| # | Company | Employees |
|---|---|---|
| 1 |
University of Oxfordox.ac.uk
A leading university in various academic disciplines, fostering innovation, entrepreneurship, and social support while upholding respect and banning hate speech |
23,103 |
| 2 |
Oxfamoxfam.org.uk
A global movement fighting poverty through campaigning for change, development work, and emergency response, with a network of shops and online shop |
9,372 |
| 3 |
Oxford University Pressoup.com
An institution part of the University of Oxford with a 500-year history of providing high-quality research and education resources globally |
8,246 |
| 4 |
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 |
| 5 |
Oxford Brookes Universitybrookes.ac.uk
Leading UK university in Oxford offering diverse courses, research, and services to businesses with strong industry links and a focus on innovation and excellence |
4,862 |
| 6 |
Unipartunipart.com
Global supply chain performance partner designing, making and moving components across automotive, rail, healthcare and technology sectors through data-driven logistics and engineering. |
4,853 |
| 7 |
Oxfordshire County Councillinktr.ee
Collaborating with partners to enhance environmental sustainability, social fairness, and health outcomes for over 725,000 Oxfordshire residents. |
3,946 |
| 8 |
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 |
| 9 |
Saรฏd Business School, University of Oxfordsbs.ox.ac.uk
Developing future leaders through research, teaching, and community, preparing them to address global challenges and lead with purpose and impact |
2,310 |
| 10 |
Lucy Group Ltdlucygroup.com
International group providing sustainable infrastructure, smart energy distribution, advanced street lighting controls, and responsible property development for eco-friendly living. |
1,814 |
| 11 |
Oxford Nanopore Technologiesnanoporetech.com
Innovative biotech company developing portable DNA and RNA sequencing technology for real-time data delivery and scalable analysis in over 100 countries worldwide |
1,352 |
| 12 |
Activate Learningactivatelearning.ac.uk
A pioneering education group offering a holistic approach to learning, focusing on employability and skills development to transform lives and empower individuals and communities |
1,291 |
| 13 |
Aurora Energy Researchauroraer.com
Provide power market forecasting, analytics, advisory support, and software solutions to support investment and financing decisions in energy sector. |
1,188 |
| 14 | 993 | |
| 15 |
Oxford City Counciloxford.gov.uk
Focus on sustainable urban development, housing, community engagement, environmental initiatives, and efficient local government services for diverse population. |
985 |
| 16 | 940 | |
| 17 |
Oxford Policy Managementopml.co.uk
An international development consultancy providing analytical and practical policy expertise to support low- and middle-income societies through global network |
811 |
| 18 |
System Csystemc.com
A UK based company specializing in providing health and social care sectors with robust IT solutions, implementation expertise, and innovative consultancy services |
752 |
| 19 |
Oxford Economicsoxfordeconomics.com
Provide economic analysis, forecasts, data, and advisory services to corporations, governments, and financial institutions worldwide for informed decision-making. |
686 |
| 20 |
Oxford Radcliffe Hospitals NHS Trustoxfordradcliffe.nhs.uk
A leading NHS teaching trust offering general and specialist clinical services, medical education, training, and research opportunities |
649 |
| 21 | 544 | |
| 22 |
Young Enterpriseyoung-enterprise.org.uk
A national charity empowering young people with essential work skills, knowledge, and confidence through programs, resources, and training to reduce youth unemployment |
508 |
| 23 |
Oxford PharmaGenesispharmagenesis.com
A leading HealthScience communications consultancy specializing in accelerating adoption of evidence-based innovations for patients in areas of unmet medical need |
507 |
| 24 |
Leading Edge Aviationleadingedgeaviation.com
Leading Edge Aviation offers innovative pilot training programs focused on personal development and wellbeing, aiming to cultivate well-rounded and skilled pilots |
477 |
| 25 |
Windle Trust Internationalwindle.org.uk
The organization works to improve access to quality education for marginalized communities affected by conflict, displacement, neglect, and discrimination |
421 |
| 26 |
Ellison Institute of Technology Oxfordeit.org
Cutting-edge research and development facility focusing on solving humanity's challenges through technology in healthcare, agriculture, energy, and policy |
395 |
| 27 |
Zzoommzzoomm.com
Building Full Fibre broadband networks for homes and businesses, offering high-speed, tailored connections for work, play, and learning Active on social media during business hours |
386 |
| 28 | 372 | |
| 29 |
Oxera Consulting LLPoxera.com
We provide expert economic advice to companies, policymakers, and lawyers on competition, finance, and regulation, leveraging over 40 years of experience and international presence |
371 |
| 30 |
Shaw Gibbsshawgibbs.com
A UK accountancy practice in Central and Southern England providing expert solutions for businesses and individuals, focusing on client value and utilizing cutting-edge technology |
369 |
| 31 |
The Bodleian Libraries, University of Oxfordbodleian.ox.ac.uk
The Bodleian Libraries at the University of Oxford provide access to over 12 million printed items, rare books, manuscripts, and exhibitions |
368 |
| 32 |
University of Oxford, Department of Physicslinktr.ee
Cutting-edge research and teaching in physics, exploring nature from the smallest to largest scales and contributing to societal challenges Visit website for more |
309 |
| 33 |
Bays Internationalbaysinternational.com
A leading beauty retail company with headquarters in the UK, operating in multiple countries with a focus on luxury brands |
285 |
| 34 |
Ashmolean Museum, Oxfordashmolean.org
An art and archaeology museum at the University of Oxford with collections ranging from Egyptian mummies to contemporary art, showcasing human stories |
266 |
| 35 |
Nominetnominet.uk
Operating for 25 years, this company manages and runs over 11 million UK domain names and offers network security solutions to governments |
265 |
| 36 |
Oxford Archaeology Limitedoxfordarchaeology.com
A leading UK archaeology and heritage practice with over 420 specialists, promoting social value of heritage and maintaining high archaeological standards |
255 |
| 37 | 245 | |
| 38 |
Rhodes Trustrhodeshouse.ox.ac.uk
An organization at Oxford University that identifies and nurtures outstanding individuals worldwide who are motivated to create change |
225 |
| 39 |
Horton Internationalhortoninternational.com
Global executive search firm offering consultative advice and effective solutions to attract and retain senior talent across various industries worldwide |
215 |
| 40 | 201 | |
| 41 |
Keble College, Oxfordkeble.ox.ac.uk
One of the largest constituent colleges within the University of Oxford, originally established in 1870 to provide higher education opportunities. |
195 |
| 42 |
Pickerpicker.org
A not-for-profit organization focusing on person-centered care, influencing policy and practice, improving quality by using experiences to empower healthcare improvement |
193 |
| 43 |
The Oxford Groupoxford-group.com
Global provider of management and leadership training, coaching, and consulting services, focused on unlocking employee potential and improving workplace relationships through tailored solutions |
192 |
| 44 |
Genomicsgenomics.com
A pioneering healthcare company using genomics to transform health through preventative medicine, drug discovery, and personalized risk assessments for common diseases |
187 |
| 45 |
River Learning Trustriverlearningtrust.org
Multi-Academy Trust managing schools and providing teacher training, focused on excellence, collaboration, and supportive relationships to benefit pupils and communities |
185 |
| 46 |
turn IT onturniton.co.uk
Providing hands-on ICT support, MIS, GDPR services, software integration, and training to over 5,000 UK schools and authorities. |
185 |
| 47 |
Oxford University Innovationinnovation.ox.ac.uk
A technology transfer organization supporting University of Oxford staff and students in maximizing research impact for social and economic benefit |
183 |
| 48 |
Oxford Brookes Business Schoolbrookes.ac.uk
Leading business school renowned for excellence in teaching, research, and enterprise Plays a key role in advancing university's mission and vision |
182 |
| 49 |
Merton College, Oxfordmerton.ox.ac.uk
Leading academic institution with a rich history, fostering intellectual growth and research excellence, boasting influential alumni and Nobel Prize winners |
180 |
| 50 |
Balliol College, University of Oxfordballiol.ox.ac.uk
A prestigious college in Oxford with a long history of academic excellence, offering a vibrant community for undergraduate and graduate students |
180 |
| 51 |
Solid State Logicsolidstatelogic.com
A leading manufacturer of audio consoles and creative tools for professionals in live sound, music production, and broadcast Known for unrivaled sonic quality |
179 |
| 52 |
CRM Studentscrm-students.com
A leading serviced living operator offering management services for over 25,000 rooms to corporate, university, and institutional investors across Europe |
173 |
| 53 |
Wadham Collegewadham.ox.ac.uk
An educational institution established in 1610, offering undergraduate and graduate programs to a total of 600 students |
172 |
| 54 |
Dragon School Oxforddragonschool.org
An extraordinary co-ed day and boarding school in Oxford, cultivating kindness, courage, respect, and intellectual curiosity in young learners |
172 |
| 55 |
Refeynrefeyn.com
Revolutionary technology measuring individual molecule mass with light, providing insights into biomolecular structure and dynamics in native environments |
167 |
| 56 |
Huws Gray Plant & Tool Hirehirebase.uk
A one-stop shop for plant, tool, and equipment hire needs with professional service, expert advice, competitive pricing, and nationwide delivery services |
166 |
| 57 |
Flyttrflyttr.com
Innovative team developing safe, self-limiting technology to control disease-transmitting pests, protect crops, and promote environmental sustainability through global partnerships |
165 |
| 58 |
Somerville Collegesome.ox.ac.uk
An inclusive and pioneering university college in Somerville, Oxford, empowering students to make a positive impact on the world |
164 |
| 59 |
d'Overbroeck'sdoverbroecks.com
An independent day and boarding school in Oxford offering GCSEs and over 35 A Level options for students aged 11-18 |
164 |
| 60 |
Department of Computer Science, University of Oxfordcs.ox.ac.uk
A leading research and teaching center in computer science at a top-ranked university, conducting interdisciplinary work with real-world impact |
163 |
| 61 |
Magdalen College School, Oxfordmcsoxford.org
A prestigious independent day school in Oxford for boys aged 7-18 and Sixth Form girls, founded in 1480 by William Waynflete |
162 |
| 62 |
Hertford College, University of Oxfordhertford.ox.ac.uk
A historic Oxford college with over 400 undergraduates, 200 postgraduates, a governing body of 38 Fellows, and a large alumni network |
162 |
| 63 |
University of Oxford, NDORMSndorms.ox.ac.uk
A multi-disciplinary department focused on musculoskeletal diseases, conducting translational research to improve quality of life from bench to bedside |
159 |
| 64 |
Oxford Bus Companyoxfordbus.co.uk
A comprehensive transport company in Oxford, offering city services, airport coaches, park & ride, open-top bus tours, and further regional travel options |
159 |
| 65 |
Oxford Internet Institute, University of Oxfordoii.ox.ac.uk
The company is a multidisciplinary research and teaching department focused on the social science of the Internet, offering Master's and doctoral programs |
158 |
| 66 |
Blackwell's Bookshopsblackwells.co.uk
A leading academic bookseller in the UK, offering a wide selection of titles in flagship shops, on university campuses, and to various businesses and organizations |
157 |
| 67 |
The Queen's College, Oxfordqueens.ox.ac.uk
This organization is a constituent college of the University of Oxford, focused on advancing education, research, and religion for the public benefit |
155 |
| 68 |
Lady Margaret Hall, University of Oxfordlmh.ox.ac.uk
Provides undergraduate and postgraduate education within Oxford University through academic fellows and support staff for students residing in the Norham Gardens area. |
155 |
| 69 |
Trinity College Oxfordtrinity.ox.ac.uk
A prestigious college in Oxford with a diverse and welcoming community, dedicated to success, making a positive impact, and inclusivity |
154 |
| 70 |
St Anne's College, University of Oxfordst-annes.ox.ac.uk
A modern and friendly college in Oxford, UK with a diverse academic focus, offering undergraduate and graduate programs with a welcoming atmosphere |
152 |
| 71 |
St Antony's College, University of Oxfordsant.ox.ac.uk
A prestigious graduate college within the University of Oxford specializing in international relations, economics, and politics with a focus on global issues and regional studies |
150 |
| 72 |
Brasenose College, University of Oxfordbnc.ox.ac.uk
An esteemed institution in Oxford, fostering academic excellence since 1509 with a vibrant community, renowned teaching, and global impact |
149 |
| 73 |
Ingentaingenta.com
A world-leading provider of configurable SaaS solutions for digital publishing platforms, content delivery, contract rights management, and royalty payments across various industries |
141 |
| 74 |
Grafton GBcareers.graftongroup.com
Major player in builders and plumbers merchants industry, integrating Grafton Group's GB businesses to trade from over 400 locations with diverse brands |
115 |
| 75 |
CapitOxcapitox.co.uk
Consulting and finance society in Oxford offering company presentations, networking events, and workshops to help students develop skills for future careers |
112 |
| 76 |
PQShieldpqshield.com
Develops quantum-resistant cryptography solutions, empowering organizations and nations against future cyber threats from quantum computers, modernizing vital security systems and global technology supply chains. |
101 |
| 77 |
Global Canopyglobalcanopy.org
Nonprofit providing open-access data, metrics, and insights to companies, governments, and organizations to improve nature and forest decision-making. |
88 |
| 78 |
Brainomixbrainomix.com
This company specializes in creating AI-powered imaging biomarkers for precision medicine, providing software solutions to help physicians make better treatment decisions worldwide |
87 |
| 79 |
Electricbaseelectricbase.co.uk
A leading electrical wholesaler supplying a wide range of products to contractors, installers, facilities managers, and commercial/industrial users with a focus on innovation and exceptional service |
87 |
| 80 |
Moa Technologymoa-technology.com
The company is dedicated to helping farmers combat herbicide resistance by developing new weed control strategies and chemistries using innovative technology |
87 |
| 81 |
Critchleyscritchleys.co.uk
An established firm offering accounting, compliance, consultancy, and advisory services for individuals, businesses, charities, and not-for-profit organizations with global reach |
86 |
| 82 |
JJ Marketingjjmarketing.co.uk
A full-service marketing agency that generates demand for brands through strategic, creative, and accountable approaches Visit our website for more information |
85 |
| 83 |
Ultromicsultromics.com
A leader in AI for echocardiography, enabling early detection and risk stratification of heart failure for better outcomes through automated analysis |
85 |
| 84 |
Dionach by Nomiosdionach.com
An independent information security consultancy specializing in Penetration Testing, PCI DSS and ISO 27001 Auditing, Incident Response, and Research & Development |
85 |
| 85 |
Elysia - Battery Intelligence from Fortescueelysia.co
A world-leading battery intelligence software harnessing battery expertise to provide unprecedented insights and enhancements for electric vehicles and energy storage |
82 |
| 86 |
OMass Therapeuticsomass.com
A private pharmaceutical company using high-resolution mass spectrometry to discover novel medicines by studying intact protein assemblies for drug leads |
77 |
| 87 |
Adaptix Ltdadaptix.com
Transforming planar X-ray imaging with a Flat Panel X-ray Source for portable, low-cost 3D imaging, supported by prestigious organizations |
73 |
| 88 |
The Pitt Rivers Museumprm.ox.ac.uk
The company is a renowned museum housing over 500,000 objects from around the world, encouraging cross-cultural exploration and challenging boundaries |
71 |
| 89 |
Oxford BioTherapeuticsoxfordbiotherapeutics.com
Develops first-in-class immuno-oncology and antibody-drug conjugate therapies, with a lead asset in clinical development. Discovers oncology targets using a proprietary proteomic database. |
71 |
| 90 |
Imagineraimaginera.co.uk
Imaginera specializes in developing advanced underwriting systems for insurance, reinsurance, ILS, and brokers through a combination of technical expertise and industry knowledge |
70 |
| 91 |
Enara Bioenarabio.com
Enara Bio develops cancer immunotherapies targeting Dark Antigens for improved treatment outcomes, using the pioneering EDAPT platform to discover novel targets |
68 |
| 92 |
Wenn Townsendwenntownsend.co.uk
The company specializes in providing financial management solutions to organizations of all sizes, helping them navigate accounting, tax, and regulation complexities effectively |
66 |
| 93 |
CoreFilingcorefiling.com
A global supplier of financial reporting software with expertise in validation technology, serving regulators, filers, and enterprise organizations worldwide |
63 |
| 94 |
Mind Foundrymindfoundry.ai
Develop responsible AI solutions using sensor fusion and machine learning to enhance frontline operations and protect critical infrastructure environments. |
58 |
| 95 |
Scancellscancell.co.uk
Developing 'off-the-shelf' vaccines and tumour-specific monoclonal antibodies. These advanced therapeutic programs show promising efficacy in trials for metastatic melanoma and solid tumours. |
58 |
| 96 |
Caristo Diagnosticscaristo.com
Brings revolutionary cardiovascular diagnostic tools to patients worldwide. Proprietary technology transforms accuracy of routine cardiac CT scans, enhancing power to predict cardiovascular risk. |
54 |
| 97 |
Ivy Farm Technologiesivy.farm
A company producing guilt-free real meat that is better for the planet, people, and animals, aiming to change the way we feed the world |
54 |
| 98 |
VenCap International plcvencap.com
Manages capital for institutions and family offices, investing exclusively in venture capital funds globally since 1987. Focuses on top-performing VC firms. |
51 |
| 99 |
The Bear Innbearoxford.co.uk
Join our mailing list for a free pint of Fuller's finest beer or glass of wine, exclusive offers, event info, and more |
50 |
| 100 |
GRE Assetsbit.ly
Specialist in property and investment management of UK and Spanish real estate, providing comprehensive services from acquisition to management with a focus on delivering secure assets |
48 |
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 9, 2026.
The same list elsewhere in United Kingdom
- The largest companies in the United Kingdom 30,947
- The largest companies in London 11,159
- The largest companies in Manchester 720
- The largest companies in Birmingham 409
- The largest companies in Leeds 394
- The largest companies in Edinburgh 383
- The largest companies in Glasgow 348
- The largest companies in Cambridge 235
- The largest companies in Nottingham 214
- The largest companies in Liverpool 210
- The largest companies in Bristol 199
- The largest companies in Newcastle upon Tyne 185
- The largest companies in Leicester 182
- The largest companies in Milton Keynes 182
- The largest companies in Sheffield 180
- The largest companies in Reading 172
- The largest companies in Cardiff 154
- The largest companies in Coventry 143
- The largest companies in Belfast 137
- The largest companies in Southampton 117
- The largest companies in Brighton 115
- The largest companies in Aberdeen 112