The companies listed here are large managed service providers headquartered in the United Kingdom. They mostly offer IT services and consulting, with a significant presence in telecommunications. FUJITSU, a global information and communication technology company, is the largest. Computacenter helps large organizations manage and transform their technology infrastructure, while Iron Mountain EMEA specializes in storage and information management services. SCC provides limitless IT solutions, including cybersecurity and digital workplace services. Vodafone Business offers mobile, fixed, unified communications, IoT, cloud, and security services.
A notable pattern among these companies is the concentration of headquarters in London, with several other significant presences in cities like Hatfield, Birmingham, and Warwick. This indicates a strong hub for managed IT and telecommunications services within the UK.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 |
FUJITSUglobal.fujitsu
Leading global information and communication technology company, offering technology products, solutions, and services, connecting people, technology, and ideas for a sustainable world. |
124,000 | |||
| 2 |
Computacentercomputacenter.com
A leading technology and services provider, trusted by large organizations, helping customers manage and transform their technology infrastructure for digital transformation |
20,070 | |||
| 3 |
Iron Mountain EMEAironmountain.co.uk
Global leader in storage and information management services with a vast network of facilities worldwide, offering solutions for records, data, and document management |
15,148 | |||
| 4 | 8,687 | ||||
| 5 |
Vodafone Businessvodafone.com
Providing mobile, fixed, unified communications, IoT, cloud, and security services to businesses globally, regionally, and locally. |
8,100 | |||
| 6 |
Colt Technology Servicescolt.net
Global digital infrastructure provider connecting businesses across 40+ countries with extensive networks, customer-focused innovation, and reliable connectivity solutions. |
5,107 | |||
| 7 |
Logicalislogicalis.com
A global technology service provider helping organizations succeed in a digital-first world through cloud, connectivity, collaboration, and security solutions |
4,868 | |||
| 8 |
Infobipinfobip.com
Global leader in omnichannel engagement, providing messaging tools and solutions for customer engagement, authentication, and security with a strong focus on quality engineering |
3,501 | |||
| 9 |
Claranetclaranet.com
A global technology services provider offering managed services, professional services, and training in Cloud, Networks, Cyber Security, and Workplace technologies since 1996 |
3,073 | |||
| 10 |
Telent Technology Services Ltdtelent.com
Leading technology company specializing in designing, building, operating, and maintaining critical digital infrastructure for public sector, transport, emergency services, and network providers |
2,675 | |||
| 11 |
Gammagammagroup.co
Gamma is a leading supplier of Unified Communications services in the UK, Germany, Spain, and Benelux, offering robust solutions for communication and collaboration |
2,588 | |||
| 12 |
NTT Global Data Centersservices.global.ntt
Global Data Centers, now a part of NTT DATA, offers neutral access to cloud providers, internet exchanges, and telecom providers with reliable data centers worldwide |
2,449 | |||
| 13 |
Canonicalcanonical.com
Publishing Ubuntu, popular enterprise Linux, open source delivery, cloud to edge, secure, cost-effective, global community, developer platform, remote-first company. |
2,001 | |||
| 14 | 1,667 | ||||
| 15 | 1,660 | ||||
| 16 |
CDS, an HPE companyhpecds.com
Delivers customer experience and services across HPE Edge-to-Cloud platforms, offering early career technical roles and professional development opportunities to aspiring talent. |
1,604 | |||
| 17 | 1,442 | ||||
| 18 |
Connectweconnect.tech
Communication experts providing solutions in Contact Centre, Unified Communications, and Network Services, delivering digital transformation through bespoke strategies for businesses globally |
1,387 | |||
| 19 |
Daisy Grouplinkedin.com
A leading provider of communications, IT, and cloud services in the UK and internationally, offering solutions for businesses of all sizes |
1,368 | |||
| 20 |
Advania UKadvania.co.uk
Specializes in Microsoft technologies like AI, Azure, and Dynamics 365 to deliver transformational IT services and sustainable value for customers. |
1,351 | |||
| 21 |
Jiscjisc.ac.uk
National research infrastructure providing high-speed connectivity, cyber security, and technology solutions to UK universities and schools through shared services and digital data tools. |
1,333 | |||
| 22 |
Focus Groupfocusgroup.co.uk
Provides essential business technology, including telecoms, IT, connectivity, mobile, cyber security, and energy solutions for various organizations, ensuring optimized and secure operations. |
1,315 | |||
| 23 |
MASSmass.co.uk
A dynamic technology company within the Cohort plc group, specializing in electronic warfare support, cyber security, IT managed services, and data management |
1,294 | |||
| 24 |
Wavenetwavenet.co.uk
A UK-based company providing unified communications, business telephony, and Cyber Security solutions to help businesses overcome real challenges and achieve brilliance |
1,284 | |||
| 25 |
First Technology UKfirst-technology.co.uk
A group of companies providing IT products and services to help organizations navigate technology challenges and achieve their business outcomes |
1,224 | |||
| 26 |
NSC Globalnscglobal.com
This company simplifies global business with expert teams delivering IT services to clients in over 180 countries, flexibly adapting to their needs |
1,070 | |||
| 27 | 1,015 | ||||
| 28 | 975 | ||||
| 29 | 971 | ||||
| 30 |
Maintelmaintel.co.uk
Provider of cloud communications and managed services, specializing in digital transformation for public and private sectors Delivering digital workplace, customer experience, and secure connectivity solutions globally |
946 | |||
| 31 |
Node4node4.co.uk
Node4 specializes in providing a wide range of tech solutions and managed services to help organizations achieve their strategic goals through digital transformation |
933 | |||
| 32 |
Dimension Data UKIservices.global.ntt
This company helps organizations achieve their goals through digital infrastructure, hybrid cloud, workspaces, and cybersecurity, empowering businesses to excel and grow with ICT solutions |
895 | |||
| 33 |
Bell Integrationbell-integration.com
Provides technology consultation and managed services enabling organizations to transform IT capabilities, enhancing productivity, and cost efficiency. Specializes in IT services and infrastructure. |
885 | |||
| 34 |
Bytes Software Servicesbytes.co.uk
Provider of IT solutions including cloud, security, AI, data management, licensing, training, deployment, and managed services for diverse sectors. |
868 | |||
| 35 |
EXA Infrastructureexainfra.net
A leading digital infrastructure platform in Europe and North America, owning a vast fibre network, data centers, and sub-sea routes for optimal connectivity |
846 | |||
| 36 |
Arrow Business Communicationsaro.tech
Provides cloud, collaboration, and sustainability IT solutions to major UK clients including FTSE100 companies, law firms, universities, NHS, and emergency services. |
836 | |||
| 37 |
Cobraamazingsupport.co.uk
We successfully completed a company acquisition in June 2012 resulting in a re-brand to Amazing Support, providing quality business solutions |
831 | |||
| 38 |
DC Thomsondcthomson.co.uk
A leading UK media organization diversifying into publishing, digital technology, radio, TV, events, genealogy, cloud solutions, and a variety of media brands |
815 | |||
| 39 | 782 | ||||
| 40 |
Xyratexseagate.com
A provider of Intelligent Information Infrastructure solutions, helping organizations handle digital data growth and meet next-generation workload demands |
761 | |||
| 41 |
Nasstarnasstar.com
specialise in managed technology services including cloud optimisation, application modernisation, networking, security, and consultative implementation for business success |
755 | |||
| 42 | 752 | ||||
| 43 |
Onecomonecom.co.uk
The UK's top business telecoms provider offering communication services and unified solutions like fixed-line voice, connectivity, and managed cloud to 80,000+ clients |
742 | |||
| 44 | 706 | ||||
| 45 |
Exponential-eexponential-e.com
Provides superfast network and cloud infrastructure delivering tailored enterprise solutions including data centre, cloud, unified communications, security, and IT services. |
695 | |||
| 46 |
Systal Technology Solutionssystaltech.com
Specialist in managing complex network, cloud, and security services globally, enabling enterprise businesses to transform technology and maximize IT value. |
694 | |||
| 47 |
Zenzerozenzero.co.uk
Design tailored IT infrastructure solutions using proven technologies to optimize client operations and maximize value from resources. |
688 | |||
| 48 | 679 | ||||
| 49 |
Littlefish Grouplittlefish.co.uk
Providing 24/7 IT support, cyber security, cloud solutions, managed infrastructure, and consultancy for enterprise organisations across sectors. |
674 | |||
| 50 |
Onneconnecgroup.com
A leading technology partner offering end-to-end connectivity solutions including structured cabling, networking, managed services, and integrated intelligent systems for businesses globally |
665 | |||
Want more companies than this list?This page shows the largest ones only. Connect to Tamtam to see every company that matches, filter by size, industry or growth, and reach their decision-makers. | |||||
| 51 |
Options Technologyoptions-it.com
Provides global financial technology solutions specializing in banking and trading infrastructure, integrating high-performance networking, cloud, security, and AI technologies. |
641 | |||
| 52 |
Acora - IT, Cyber & AIacora.com
UK-based company offering IT support, cybersecurity, applications, data management, and cloud solutions to protect and optimize business technology. |
639 | |||
| 53 |
Giacomgiacom.com
The company provides a platform for technology resellers and MSPs to access various services and products to create solutions for UK small businesses |
633 | |||
| 54 |
Phoenix Softwarephoenixs.co.uk
Innovative UK IT solutions provider driving digital transformation with cloud, data, AI, security, and collaboration tools Recognized for diversity and Microsoft partnership |
605 | |||
| 55 | 604 | ||||
| 56 |
Redcentricredcentricplc.com
A managed service provider delivering network, cloud, and collaboration solutions to help public and private sector organizations succeed with agile and assured services |
602 | |||
| 57 |
Nscalenscale.com
Specializing in AI, Nscale provides a GPU cloud platform in Europe for high-performance computing optimized for training and intensive workloads |
585 | |||
| 58 | 578 | ||||
| 59 |
Ultimaultima.com
Providing end-to-end cloud, security, data, and AI solutions with tailored managed services for global private and public sector clients. |
575 | |||
| 60 |
Zen Internetzen.co.uk
Telecommunications and technology service provider offering business broadband, Ethernet, data services, and expert cloud solutions for diverse business needs. |
562 | |||
| 61 | 561 | ||||
| 62 |
TelefΓ³nica Tech (EN)telefonicatech.uk
Specialist provider of integrated technology solutions including cybersecurity, cloud, data, AI, business applications, and digital workplace services. |
557 | |||
| 63 |
Sharp UKsharp.co.uk
Innovative workplace technologies and services that support new ways of working, designed to benefit people's lifestyles and work styles |
548 | |||
| 64 |
Fortray Global Service Limitedfortray.com
Provides services for digital transformation, cybersecurity, cloud, and managed IT. Also develops talent through tech and AI bootcamps for various digital skills. |
547 | |||
| 65 |
TalkTalk Businessbusiness.talktalk.co.uk
Providing UK businesses with internet, data, voice, and network infrastructure solutions alongside managed services and dedicated support. |
538 | |||
| 66 |
Lemongrasslemongrasscloud.com
Provides automated managed services for SAP on Cloud, enabling scalable, agile, and innovative enterprise solutions with near zero downtime migrations. |
535 | |||
| 67 |
Medhurstmedhurst-it.com
Providing cost-effective and flexible IT solutions for businesses and the public sector, relieving clients of IT management burdens to focus on core business |
525 | |||
| 68 |
Colt Data Centre Servicescoltdatacentres.net
Specializing in data centre services, the company designs, builds, manages, and innovates infrastructure solutions to support customers' growth globally |
483 | |||
| 69 |
Intercityintercity.technology
Intercity helps businesses improve their IT capabilities and solve technology issues, focusing on cloud, security, communications, and managed IT services |
472 | |||
| 70 |
Hitachi Solutions UKhitachi-solutions.co.uk
Provides business-tailored services and solutions for transformation journeys, including finance, low code, AI, and data-based transformation, offering advisory and application support. |
462 | |||
| 71 |
EPI-USE Labsepiuselabs.com
Global software solutions company specializing in maximizing SAP system performance, simplifying data management, and helping clients navigate business challenges successfully |
454 | |||
| 72 |
Global Switchglobalswitch.com
Ownership and operation of large-scale, carrier-neutral data centers across Europe and Asia-Pacific, providing secure, resilient solutions to diverse customers. |
447 | |||
| 73 |
Trustmarquetrustmarque.com
Delivers technology value through IT solutions, helping organizations acquire and adopt the right technology to create innovation across various IT domains. |
431 | |||
| 74 |
Iomartiomart.com
Cloud computing and IT managed services provider offering secure hybrid cloud, network connectivity, data management, and digital workplace capabilities to enable businesses to operate seamlessly |
426 | |||
| 75 |
Air IT Groupairit.co.uk
Provides managed IT services including cybersecurity, business intelligence, automation, cloud solutions, and IT support to optimize and scale SME operations. |
419 | |||
| 76 |
EPCCepcc.ed.ac.uk
Provider of supercomputing and data services to industry and academia, offering advanced computing facilities, education & training programs, and cutting-edge research in HPC and data science |
414 | |||
| 77 | 412 | ||||
| 78 |
Babblebabble.cloud
The company specializes in simplifying the use, deployment, and management of next-generation technology for ambitious businesses |
411 | |||
| 79 |
Easynet Groupeasynet.com
A provider of managed services for national and global businesses, offering network, hosting, and unified communications solutions, along with security and application performance management |
408 | |||
| 80 |
Elevateelevate.uk
Providing affordable, hyperfast internet access to empower individuals, drive economic growth, and foster technological innovation worldwide. |
402 | |||
| 81 |
ArpaWarearpaware.com
This company specializes in providing cost-effective, high-capacity networking solutions for modern data centers using Open networking and OpenStack technology to reduce costs and complexities |
401 | |||
| 82 |
Transparitytransparity.com
Leading UK Microsoft partner offering professional services, managed services, and licensing to support digital transformation with expertise in various Microsoft technology areas |
397 | |||
| 83 |
PURVIEWpurviewservices.com
Providing IT engineering and talent solutions to mid-market and Fortune 500 companies globally, with expertise in data, AI, cloud, and cybersecurity services. |
395 | |||
| 84 |
MBAmba-it.com
IT solutions and services provider in London, specializing in complex applications, enterprise capabilities, and exceptional service for businesses in finance, legal, and insurance sectors |
388 | |||
| 85 |
prosource.itprosource.it
Managed IT services provider specializing in infrastructure, operational, and project requirements for corporate enterprises globally, with expertise in various industries and locations |
382 | |||
| 86 |
Interouteexainfra.net
A leading digital infrastructure platform connecting Europe and North America with extensive fiber network and data centers, offering low-latency sub-sea routes |
367 | |||
| 87 |
NTT DATA Business Solutions UK&Inttdata-solutions.com
This company specializes in transforming SAP solutions to drive innovation and help businesses become more efficient, effective, and successful globally |
364 | |||
| 88 |
MainOnemainone.net
Leading connectivity and managed services provider, delivering innovative services for digital transformation, including top-tier data center services, network solutions and cloud services in West Africa. |
363 | |||
| 89 |
Daisy Groupβ’daisygroup.co.uk
The company is a leading UK provider of voice, connectivity, mobile, phone systems, and cloud services for businesses across various sectors |
354 | |||
| 90 |
Telehousetelehouse.net
Provider of global data centre colocation services with extensive connectivity, secure facilities, and sustainable operations across major commercial hubs. |
343 | |||
| 91 |
Kochokocho.co.uk
Empowering ambitious companies with Microsoft cloud solutions, identity, mobility, connectivity, and cyber security services for secure growth and business success |
332 | |||
| 92 |
Aspire Technology Solutionsaspirets.com
It is a leading UK provider of managed IT, cyber security, and workplace solutions, serving over 2,000 customers effectively. |
321 | |||
| 93 |
Converge Technology Solutions UKconvergetp.co.uk
Transforming organizations with technology solutions, IT services, and support while championing sustainability and providing bespoke solutions for a variety of industries |
318 | |||
| 94 |
Six Degrees6dg.co.uk
Providing AI-enabled, people-led technology services in Core, Hybrid Cloud, Cyber Security, and Modern Work aligned with client outcomes. |
313 | |||
| 95 |
ARO Technologyaro.tech
A 25-year enterprise specializing in cloud, cyber, IT services, and sustainability Offers advanced cloud technologies, managed services, and secure platforms for high-performing teams |
307 | |||
| 96 |
Armakuniarmakuni.com
The company helps organizations leverage cloud-native technologies and processes to drive growth, increase efficiency, minimize risk, and accelerate delivery for sustainable success |
307 | |||
| 97 |
Total IT Globaltotalitglobal.com
Total IT Global offers innovative hardware and managed IT services for digital workplaces and data centers, specializing in digital transformations for high-growth enterprises |
304 | |||
| 98 |
Pulsantpulsant.com
Provides next-generation cloud, colocation, and connectivity services via 12 edge data centers, enabling regional enterprises and service providers to innovate and grow with edge computing and hybrid cloud environments. |
300 | |||
| 99 |
CCS Media Limited (Advania UK)ccsmedia.com
Leading Northern European IT services provider delivering managed services, hardware, software, and professional support focused on client needs and business outcomes. |
291 | |||
| 100 |
Vorbossvorboss.com
A dedicated fiber network provider in London offering 10Gbps minimum internet service for data-hungry businesses, recognized as a top workplace |
280 | |||
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