| # | Company | Employees |
|---|---|---|
| 1 |
NHSwww.nhs.uk
It provides comprehensive healthcare services to UK residents, employing over 1.5 million staff and ensuring free access at the point of use. |
252,871 |
| 2 | 208,511 | |
| 3 | 197,879 | |
| 4 |
Vodafonevodafone.com
Using technology to connect people globally, drive social change, and improve lives while emphasizing the importance of humanity and collaboration |
142,740 |
| 5 | 85,000 | |
| 6 |
Barclayshome.barclays
A British universal bank with global presence, offering consumer banking, payments, corporate and investment banking services, supported by technology and operational solutions |
82,417 |
| 7 |
Standard Charteredsc.com
An international banking group with a presence in 53 markets, driving commerce and prosperity through diversity and values Listed on London and Hong Kong Stock Exchanges |
79,401 |
| 8 | 73,712 | |
| 9 |
NHS Englandengland.nhs.uk
This organization collaborates with NHS Improvement to enhance care delivery, transparency, and services for patients in England while prioritizing efficiency and accountability |
59,120 |
| 10 |
Lloyds Banking Grouplloydsbankinggroup.com
This company focuses on creating a more sustainable and inclusive future in the financial services industry, while supporting customers' changing needs |
57,702 |
| 11 |
NatWest Groupnatwestgroup.com
Support UK businesses by removing barriers, promoting learning, enhancing financial confidence, and championing climate solutions for sustainable community growth. |
43,833 |
| 12 |
Royal Maillinktr.ee
Connecting businesses, customers, and communities in the UK by providing universal postal service to over 29 million addresses, aiming to be the best delivery company in Europe |
39,215 |
| 13 | 36,000 | |
| 14 | 35,346 | |
| 15 |
Network Railnetworkrail.co.uk
Managing and modernising Britain's railway infrastructure to ensure safe, reliable transport for passengers and freight, supporting economic growth. |
28,033 |
| 16 |
Boots UKboots.jobs
Leading UK pharmacy-led retailer offering health, beauty products & care services through retail stores, digital platforms, and exclusive brands for over 170 years |
27,869 |
| 17 | 25,298 | |
| 18 |
Santander UKsantander.co.uk
Providing personal and commercial financial products and services to millions of customers, fostering diversity and a positive workplace culture. |
21,000 |
| 19 |
Bupa UKbupa.co.uk
International healthcare company dedicated to helping people live longer, healthier, happier lives by providing quality healthcare services to over 38 million customers worldwide |
20,537 |
| 20 |
Menzies Aviationmenziesaviation.com
Providing ground handling, air cargo, and fueling services worldwide, ensuring safety, precision, and continuous support in aviation operations. |
18,695 |
| 21 |
Transport for Londontfl.gov.uk
London-based transportation company leading in providing diverse travel options, focusing on customer feedback, technology innovation, and large-scale investments for city-wide mobility improvements |
18,658 |
| 22 |
Revolutrevolut.com
A fintech company on a mission to provide customers with more visibility, control, and freedom over their money through innovative products |
18,462 |
| 23 |
RBSnatwestgroup.com
Announcement of rebranding from RBS to NatWest Group, encouraging followers to transition to the new company page for updates. |
18,457 |
| 24 |
Centricacentrica.com
A leading energy services provider with a focus on sustainability, offering zero carbon electricity to millions of customers through various brands |
18,164 |
| 25 |
National Gridnationalgrid.com
Operate and develop electricity transmission and distribution networks, natural gas systems, and invest in clean energy infrastructure and technology ventures. |
17,432 |
| 26 |
Openreachopenreach.com
This company is the UK's digital network business, connecting homes, businesses, and more to the world with a focus on high-quality service |
16,885 |
| 27 |
Babcock International Groupbabcockinternational.com
An international defence company providing product and service solutions to enhance customers' capabilities and assets, offering opportunities for professionals to grow |
16,474 |
| 28 |
Nationwide Building Societynationwide.co.uk
Providing reliable and customer-focused banking services, offering financial products and support to meet everyday banking needs effectively. |
14,486 |
| 29 |
easyJeteasyjet.com
Mission-driven to make low-cost travel accessible with Europe's best airline network, value fares, and personalized service, fostering a supportive, opportunity-driven culture |
13,948 |
| 30 |
Liverpool University Hospitals NHS Foundation Trustuhliverpool.nhs.uk
Provides general hospital, specialist, cancer, dental, and community healthcare services, including major trauma care for Cheshire and Merseyside. |
13,000 |
| 31 | 12,865 | |
| 32 |
Bank of Communications Co., Ltd. London Branchbankcomm.com.hk
Provides commercial banking, securities, trust services, financial leasing, fund management, and insurance through a vast network of domestic branches and international overseas institutions. |
12,670 |
| 33 | 12,146 | |
| 34 | 11,769 | |
| 35 |
Guy's and St Thomas'β NHS Foundation Trustguysandstthomas.nhs.uk
Provides high-quality healthcare services, clinical excellence, research, and community care through multiple hospitals and partnerships in London. |
11,655 |
| 36 | 11,000 | |
| 37 | 10,917 | |
| 38 |
British Gasbritishgas.co.uk
Providing affordable energy services and support to millions of UK homes and businesses, focusing on saving energy and money. |
10,311 |
| 39 |
Barts Health NHS Trustbartshealth.nhs.uk
Managing five London hospitals including specialist heart and cancer services while providing safe quality medical care for diverse and deprived local communities. |
10,093 |
| 40 |
Barclays UKsearch.jobs.barclays
A company focused on helping individuals progress in their lives through financial services, digital innovation, career guidance, and customer-centric approach |
9,925 |
| 41 |
Investecinvestec.com
Provides global banking and asset management services, creating and managing wealth through specialized financial solutions and insights for diverse international clients. |
9,732 |
| 42 |
Nuffield Healthnuffieldhealth.com
Leading UK not-for-profit healthcare organization, investing all income back into hospitals, fitness clubs, and wellbeing services to build a healthier nation. |
9,066 |
| 43 |
RSAintactinsurance.co.uk
A multinational insurer with a 300-year heritage, operating across Europe with significant businesses in the UK, Ireland, and Luxembourg Employing over 4,500 people |
8,918 |
| 44 |
Jet2.com and Jet2holidaysjet2careers.com
A leisure flight and package holiday operator with over 40 years of success, offering great value and service across Europe |
8,917 |
| 45 |
EDF (UK)edfenergy.com
Leading sustainable energy transition, building nuclear power, investing in renewables like wind and solar, and electrifying homes and businesses with low-carbon technology. |
8,774 |
| 46 |
Allianz UKallianz.co.uk
Global financial services provider offering commercial and personal insurance products through brokers, focusing on employee growth, diversity, and sustainability for a better future |
8,735 |
| 47 |
Virgin Media O2virginmediao2.co.uk
Provides fastest broadband and largest mobile network in the UK, focusing on customer-first connectivity services and network upgrades. |
8,272 |
| 48 |
Vodafone Businessvodafone.com
Providing mobile, fixed, unified communications, IoT, cloud, and security services to businesses globally, regionally, and locally. |
8,100 |
| 49 |
Legal & Generallegalandgeneral.com
Provides financial services through asset management, pension risk transfers, and retail savings while investing capital responsibly to deliver long-term shareholder returns. |
7,832 |
| 50 |
Virgin Atlanticvirginatlantic.com
Operate transatlantic flights connecting major global cities, focus on customer experience, sustainability, inclusivity, and innovative travel solutions. |
7,756 |
| 51 |
Virgin Mediajobs.virginmediao2.co.uk
Providing ultrafast broadband and fibre optic network services to connect millions of homes and businesses with reliable internet access. |
7,691 |
| 52 |
TP ICAPtpicap.com
Specialist in connecting clients to liquidity and data solutions across financial and commodities markets with advanced technology and global presence. |
7,548 |
| 53 |
NHS Greater Glasgow and Clydenhsggc.scot
Provider of NHS health care services serving 12 million people in Glasgow and half of Scotland's population, with 25 hospitals and a Β£842m investment program |
7,466 |
| 54 |
Imperial College Healthcare NHS Trustimperial.nhs.uk
Delivers acute and specialist medical care, conducts biomedical research, and provides clinical education for healthcare professionals across five London hospital sites. |
7,248 |
| 55 |
Manchester University NHS Foundation Trustmft.nhs.uk
A large UK acute Trust with nine hospitals providing comprehensive general to highly specialized services to 750,000 people in Manchester and Trafford |
7,150 |
| 56 |
NatWestnatwest.com
Provides comprehensive banking services to personal, small business, and SME customers, supports the UK economy through lending to businesses, and fosters entrepreneurship. |
7,041 |
| 57 |
NHS Lothiannhslothian.scot
Provider of primary, community-based, and acute hospital services in Edinburgh and surrounding areas, offering comprehensive healthcare to local populations |
7,007 |
| 58 |
Thames Waterthameswater.co.uk
Providing clean water and wastewater services to millions, maintaining infrastructure, ensuring quality, investing in sustainability and community education. |
7,000 |
| 59 |
Severn Trentseverntrent.com
Provision of clean water and safe wastewater removal for homes, schools, businesses, and hospitals, focusing on community care and quality service. |
7,000 |
| 60 |
Perencoperenco.com
An independent hydrocarbon producer, involved in the entire lifecycle of projects, from exploration to decommissioning, operating globally with a strong team. |
6,910 |
| 61 |
Mobico Group PLCmobicogroup.com
A leading international transport provider operating in 11 countries, promoting safe, affordable, and reliable public transport for the benefit of the planet |
6,835 |
| 62 |
Leeds Teaching Hospitals NHS Trustleedsth.nhs.uk
One of Europe's largest acute hospital trusts in Leeds, providing healthcare, specialist services, training, research, and pioneering treatments with 20,000 employees |
6,812 |
| 63 |
Spire Healthcare Group plcspirehealthcare.com
Leading provider of private healthcare services operating 38 hospitals and over 50 clinics, consulting rooms, and medical centres in the UK. |
6,621 |
| 64 |
Coventry Building Societycoventrycareers.co.uk
Financial institution offering diverse career opportunities, focusing on member-first service, innovation, and promoting equality, diversity, and inclusion. |
6,612 |
| 65 |
King's College Hospital NHS Foundation Trustkch.nhs.uk
A large and busy Trust providing care to 1 million people, with a commitment to excellence and a global reach strategy in place |
6,425 |
| 66 |
Three UKthreev1-1481200-gb-engb.sr-attrax.com
Provides mobile network services, including 3G, 4G, and 5G, covering 99% of the UK outdoor population and sponsoring Chelsea FC. |
6,239 |
| 67 |
Lloyds Banklloydsbank.com
A UK-based bank focusing on serving the needs of individuals and businesses, prioritizing what truly matters in life Connect with us online |
5,996 |
| 68 |
Heathrowheathrow.com
Europe's largest airport connecting over 80 airlines, passengers, businesses, and cargo to more than 200 global destinations. |
5,968 |
| 69 |
Bank of Englandbankofengland.co.uk
Maintains monetary and financial stability to promote the public good and benefit of the people in the United Kingdom. |
5,947 |
| 70 |
National Highwaysnationalhighways.co.uk
Government company managing, maintaining, and modernising motorways and main A roads to ensure smooth traffic flow nationwide. |
5,889 |
| 71 |
Barchester Healthcarejobs.barchester.com
Operate over 260 care homes and six hospitals across the UK, delivering high-quality, person-centred care to thousands daily. |
5,859 |
| 72 |
Care UKcareuk.com
Award-winning provider of care services, specializing in supporting over 7,000 individuals to live active and fulfilling lives in safe, comfortable environments |
5,843 |
| 73 |
Circle Health Groupcirclehealthgroup.co.uk
Operates UK's largest private hospital group, providing over 500 treatments across 60 specialties with personalized patient care and expert consultants. |
5,791 |
| 74 |
Royal Free London NHS Foundation Trustroyalfree.nhs.uk
A leading London NHS Trust providing high-quality healthcare across three hospitals, focusing on clinical excellence, research, and patient-centered care |
5,782 |
| 75 |
University College London Hospitals NHS Foundation Trustuclh.nhs.uk
Provides acute and specialist medical services across six London hospitals, focusing on patient care, education, and biomedical research. |
5,737 |
| 76 |
Stagecoach Group Limitedstagecoachbus.com
Market leader in providing greener, smarter travel through bus, coach, and tram operations Committed to safety, service, integrity, innovation, and partnership |
5,660 |
| 77 |
Aberdeenaberdeenplc.com
Providing wealth and investment services focused on helping clients plan, manage portfolios, and navigate financial futures with insight. |
5,527 |
| 78 |
University Hospitals Birmingham NHS Foundation Trustuhb.nhs.uk
Operates large teaching hospitals, providing comprehensive medical care, specialist treatments, and trauma services for millions regionally and internationally, with a focus on staff development. |
5,525 |
| 79 |
Priorypriorygroup.com
A leading provider of behavioral care in the UK and internationally, offering healthcare, education, and care services for over 30,000 people annually |
5,504 |
| 80 |
Octopus Energyoctopus.energy
providing affordable, transparent renewable energy solutions with innovative technology and exceptional customer service across multiple countries and sectors |
5,415 |
| 81 |
Moniepoint Groupmoniepoint.com
A leading fintech company offering digital payment solutions, credit access, and business management tools to help businesses worldwide grow and succeed |
5,413 |
| 82 |
Oxford University Hospitals NHS Foundation Trustouh.nhs.uk
A world-renowned NHS teaching trust with four hospitals in Oxford, providing clinical services, specialist care, medical education, training, and research |
5,379 |
| 83 |
O2 (TelefΓ³nica UK)o2.co.uk
Leading UK mobile network operator providing 2G to 5G services, retail stores, WiFi, and partnerships with Tesco Mobile and entertainment venues. |
5,371 |
| 84 |
United Utilitiesunitedutilities.com
Provides water and wastewater services to seven million people in the North West of England through treatment, delivery, and environmental protection measures |
5,299 |
| 85 |
ScottishPowerscottishpower.com
Leading renewable energy generation, managing electricity grids, and supporting homes and businesses in transitioning to a low carbon future. |
5,295 |
| 86 |
Cambridge University Hospitals NHS Foundation Trustcuh.nhs.uk
A leading healthcare provider delivering general, specialist, women's, and maternity care, known for biomedical research, academic health science, and innovative healthcare solutions |
5,288 |
| 87 |
HM Courts & Tribunals Service (HMCTS)gov.uk
This organization oversees the administration of courts and tribunals in England, Wales, Scotland, and Northern Ireland, ensuring fair and efficient access to justice |
5,284 |
| 88 | 5,267 | |
| 89 |
GTRgtrailwaycareers.com
A leading UK train operating company, part of Govia, investing in infrastructure & technology to provide more trains, seats, and services for customers |
5,187 |
| 90 |
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 |
| 91 |
Utility Warehouseuw.co.uk
A growing business focusing on simplifying utilities and providing personalized service to help people spend more time on important things |
5,083 |
| 92 |
Vivo Energyvivoenergy.com
A leading energy company in Africa, distributing Shell and Engen branded fuels and lubricants to retail and commercial customers with a focus on safety, innovation, and customer satisfaction |
5,081 |
| 93 |
St George's University Hospitals NHS Foundation Truststgeorges.nhs.uk
Large healthcare provider offering acute, specialist, community hospital care, and extensive community services including education and medical research. |
4,910 |
| 94 |
Belfast Health and Social Care Trustbelfasttrust.hscni.net
Delivering integrated health and social care services to 340,000 people in Belfast and throughout Northern Ireland, with a focus on improving health and reducing inequalities |
4,902 |
| 95 |
MAG (Airports Group)magairports.com
Ownership and operation of three major UK airports, digital travel services, extensive route network, economic contribution, and sustainability focus. |
4,902 |
| 96 |
Cygnetcygnetgroup.com
Providing health and social care services for individuals with mental health needs, brain injuries, eating disorders, autism, and learning disabilities in the UK. |
4,847 |
| 97 |
HC-Onehc-one.co.uk
Provider of professional residential, nursing, and dementia care for older people across England, Scotland, and Wales, focusing on kindness and making a positive impact in communities |
4,840 |
| 98 | 4,807 | |
| 99 | 4,789 | |
| 100 |
Arriva Grouparrivagroup.com
A leading passenger transport operator in Europe, providing a wide range of transportation services across 10 European countries |
4,733 |
Turn this list into pipeline
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How this list is built
Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Oct 24, 2026.
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