These Gauteng-based companies with in-house R&D span a range of sectors, from heavy industry to healthcare and IT. They include large established enterprises like Sasol, a global chemicals and energy company, Sappi, which provides sustainable materials from woodfibre, and Transnet Engineering, offering research, manufacturing, and maintenance services to the rail industry. Also present are research-focused organizations such as the Agricultural Research Council and The Aurum Institute, which works to eradicate TB and HIV.
A notable pattern among these firms is the concentration of headquarters in Pretoria, which hosts several key research institutions and public sector entities like the University of South Africa and the HSRC. Other major hubs include Johannesburg and Sandton, reflecting a diverse economic landscape with a strong emphasis on scientific and technological development.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 | 31,000 | ||||
| 2 |
University of South Africa/Universiteit van Suid-Afrikaunisa.ac.za
A comprehensive institution offering open learning and distance education, producing graduates who succeed with diligence, determination, and commitment, making contributions to society |
11,711 | |||
| 3 | 7,962 | ||||
| 4 |
Transnet Engineeringtransnetengineering.net
A global engineering division offering research, manufacturing, and maintenance services/products to the rail industry, with a focus on the African continent |
3,504 | |||
| 5 |
AECI Miningaecimining.com
Provider of state-of-the-art mining chemicals and explosives to optimize mineral processing and enhance safety, efficiency, and sustainability in mining operations globally |
2,463 | |||
| 6 |
Agricultural Research Councilarc.agric.za
A leading science institution conducting research, developing human capital, and fostering innovation to support and advance the agricultural sector |
2,370 | |||
| 7 |
The Aurum Institutelinktr.ee
African organization with 21 years experience leading efforts to eradicate TB and HIV through research, treatment, and collaboration with various sectors |
2,249 | |||
| 8 |
Right to Carerighttocare.org
The company provides innovative HIV/TB care, pharmacy automation, male medical circumcision, and cervical cancer diagnosis and treatment services through research-driven solutions |
1,871 | |||
| 9 |
NTT DATA Middle East and Africaservices.global.ntt
Global innovator in business and technology services, specializing in helping clients innovate, optimize, and transform through R&D investments and diverse expertise |
1,318 | |||
| 10 |
Sefako Makgatho Health Sciences Universitysmu.ac.za
Established as a health sciences university by the South African government, following the separation from the University of Limpopo based on recommendations |
1,177 | |||
| 11 |
HSRC (Human Sciences Research Council)hsrc.ac.za
The Human Sciences Research Council conducts social-scientific projects in partnership globally, with a focus on Africa, to support development and policy-making |
1,177 | |||
| 12 |
Armscorarmscor.co.za
Specializing in complex defense and security acquisition projects, research, and development solutions for all branches of the military |
1,029 | |||
| 13 |
MiX Telematicspowerfleet.com
A global provider of connected solutions for fleet management, offering safety, efficiency, sustainability, compliance, and security services to customers worldwide |
980 | |||
| 14 |
Multotec Group of Companiesmultotec.com
Specializing in beneficiation technology, Multotec Group offers customized solutions for the mining industry, focusing on reducing costs and improving efficiency through diverse product offerings |
968 | |||
| 15 |
Aberdare Cablesaberdare.co.za
A technology leader in Africa, specializing in high-tech power cables for various sectors, owned by a black economic-empowerment company, and part of a global cable manufacturer |
869 | |||
| 16 |
Mintekmintek.co.za
A leading technology organization specializing in mineral processing and extractive metallurgy, providing services, consulting, and innovative products to clients worldwide |
845 | |||
| 17 |
Vaal University of Technology (VUT)vut.ac.za
Provides advanced technical and higher education, evolving from a college to a university of technology, with multiple campuses and expansion opportunities. |
843 | |||
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. | |||||
| 18 |
MA Automotive Tool & Diegruppocln.com
Specialized in producing and assembling steel automotive parts globally, with 26 production plants and 3 R&D centers across Italy, Europe, South America, Africa, and Asia |
761 | |||
| 19 |
HENSOLDT South Africahensoldt.net
Specializing in defense and civil markets, we offer a range of electronic warfare, optronics, spectrum monitoring, and security solutions for land, sea, and air |
690 | |||
| 20 |
Flight Centre Travel Group South Africafctgcareers.com
Providing South Africans travel tips, news, giveaways, and unbeatable deals on flights, holidays, cruises, and tours through multiple booking options |
685 | |||
| 21 |
FPDfoundation.co.za
Aiming to enhance society through education, development, and community engagement, offering tailored courses, conducting research, and supporting NGOs and public sector |
663 | |||
| 22 |
Schauenburg Systemsschauenburg.co.za
An OEM delivering technology solutions for enhanced safety and productivity in mining and industrial markets, focusing on innovation and digital transformation |
618 | |||
| 23 |
WEG Africaweg.net
Global provider of industrial electrical technologies with a focus on electric motors and solutions, serving clients in Africa and worldwide |
554 | |||
| 24 |
Crown Food Groupcrownnational.co.za
Supplier of high-quality products and solutions to the food industry for over a century, with a focus on innovation, diversity, and customer satisfaction |
540 | |||
| 25 |
Denel Land Systemsdenellandsystems.co.za
Diversified high-tech industrial group under state ownership, specializing in land systems and engineering works |
456 | |||
| 26 |
MILKORmilkor.com
Specializes in providing defense solutions across air, land, sea, cyber, and weapons systems to meet national security needs |
432 | |||
| 27 |
PROXA Waterproxawater.com
A leading water treatment specialist with global reach, serving various industries with integrated solutions, innovative products, and a focus on sustainability and excellence |
428 | |||
| 28 |
Cummins Africa Middle Eastcummins.com
Design, manufacture, sales, and service of diesel engines and power generation equipment with a focus on community and technical leadership. |
393 | |||
| 29 |
Starke Ayres (Pty) Ltd.starkeayres.com
A global leader in vegetable seed development, production, and distribution with a focus on research, innovation, and quality control Passionate about customer service |
347 | |||
| 30 |
Radel (Pty) Ltdradel.co.za
Specializing in electrical, electronic, and electro-mechanical components for the vehicle industry, including railway, defence, mining, and electric vehicles since 1996 |
315 | |||
| 31 |
New Concept Mining powered by Epirocncm.co.za
Specialized in ground support solutions for underground mines, providing innovative and custom solutions for challenging mining conditions worldwide to improve safety and efficiency |
313 | |||
| 32 |
Official_Tshwane University of Technologytut.ac.za
A progressive educational institution focused on producing impactful research and equipping individuals for the future #Research #Education #InnovativeLearning |
273 | |||
| 33 |
Watercare Innovationswatercareinnovations.com
Watercare Innovations specializes in water purification solutions, offering tailored water treatment chemicals and engineered plants for potable and wastewater purification worldwide |
209 | |||
| 34 |
National Metrology Institute of South Africa (NMISA)nmisa.org
Providing South African industries with accurate measurement standards and solutions, ensuring adherence to international standards and supporting trade, quality of life, and environmental protection |
185 | |||
| 35 |
Front Runner Dometic Vehicle Outfittersdometic.com
Provider of smart and durable vehicle accessories for adventures worldwide, specializing in expedition-grade roof racks, camping gear, water solutions, and storage systems |
161 | |||
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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.
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