Company lists · Data refreshed November 2026

Top 15 IT system integrators based in London, United Kingdom

RevenueBase identified 151 company matches for IT system integrators associated with London, United Kingdom as of November 2026 and tracks 2,823 professional contacts across them, including 1,254 with verified work emails. Across the United Kingdom, London is the largest hub for this category.

This list covers company matches for IT system integrators associated with London, United Kingdom, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed November 6, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, 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 RevenueBase SmartSearch · Exact Recorded Nov 6, 2026 How this list was built
151Companies
2,823Contacts tracked
1,254Verified emails
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The 15 largest IT system integrators based in London, United Kingdom

Ranked by team size
Top 15 of 151 company matches for IT system integrators based in London, United Kingdom, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Nov 6, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#CompanyRevenueBase SmartSearchHeadquartersEmployeesContacts
1Exact matchLondon, United KingdomHQ recorded Nov 6, 202651-200128 contacts →

Exact match

“OpticoreIT is an IT Consultancy founded in 2013 to bridge a gap in the market between the major IT services providers and the consultancy market.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
2Exact matchLondon, United KingdomHQ recorded Nov 6, 202651-20083 contacts →

Exact match

“Nephos Technologies is an independent data systems integrator, specialising in helping organisations transform the way they store, manage and protect their data.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
3Exact matchLondon, United KingdomHQ recorded Nov 6, 202651-20057 contacts →

Exact match

“We are the trusted IT integrator that specialises in making your work flow.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
4Exact matchLondon, United KingdomHQ recorded Nov 6, 202651-20053 contacts →

Exact match

“Diegesis is a business technology and IT systems integration company that specialises in Decision Support Solutions.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
5Exact matchLondon, United KingdomHQ recorded Nov 6, 202651-20048 contacts →

Exact match

“Pace Integration is a unique technology consultancy that solves your integration challenge – focused on enterprise systems integration strategy, architecture and design that is…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
6Exact matchLondon, United KingdomHQ recorded Nov 6, 202611-5042 contacts →

Exact match

“R3 Digital is a Systems Integrator and Salesforce Platinum (Summit) Consulting Partner that specialises in Health and Life Sciences.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
7Exact matchLondon, United KingdomHQ recorded Nov 6, 202611-5041 contacts →

Exact match

“For over thirty years, OKTO has designed, built and commissioned the technology inside buildings where failure has consequences.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
8Exact matchLondon, United KingdomHQ recorded Nov 6, 202611-5039 contacts →

Exact match

“MiX is an independent consultancy specialising in IT Infrastructure, Communication, Data Centre, Audio Visual, Physical Security & SMART Buildings Technology Solutions.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
9Exact matchLondon, United KingdomHQ recorded Nov 6, 202611-5028 contacts →

Exact match

“BestPath provides next generation, easy to use IT solutions for businesses of all sizes, from FTSE 100 companies to start-ups.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
10Exact matchLondon, United KingdomHQ recorded Nov 6, 202611-5027 contacts →

Exact match

“Principle Networks works with commercial and regulated organisations to reduce cyber risk and cost by simplifying security and network architecture.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
11Exact matchLondon, United KingdomHQ recorded Nov 6, 20261,001-5,00023 contacts →

Exact match

“IGXGlobal is a technology systems integrator at the forefront of digital transformation.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
12Exact matchLondon, United KingdomHQ recorded Nov 6, 202651-20019 contacts →

Exact match

“Welcome to Kumoco.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
13Exact matchLondon, United KingdomHQ recorded Nov 6, 202611-5017 contacts →

Exact match

“Empowering Your Business with Expert IT Solutions We deliver Services across Enterprise Data Centres offering an Enterprise Service to ITIL standards.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
14Exact matchLondon, United KingdomHQ recorded Nov 6, 202651-20017 contacts →

Exact match

Recorded description not available.

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
15Exact matchLondon, United KingdomHQ recorded Nov 6, 202651-20015 contacts →

Exact match

“A3 & O, the leading telecommunication System Integrator and Solution Provider; The company provides state of the art technologies and turnkey solutions to its clients across the…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase

Showing 15 of 151 IT system integrators based in London, United Kingdom

See the full list, filter by size, metro and specialty, and access 1,254 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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IT system integrators based in London, United Kingdom at a glance

As of Nov 6, 2026
44.4%Verified-email coverage
18.7Average contacts per company
1-10Median size (employees)
Nov 6, 2026Page data refreshed

Companies by employee count

1-10
75
11-50
42
51-200
24
201-500
5
501-1,000
2
1,001-5,000
2

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 151 companies.

How this list was built

The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.

Source
The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase SmartSearch, the natural-language company search available to every RevenueBase user.
What qualifies
Company records associated with London, United Kingdom whose business descriptions match “IT system integrators” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
RevenueBase SmartSearch
Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
Public preview
The public preview omits records without a verified work email. Where headquarters information is recorded, preview rows are also filtered to this page’s location. Dataset totals and geographic summaries describe the full matched records before these preview filters.
Match quality
RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
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 displayed company carries at least one verified work email. RevenueBase tracks 1,254 professional contacts with verified work emails across the full matched dataset. 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 November 6, 2026. Lists refresh periodically as the graph is re-checked.
Record context
Company records and descriptions can change. Check the company's website for its current services and locations.

Frequently asked

What is RevenueBase SmartSearch?

RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “IT system integrators”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many IT system integrators are there based in London, United Kingdom?

RevenueBase identified 151 company matches for IT system integrators associated with London, United Kingdom as of November 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.

What is the largest company on this list?

Opticoreit tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city in the United Kingdom has the most IT system integrators?

London leads the United Kingdom with 151 company records, followed by Manchester (22) and Bristol (16).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 1,254 professional contacts with verified work emails tracked across these 151 companies; direct dials are available where recorded.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on November 6, 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 SmartSearch, 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.