These London-based organizations specialize in fostering new businesses and initiatives across various sectors. They include venture builders like Blenheim Chalcot, which invests in high-growth areas, and venture capital firms such as ZINC, focused on solutions for people and planet health. Others, like Connected Places Catapult, act as innovation accelerators in specific domains, while Ark is an international charity providing education. Model supports tech startups in the UK with services and connections.
A notable pattern among these entities is their diverse approach to support, ranging from financial investment and venture building to specialized acceleration programs and educational initiatives. Many were founded in the 2010s, indicating a relatively recent surge in structured support for startups and innovation within the city.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 |
Blenheim Chalcotblenheimchalcot.com
A venture builder investing in high-growth sectors by providing funds, expertise, and infrastructure to build profitable, scalable companies globally |
2,370 | |||
| 2 |
Arkarkonline.org
International charity providing quality education through a network of schools and innovative ventures to improve life choices for youth. |
2,039 | |||
| 3 |
Modelstartuply.net
Supporting tech startups in the UK with full-lifecycle services, custom programs, and connections in nine focus areas, without taking equity |
1,816 | |||
| 4 |
Royal College of Artrca.ac.uk
Specialist postgraduate university offering art, design, architecture, and humanities programs focused on innovation, research, and global challenge solutions. |
1,452 | |||
| 5 | 420 | ||||
| 6 |
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 | |||
| 7 |
IMAGINEimagine.one
IMAGINE is a collective founded in 2019 to drive systemic change through transformational leadership and innovation in climate action and social equity |
310 | |||
| 8 |
Digital Catapultdigicatapult.org.uk
Accelerate deep technology adoption by partnering with businesses, investors, and academia to create market pathways and support UK innovation growth. |
307 | |||
| 9 |
Virgin StartUpvirginstartup.org
Offers funding up to 25k per co-founder, provides a community platform for connection and learning, and hosts free monthly events to inspire and network with other founders. |
250 | |||
| 10 | 223 | ||||
| 11 |
UDudmusic.org
UD nurtures and supports Black and culturally diverse artists, providing industry-led events, artist development, and employment support programs to foster excellence and opportunities |
184 | |||
| 12 |
NATO DIANAdiana.nato.int
Locates, accelerates dual-use innovation, provides technology developers with resources, networks, expertise to address critical defense and security challenges, creates a peaceful, resilient future. |
147 | |||
| 13 |
Rainmakingrainmaking.io
An innovation and venture development firm that partners with corporations and entrepreneurs to create, accelerate, and scale new businesses globally |
123 | |||
| 14 |
KERBkerbfood.com
Incubating and accelerating innovative street food businesses in London, bringing amazing food, talented people, and professional practices to transform city spaces and venues |
102 | |||
| 15 |
Outlier Venturesoutlierventures.io
A leading Open Metaverse accelerator program funding and supporting over 100 Web3 startups annually, focused on DeFi, NFTs, and blockchain infrastructure |
101 | |||
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 |
Founders Factoryfoundersfactory.com
Founders Factory builds and funds startups with support, access to industry leaders, and operational expertise for high-growth companies across various sectors |
94 | |||
| 17 |
Infosec Venturesinfosecventures.com
Incubates and scales cyber security innovators, solving inefficiencies, addressing big problems, and delivering high return on investment for customers. |
94 | |||
| 18 |
Tomorrow Londontomorrowltd.com
Fashion incubator providing sales, financial, and operational services for international brands through global showrooms, digital marketplaces, and distribution platforms in key fashion markets. |
92 | |||
| 19 |
The Lightning Groupfounderandlightning.com
Helps founders, startups, investors, and corporates build and scale ventures with product, talent, capital, and AI capability at the core. |
80 | |||
| 20 |
Imperial College Health Partnersimperialcollegehealthpartners.com
Specializing in healthcare innovation, Imperial College Health Partners collaborates with experts to address challenges and spread innovation across the health sector |
71 | |||
| 21 |
Barclays Innovation Hub powered by Eagle Labsuk.barclays
Global fintech ecosystem facilitating innovation and growth in financial services through physical and virtual locations, events, mentoring, and digital fintech programs |
58 | |||
| 22 |
Indieindie.tech
Startup studio specializing in developing brand platforms in music and media tech Focused on creating innovative solutions in the industry |
47 | |||
| 23 |
NBT (Next Big Thing)nbtdigital.com
A global growth consultancy firm with strategic partnerships, offering services, training, and products to startups, scaleups, and enterprises worldwide |
39 | |||
| 24 |
Plus X Innovationplusxinnovation.com
The company creates collaborative workspaces and offers support to businesses focused on driving positive impact through innovative programs and events |
36 | |||
| 25 |
Seraphim Spaceseraphim.vc
Specialist investor in SpaceTech, supporting over 100 SpaceTech companies globally, making it the most prolific SpaceTech investment group. |
33 | |||
| 26 |
Coinweb Labscoinweblabs.io
A platform solving blockchain issues by creating collaborative, connected, and accessible technology for all Contact hello@coinwebio or visit wwwcoinwebio |
31 | |||
| 27 |
FinTech Innovation Lab Londonfintechinnovationlab.com
The FinTech Innovation Lab London is an accelerator program fostering collaboration between financial institutions and tech companies to develop innovative solutions |
29 | |||
| 28 |
Memcrabmemcrab.com
A turnkey Web&App solution provider specializing in eCommerce, business revenue maximization, and digital solutions for retailers, educational institutions, fintech, and banking companies |
28 | |||
| 29 |
Tenity (prev. Hackquarters)tenity.com
A startup accelerator and corporate innovation partner in London & Istanbul, supporting disruptive technologies by providing talent, support, and experience Apply/invest/support for collaboration |
28 | |||
| 30 | 
Startup Foundryorg.uk
A leading startup studio offering resources and expertise to help entrepreneurs build, launch, and grow successful startups through various services |
25 | |||
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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 11, 2026.
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