, United Kingdom?
RevenueBase identified 167 contact center consulting firms 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?
Vertex Data Science, headquartered in London, tops this list with the largest team on record.
Which city in the United Kingdom has the most contact center consulting firms?
London leads the United Kingdom with 167 headquartered companies, followed by Manchester (18) and Bristol (12).
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 485 verified decision-maker contacts tracked across these 167 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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