| # | 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 |
UK Civil Servicegov.uk
This company implements government policies, delivering essential public services in the UK |
238,504 |
| 3 |
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 |
| 4 | 42,697 | |
| 5 |
British Armymod.uk
The British Army offers opportunities for personal growth, adventure, training, and camaraderie, with a focus on making a difference and building lifelong bonds |
34,120 |
| 6 |
Department for Work and Pensions (DWP)gov.uk
The company is responsible for welfare, pensions, child maintenance, and benefits, aiming to reduce poverty, promote work, and ensure financial security for all |
33,465 |
| 7 |
UK Ministry of Defencegov.uk
The company works to protect the security and interests of the United Kingdom, providing necessary training, equipment, and support for the Armed Forces |
30,901 |
| 8 |
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 |
| 9 |
Ministry of Justice UKgov.uk
Government department responsible for justice system administration, legal affairs, courts, prisons, and public safety in the United Kingdom. |
20,603 |
| 10 |
Metropolitan Policepolice.uk
This organization polices London, handling law enforcement investigations, and also holds national responsibility for specialist units and counter-terrorism policing across the UK. |
19,966 |
| 11 |
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 |
| 12 |
Post Office Ltdpostoffice.co.uk
operates largest UK retail network with 11,500 branches and a major digital presence, focusing on customer service and innovation |
17,058 |
| 13 |
University of Leedsleeds.ac.uk
A top research university in the UK with a focus on creating knowledge, educating students, and making a positive impact through research and innovation |
14,683 |
| 14 |
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 |
| 15 |
University of Glasgowgla.ac.uk
The company focuses on conducting cutting-edge research, providing a student-centered learning environment, and contributing to Scottish culture, the environment, and the economy |
11,990 |
| 16 |
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 |
| 17 |
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 |
| 18 | 9,410 | |
| 19 |
Birmingham City Councilbirmingham.gov.uk
Local government providing services focused on economic growth, safety, health, inclusivity, and environmental sustainability for over one million residents. |
8,580 |
| 20 |
Lancashire County Councillancashire.gov.uk
Local government focused on fairness, community support, narrowing social gaps, and improving quality of life for all residents in Lancashire. |
8,559 |
| 21 |
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 |
| 22 |
Kent County Councilkent.gov.uk
Local government managing public services, infrastructure, and community engagement across Kent, including coordination with district and parish councils. |
7,375 |
| 23 |
Queen's University Belfastqub.ac.uk
A renowned university with over 150 years of academic excellence, offering a wide range of degree programs and a strong research focus |
7,278 |
| 24 |
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 |
| 25 |
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 |
| 26 |
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 |
| 27 |
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 |
| 28 |
Glasgow City Councilglasgow.gov.uk
Providing essential front-line and support services to residents, managing local governance and community needs in Glasgow city. |
6,709 |
| 29 |
House of Commonsparliament.uk
This company supports and educates on the functions of elected MPs in representing the public, legislating, and scrutinizing the Government |
6,657 |
| 30 |
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 |
| 31 |
BBC Studiosbbcstudios.com
BBC Studios is a leading content studio and channels & streaming business known for top-quality, award-winning shows and global distribution of British content |
6,277 |
| 32 |
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 |
| 33 |
National Highwaysnationalhighways.co.uk
Government company managing, maintaining, and modernising motorways and main A roads to ensure smooth traffic flow nationwide. |
5,889 |
| 34 |
NHS Professionalsnhsprofessionals.nhs.uk
Provision of flexible, cost-effective healthcare staff including nurses, doctors, and administrative professionals to support NHS trusts efficiently. |
5,807 |
| 35 |
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 |
| 36 |
Financial Conduct Authorityfca.org.uk
Regulation and supervision of financial firms to ensure fair conduct, protect consumers, and maintain market integrity and stability. |
5,760 |
| 37 |
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 |
| 38 |
Manchester City Councilmanchester.gov.uk
A dynamic city council in Manchester, UK, striving to become a world-class city by 2025 through community involvement and diverse services |
5,556 |
| 39 |
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 |
| 40 |
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 |
| 41 |
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 |
| 42 |
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 |
| 43 |
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 |
| 44 |
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 |
| 45 | 4,789 | |
| 46 |
Suffolk County Councilsuffolk.gov.uk
Local government employer offering diverse careers focused on community impact, environmental responsibility, innovation, collaboration, and personal development. |
4,613 |
| 47 |
NHS Grampiannhsgrampian.org
Providing comprehensive healthcare services and public health management for half a million people across urban and rural Grampian communities. |
4,588 |
| 48 |
University Hospital Southampton NHS FTcareers.uhs.nhs.uk
Innovative healthcare provider specializing in a wide range of services, pioneering medical research, and prioritizing patient-centered care with a commitment to staff development |
4,517 |
| 49 |
Civil Aviation Authoritycaa.co.uk
Regulation and oversight of aviation safety, consumer protection through ATOL, development of aviation technology and environmental standards. |
4,334 |
| 50 |
Sellafield Ltdcareers.sellafieldsite.co.uk
A global leader in nuclear engineering, setting international standards in high-hazard reduction and pioneering nuclear power generation for electricity |
4,333 |
| 51 |
Sheffield Teaching Hospitals NHS Foundation Truststh.nhs.uk
A leading NHS foundation trust in Sheffield providing comprehensive hospital and community services, specializing in cancer, spinal injuries, renal, and cardiothoracic care |
4,301 |
| 52 |
University Hospitals of Leicester NHS Trustuhleicester.nhs.uk
A healthcare organization in Leicester focused on providing top-quality care to the community, earning trust and recognition as #TeamUHL |
4,291 |
| 53 |
Thames Valley District School Boardtvdsb.ca
A public school board serving a diverse region in Ontario, focused on progressive growth, student achievement, equity, and community partnerships |
4,232 |
| 54 |
University of Dundeedundee.ac.uk
A university focused on transforming lives through education, research, and innovation to drive global impact and improve societal wellbeing |
4,046 |
| 55 |
North London NHS Foundation Trustnorthlondonmentalhealth.nhs.uk
Providing community-based and inpatient mental health care services across North London boroughs, supporting local and wider populations. |
3,983 |
| 56 |
Nottingham University Hospitals NHS Trustnuh.nhs.uk
Large healthcare provider, offering specialist medical services in stroke, renal, neurosciences, cancer, and trauma. Also a leader in medical research and education. |
3,965 |
| 57 |
South London and Maudsley NHS Foundation Trustslam.nhs.uk
Provider of extensive mental health and substance misuse services, combining clinical care, research, and training in South London. |
3,947 |
| 58 |
Great Ormond Street Hospital for Children NHS Foundation Trustgosh.nhs.uk
National centre providing specialist healthcare for children with complex, rare, and congenital conditions, focusing on research and teaching partnerships. |
3,938 |
| 59 |
The University of Huddersfieldhud.ac.uk
Innovative university in Huddersfield offering high-quality education, research, and practical experience, with a focus on student success and achievement |
3,907 |
| 60 |
Central and North West London NHS Foundation Trustcnwl.nhs.uk
Integrated healthcare provider in Central and North West London, also serving Milton Keynes, Surrey, and beyond Offers diverse services for various health needs |
3,898 |
| 61 |
North Lanarkshire Councilnorthlanarkshire.gov.uk
Local authority in west-central Scotland providing services such as education, social work, housing, and environmental services to various communities in the region |
3,893 |
| 62 |
Warwickshire County Councilwarwickshire.gov.uk
Provides education, social care, cultural activities, fire services, trading standards, highways maintenance, and strategic planning for community welfare. |
3,798 |
| 63 |
Education Authority (Northern Ireland)eani.org.uk
The Education Authority delivers essential education services to schools and youth centers in Northern Ireland, focusing on ensuring every child can reach their full potential |
3,785 |
| 64 |
Dorchester Collectiondorchestercollection.com
Collection of luxury hotels and residences known for unique character, cultural significance, and providing sophisticated, legendary guest experiences worldwide. |
3,763 |
| 65 |
East London NHS Foundation Trustelft.nhs.uk
Provider of mental health care, innovation, and improvement services in East London and beyond Earning awards and striving for excellence |
3,749 |
| 66 |
Frimley Health NHS Foundation Trustcareers.fhft.nhs.uk
A leading healthcare provider serving a population of 900,000, offering exceptional hospital services, specialized treatments, outpatient clinics, and strong community connections |
3,626 |
| 67 |
Greater Manchester Policegmp.police.uk
A large police force responsible for ensuring the safety of almost 3 million diverse residents in Greater Manchester, UK |
3,623 |
| 68 |
University Hospitals Coventry and Warwickshire (UHCW) NHS Trustuhcw.nhs.uk
This company is one of the largest acute teaching hospitals in the UK, offering major advances in patient care, clinical teaching, and innovation |
3,622 |
| 69 |
Lincolnshire County Councillincolnshire.gov.uk
Providing modern, responsive public services to Lincolnshire residents, valuing workforce diversity, and promoting inclusive, flexible employment practices. |
3,583 |
| 70 |
Leicestershire County Councilleicestershire.gov.uk
Providing social care, waste disposal, road maintenance, and supporting community development for over 650,000 residents daily. |
3,559 |
| 71 |
Maidstone and Tunbridge Wells NHS Trustmtw.nhs.uk
A large acute hospital trust in the south east of England, providing general and specialist care to over 560,000 people |
3,543 |
| 72 |
Chelsea and Westminster Hospital NHS Foundation Trustchelwest.nhs.uk
A NHS Foundation Trust running two hospitals and community services, providing outstanding healthcare to a million people with innovative outreach programs |
3,504 |
| 73 |
UK Health Security Agencywww.gov.uk
The company is an executive agency responsible for planning, preventing, and responding to external health threats at national and global levels |
3,430 |
| 74 | 3,371 | |
| 75 |
Student Loans Companygov.uk
Provide financial support through loans and grants for tuition fees, living costs, and study expenses to UK university and college students. |
3,312 |
| 76 |
Bradford Councilbradford.gov.uk
Local government providing social care, education, housing, highways, planning, environmental protection, libraries, waste collection, and recreational facilities for residents. |
3,256 |
| 77 |
NHS National Services Scotlandnss.nhs.scot
This company supports Scotland's health by providing shared services and expertise to help NHS Boards work more efficiently and save money |
3,190 |
| 78 |
London Borough of Newhamnewham.gov.uk
Local government focused on urban regeneration, supporting diverse communities, enhancing connectivity, and creating opportunities for residents and businesses. |
3,187 |
| 79 |
London Borough of Lambethbeacons.ai
Providing planning, social work, housing, and education services to a diverse community of over 300,000 residents and businesses. |
3,148 |
| 80 |
Newcastle City Councilnew.newcastle.gov.uk
Local government providing public services and governance for Newcastle upon Tyne, representing 78 councillors across 26 wards serving residents. |
3,140 |
| 81 |
NELFT NHS Foundation Trustnelft.nhs.uk
Extensive integrated community and mental health services across London boroughs, Essex, Kent, and Medway for all age groups. |
3,135 |
| 82 |
University Hospitals Bristol and Weston NHS Foundation Trustuhbw.nhs.uk
A large NHS Trust in South West England providing a wide range of clinical services, committed to delivering excellent care and innovative research |
3,121 |
| 83 |
Scottish Waterscottishwater.co.uk
Providing high-quality drinking water and safely returning wastewater to the environment across communities throughout Scotland every day. |
3,115 |
| 84 |
Cardiff and Vale University Health Boardcavuhb.nhs.wales
Healthcare provider offering a wide range of services to a local population of 500,000, with over 100 specialist services for the region and beyond |
3,110 |
| 85 |
Oxford Health NHS Foundation Trustoxfordhealth.nhs.uk
Provider of physical, mental health, and social care across multiple regions, with a focus on community-based services, research, and collaborations with universities |
3,054 |
| 86 |
Norfolk and Norwich University Hospitals NHS Foundation Trustnnuh.nhs.uk
Large teaching hospital providing specialist medical services, training health professionals, conducting research, and serving over 800,000 patients regionally and beyond. |
2,987 |
| 87 |
Islington Councilislington.gov.uk
Local government focused on affordable housing, job investment, environmental health, youth development, and fostering safe, inclusive community connections. |
2,986 |
| 88 |
Richmond and Wandsworth Councilsjobs.richmondandwandsworth.gov.uk
Deliver high-quality public services across two London boroughs, supporting communities through innovation, collaboration, and adapting to change. |
2,965 |
| 89 |
The Royal Marsden NHS Foundation Trustroyalmarsden.nhs.uk
Cancer diagnosis, treatment, research, and education, operating two hospitals in London and Surrey, and partnering with The Institute of Cancer Research. |
2,930 |
| 90 |
Mersey and West Lancashire Teaching Hospitals NHS Trustmerseywestlancs.nhs.uk
Healthcare services provider with hospitals in Whiston, Southport, St Helens, Ormskirk, and Newton, in addition to community and primary care services |
2,925 |
| 91 |
London Fire Brigadelondon-fire.gov.uk
Full-time firefighters and support staff protect people and property from fire across Greater London, operating 24/7 emergency response system. |
2,894 |
| 92 |
East Kent Hospitals University NHS Foundation Trustekhuft.nhs.uk
Leading hospital trust in England with five hospitals and community clinics, providing specialist services for a population of 759,000 Focused on high-quality care, research, and education |
2,887 |
| 93 |
Medical Research Councilukri.org
A publicly funded organization promoting world-class medical research to enhance human health across various institutions in the UK and Africa |
2,881 |
| 94 |
Royal Devon University Healthcare NHS Foundation Trustroyaldevon.nhs.uk
A healthcare organization offering top-quality care to a population of 615,000, with state-of-the-art equipment, support for professional development, and a nurturing, family-like work environment |
2,865 |
| 95 |
Somerset NHS Foundation Trustsomersetft.nhs.uk
Provider of community, mental health, and acute hospital services in Somerset Awarded Mental Health Trust of the Year in 2021 |
2,864 |
| 96 |
Care Quality Commissioncqc.org.uk
Independent regulator ensuring safe, effective, compassionate, and high-quality health and adult social care services in England. |
2,847 |
| 97 |
Edinburgh Napier Universitynapier.ac.uk
A leading Scottish higher education institution offering industry-informed courses for over 19,000 students worldwide to prepare graduates for the global job market |
2,815 |
| 98 |
Channel 4channel4.com
Free-to-air UK broadcaster offering multiple TV channels and streaming, commissioning independent content, focusing on young audiences and British film investment. |
2,807 |
| 99 |
Ealing Council (London Borough of Ealing)ealing.gov.uk
A diverse London borough focused on generating jobs, improving lives, and addressing climate crisis and inequality through resident engagement and innovative services |
2,807 |
| 100 |
London Ambulance Service NHS Trustlondonambulance.nhs.uk
This company is the busiest emergency ambulance service in the UK, providing free emergency and urgent healthcare in London |
2,724 |
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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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