These London-based companies are primarily large research institutions and universities, alongside a significant presence of AI and biomedical research firms. Notable organizations include UCL, King's College London, and Imperial College London, which are major multidisciplinary universities. Google DeepMind specializes in advancing artificial intelligence, while The Francis Crick Institute and The Institute of Cancer Research focus on biomedical and cancer research respectively.
The data shows a strong concentration of academic and medical research, with several institutions founded in the early 20th century. However, there is also a cluster of more recent establishments, such as Google DeepMind (2010), The Francis Crick Institute (2011), and ElevenLabs (2022), indicating growth in AI and advanced biomedical fields.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 | 24,678 | ||||
| 2 |
King's College Londonkcl.ac.uk
Top-ranked university offering world-class education and research, fostering innovation and positive societal impact globally and locally. |
20,705 | |||
| 3 |
Imperial College Londonimperial.ac.uk
Leading university specializing in science, medicine, engineering, and business, fostering interdisciplinary collaboration to advance knowledge and improve health. |
18,233 | |||
| 4 |
Google DeepMinddeepmind.google
Advances artificial intelligence with breakthrough research. Solves complex problems like disease diagnosis, energy saving, and protein folding with safe, ethical AI. |
9,665 | |||
| 5 |
The Francis Crick Institutecrick.ac.uk
Multidisciplinary scientists conducting innovative biomedical research to understand human health and disease, fostering discovery and future science leaders. |
1,957 | |||
| 6 |
The Institute of Cancer Researchicr.ac.uk
Leading cancer research organization and postgraduate college focused on cancer discoveries, treatment, and education with a hospital partnership. |
1,608 | |||
| 7 |
ElevenLabselevenlabs.io
It develops AI audio models for speech and sound effects, enabling content creation, localization, and accessibility for various industries. |
1,291 | |||
| 8 |
Institute of Physicsiop.org
The UK & Ireland's professional body and learned society for physics, promoting cooperation in physics worldwide |
910 | |||
| 9 |
National Centre for Social Researchnatcen.ac.uk
The National Centre for Social Research conducts independent, not-for-profit social research to give the public a voice in shaping impactful services |
798 | |||
| 10 |
Cochranecochrane.org
A global network providing high-quality research summaries to empower healthcare decision-making, free from commercial influence for over 30 years |
698 | |||
| 11 |
Institute of Psychiatry, Psychology & Neurosciencekcl.ac.uk
A leading research and education center in Europe for psychiatry, psychology, and neuroscience, focusing on understanding, preventing, and treating mental and neurological conditions |
676 | |||
| 12 |
Veramedveramed.co.uk
A customer-focused Clinical Research Organisation offering high-quality biostatistics and programming services for the pharmaceutical industry, with a focus on innovation and service excellence |
609 | |||
| 13 | 590 | ||||
| 14 |
The Alan Turing Instituteturing.ac.uk
A UK institute focusing on data science and artificial intelligence research, providing advice to policy makers, facilitating collaboration, and attracting global leaders |
549 | |||
| 15 |
Berlin Institute of Technology (Technische Universit盲t Berlin)media7.net
Leading technical university in Berlin, Germany, with a strong focus on research, teaching, and international partnerships, offering a wide range of academic disciplines and programs |
486 | |||
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. | |||||
| 16 |
Legal 500legalease.dev
A leading publisher of legal market information, offering authoritative analysis and commentary through directories, magazines, journals, textbooks, and online resources since 1987 |
428 | |||
| 17 |
IBweareib.co
A behavioural strategy agency, using psychology to uncover reasons for customer and employee behavior, providing deep insights for business growth |
426 | |||
| 18 |
The British Academythebritishacademy.ac.uk
Mobilizes humanities and social sciences to understand global challenges, invests in researchers, engages public with fresh thinking, and influences policy for everyone's benefit. |
399 | |||
| 19 |
Our Future Health UKourfuturehealth.org.uk
A UK health research programme recruiting adult volunteers to develop new ways to prevent, detect, and treat diseases for better future health |
387 | |||
| 20 |
Health Research Authorityhra.nhs.uk
This organization protects and promotes the interests of patients and the public in health research by simplifying regulation processes and increasing participation |
378 | |||
| 21 |
WEP Clinicalwepclinical.com
A market-leading healthcare services company that creates treatment access solutions for patients worldwide through various programs and services |
356 | |||
| 22 |
Barts Cancer Institute (Queen Mary University of London)bci.qmul.ac.uk
Internationally recognized cancer research institute focusing on early detection, innovative therapies, education, and community engagement to improve patient survival and understanding of cancer |
332 | |||
| 23 |
Connected Places Catapultcp.catapult.org.uk
An innovation accelerator specializing in cities, transport, and place leadership, connecting businesses and public sector leaders to drive growth and reduce carbon emissions |
320 | |||
| 24 |
Ovumomdia.tech.informa.com
The company provides insights and analysis in a variety of industries Follow their new page for updates and information |
167 | |||
| 25 |
Institute For Fiscal Studiesifs.org.uk
An independent research institute informing public debate on economics through rigorous analysis, influencing policy-making and academic scholarship on a global scale |
161 | |||
| 26 |
Biochemical Societybiochemistry.org
A society promoting molecular bioscience through scientific meetings, grants, policy work, and journal publications for researchers at all career stages |
158 | |||
| 27 |
International Growth Centretheigc.org
This organization partners with policymakers in developing countries to drive inclusive and sustainable growth through innovative research and a global network |
156 | |||
| 28 |
OXON Epidemiologyoxonepi.com
A European CRO specializing in Real-World Evidence generation through observational studies, data analysis, and modeling for pharmaceutical and medical device companies worldwide |
59 | |||
| 29 |
Chartis Researchchartis-research.com
Provides in-depth research and analysis on risk technology to support improved risk management, governance, compliance, and informed business decisions. |
33 | |||
| 30 |
Huq Industrieshuq.io
Provider of accurate mobility data intelligence enabling government, retail, real estate, and finance sectors to make informed strategic decisions confidently. |
25 | |||
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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 Nov 12, 2026.
More company lists in London
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- SaaS companies in London 1,615
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