This selection of companies in Ontario highlights organizations with substantial in-house R&D capabilities, primarily large enterprises and institutions. It features major players across several sectors, including Magna International, which develops technologies for safer and cleaner vehicles; Thomson Reuters, providing information tools for legal and tax professionals; Shopify, offering e-commerce solutions; and OpenText, specializing in information management. The list also includes prominent educational and healthcare institutions like the University of Toronto and University Health Network.
A notable pattern among these R&D-focused entities is the strong presence of Toronto as a headquarters city, alongside other key locations such as Ottawa, Aurora, and Waterloo. This suggests a concentration of research and development activities within the province's major urban centers, spanning manufacturing, software development, higher education, and healthcare.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 |
Magna Internationalmagna.com
Developing technologies and systems to make vehicles safer and cleaner, focusing on community, environmental, and human benefits. |
158,000 | |||
| 2 |
Thomson Reutersthomsonreuters.com
It offers news and information tools for professionals in legal, regulatory, and tax sectors, helping them navigate complex environments. |
36,640 | |||
| 3 |
University of Torontodefygravitycampaign.utoronto.ca
Leading Canadian university focused on research, innovation, and global education to address pressing societal challenges and prepare students for success |
28,832 | |||
| 4 |
Shopifyshopify.com
Provides trusted tools to start, grow, market, and manage a retail business of any size, powering millions of businesses across 175 countries. |
28,526 | |||
| 5 |
OpenTextopentext.com
It specializes in Information Management, assisting businesses of all sizes in securely capturing, governing, and exchanging information globally. |
22,990 | |||
| 6 |
Celesticacelestica.com
Global leader in providing design, manufacturing, and supply chain solutions for aerospace, defense, communications, healthtech, and more, delivering innovative solutions for complex challenges |
16,022 | |||
| 7 |
University of Ottawauottawa.ca
The company is the largest bilingual university in the world, offering education in English and French with a focus on research and global advancements |
12,220 | |||
| 8 |
University Health Networkuhn.ca
Largest Canadian research hospital network specializing in patient care, medical research, education, and fundraising for advanced healthcare services. |
11,930 | |||
| 9 |
Ontario Power Generationopg.com
Leading clean power generator advancing clean energy innovations, striving for a net-zero future with diverse electricity generation fleet in Ontario and the United States |
9,878 | |||
| 10 |
Unity Health Torontounityhealth.to
A health network in Toronto providing primary, community, specialized, and long-term care services, as well as investing in research and education |
8,686 | |||
| 11 |
The Hospital for Sick Childrensickkids.ca
Leading pediatric hospital integrating patient care, research, and education to advance children's health and develop innovative treatments globally. |
8,636 | |||
| 12 |
Toronto Metropolitan Universitytorontomu.ca
Innovative urban university in Toronto, focusing on creativity, entrepreneurship, inclusivity, and global community engagement to serve societal needs |
8,478 | |||
| 13 |
University of Guelphuoguelph.ca
Dedicated to improving quality of life through innovative research and education in essential areas like water, food, health, and environment |
7,725 | |||
| 14 |
The Ottawa Hospitalottawahospital.on.ca
Innovative teaching and research hospital providing specialized care, developing new treatments, and improving patient care through community engagement and global impact |
7,679 | |||
| 15 |
Sunnybrooksunnybrook.ca
A leading teaching hospital affiliated with the University of Toronto, specializing in patient care, groundbreaking research, and inventing the future of healthcare |
7,599 | |||
| 16 |
London Health Sciences Centre (LHSC)lhsc.on.ca
Acute care teaching hospital offering specialized clinical services, leading in discovery and innovation, providing exceptional patient care and training healthcare professionals |
7,092 | |||
| 17 |
Hamilton Health Scienceshamiltonhealthsciences.ca
Healthcare organization delivering specialized cardiac, stroke, trauma, cancer, palliative, and pediatric care to southwestern Ontario and beyond. |
6,690 | |||
| 18 |
Linamar Corporationlinktr.ee
Advanced manufacturing company specializing in solutions for vehicles, motion, work, and lives Comprised of Industrial and Mobility segments, with global reach and innovative products |
6,668 | |||
| 19 |
Apotex Inc.apotex.com
A global pharmaceutical company producing affordable high-quality medicines, with divisions focusing on generics, biosimilars, consumer products, and API manufacturing |
6,548 | |||
| 20 |
Martinrea Internationalmartinrea.com
Global automotive supplier focused on metal forming, aluminum casting, fluid systems, and assemblies to meet lightweight requirements Employs 18,000 people worldwide |
5,692 | |||
| 21 |
Fisheries and Oceans Canada / Pêches et Océans Canadadfo-mpo.gc.ca
Manage fisheries and aquaculture sustainably, protect aquatic ecosystems, maintain navigable waterways, and respond to maritime emergencies with Indigenous collaboration. |
5,665 | |||
| 22 |
ATS Corporationatsautomation.com
A manufacturing solutions provider with global capabilities, specializing in custom automation systems for industries such as life sciences, food & beverage, transportation, and energy |
5,287 | |||
| 23 |
Conestoga Collegeconestogac.on.ca
career-focused education, training, applied research, technology-enhanced learning, co-op opportunities, and comprehensive student support for diverse learners. |
5,198 | |||
| 24 |
Sheridan Collegesheridancollege.ca
Established in 1967, this institution has grown to become a leading Ontario postsecondary institution with four campuses and a diverse range of programs |
5,079 | |||
| 25 |
St. Michael's Hospitalunityhealth.to
A leading hospital providing compassionate care, medical education in 27 disciplines, and research through the Keenan Research Centre for global impact |
4,868 | |||
| 26 |
Natural Resources Canada (NRCan)natural-resources.canada.ca
A department of the Government of Canada focused on advancing sustainable resource management, economic growth, and environmental stewardship through innovative policies and programs |
4,579 | |||
| 27 | 4,478 | ||||
| 28 | 4,477 | ||||
| 29 |
LifeLabs Medical Laboratory Serviceslifelabs.com
A leading Canadian provider of diagnostic information and digital health systems, offering laboratory tests, genetics services, and online patient portals |
4,356 | |||
| 30 |
William Osler Health Systemwilliamoslerhs.ca
Health system with three hospitals serving 13 million residents, providing a wide range of services including inpatient, outpatient, urgent care, and specialty clinics |
4,350 | |||
| 31 |
University of Windsoruwindsor.ca
A student-focused university offering undergraduate and graduate programs, professional schools, and innovative research facilities, promoting diversity and excellence in education |
4,284 | |||
| 32 |
Sinai Healthsinaihealth.ca
A leading academic health science centre focused on integrated care, innovative research, and educating future healthcare leaders for comprehensive patient care |
4,083 | |||
| 33 |
ABC Technologiesabctechnologies.com
A global leader in plastics and injection molding technology for the automotive industry, focusing on innovation, sustainability, and creating career opportunities |
4,059 | |||
| 34 |
Lakeridge Healthlakeridgehealth.on.ca
A comprehensive healthcare provider with multiple hospitals, specialty centers, and community services, committed to delivering high-quality care to the region |
3,760 | |||
| 35 |
CSA Testing & Certificationcsagroup.org
Development of safety and technical standards combined with global testing, inspection, and certification services for diverse industries. |
3,522 | |||
| 36 |
Durham Collegedurhamcollege.ca
Durham College offers full-time and part-time programs in various disciplines to over 12,000 students, including a new health care technology management degree program |
3,210 | |||
| 37 |
Geotabgeotab.com
Provides connected vehicle, asset management solutions. Leverages data analytics, AI to transform fleet performance, operations, reducing costs, driving efficiency for over 55,000 customers. |
3,167 | |||
| 38 |
ArcelorMittal Dofascodofasco.arcelormittal.com
Leading manufacturer in North America's supply chain, producing sustainable steel products for automotive, energy, packaging, and construction industries, prioritizing employees and community engagement |
3,136 | |||
| 39 |
1Password1password.com
Protects business data, employee accounts, and sensitive information with secure access, sharing, and integration into existing systems. |
3,074 | |||
| 40 |
St. Joseph's Healthcare Hamiltonstjoes.ca
A values-based academic health science centre affiliated with McMaster University and Mohawk College, committed to providing integrated, compassionate care and advancing research and education |
2,983 | |||
| 41 |
Conestoga Collegeon.ca
A leader in polytechnic education offering career-focused programs, engineering degrees, and support services while promoting economic prosperity and student success |
2,968 | |||
| 42 |
Mount Sinai Hospital (Toronto), Sinai Healthmountsinai.on.ca
Internationally recognized academic health sciences center providing exemplary patient care, nursing excellence, and top employer culture Flagship clinical programs available |
2,951 | |||
| 43 |
North York General Hospitalnygh.on.ca
A leading community academic hospital in Canada offering a wide range of acute, ambulatory, and long-term care services with a focus on patient- and family-centered care |
2,917 | |||
| 44 | 2,851 | ||||
| 45 |
Kingston Health Sciences Centrekingstonhsc.ca
Top Canadian hospital, advancing health care through patient care, medical research, and training future healthcare professionals for Southeastern Ontario. |
2,793 | |||
| 46 |
CHEOcheo.on.ca
A global leader in pediatric health care and research, providing excellence in complex care, education, and community partnership for children and youth |
2,784 | |||
| 47 |
Niagara Collegeniagaracollege.ca
Leader in applied education and training, established in 1967 in Welland and now expanding across the Niagara region for top student satisfaction |
2,686 | |||
| 48 |
Multimaticmultimatic.com
A global enterprise specializing in supplying automotive components, systems, and engineering services with manufacturing divisions and engineering facilities worldwide |
2,598 | |||
| 49 |
Canadian Nuclear Laboratoriescnl.ca
A leading organization in nuclear science and technology, specializing in research, development, engineering, waste management, and decommissioning services for various applications |
2,340 | |||
| 50 |
Kinaxiskinaxis.com
Empowering businesses to orchestrate their entire supply chain network, from long-term planning to real-time execution and delivery. |
2,322 | |||
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. | |||||
| 51 |
Woodbridgewoodbridgegroup.com
Global provider of innovative solutions for automotive, commercial, recreational, packaging, healthcare, and building industries with headquarters in Canada and the USA |
2,262 | |||
| 52 |
Canadian Solar Inc.csisolar.com
Global manufacturer of photovoltaic modules and inverters developing utility-scale solar power and battery energy storage projects with over 165 GW delivered worldwide. |
2,240 | |||
| 53 |
Lallemandlallemandplantcare.com
A global leader in yeast and bacterial products, focusing on natural fermentation processes in agri-food industries, with opportunities for growth and innovation |
2,232 | |||
| 54 | 2,224 | ||||
| 55 |
Michael Garron Hospitaltehn.ca
A vibrant community hospital in East Toronto providing high-quality, patient-centred healthcare services along the continuum of care with strong partnerships |
2,219 | |||
| 56 |
FGF Brandsfgfbrands.com
Innovative technology-driven bakery pushing boundaries with sustainable ingredients, creating delicious baked goods and disrupting the global food industry for the better |
2,195 | |||
| 57 |
Royal Victoria Regional Health Centrervh.on.ca
Healthcare institution in Barrie, Ontario serving over 450,000 residents with specialized services like interventional radiology, stroke care, trauma, cancer, heart, child, and youth programs |
2,191 | |||
| 58 |
Give and Go Prepared Foodsgiveandgo.com
A leading manufacturer of sweet baked goods, offering indulgent treats under various brands, with a focus on innovation and quality for global retailers |
2,143 | |||
| 59 |
IPEX by Aliaxisipexna.com
The company prioritizes honesty, fairness, integrity, and customer satisfaction through a customer-first culture, innovation, and long-term thinking in business |
2,085 | |||
| 60 |
Colas Canada Inc.colas.com
A leading company in construction and maintenance of transportation infrastructure across Canada, part of a global group with operations worldwide |
2,065 | |||
| 61 |
Magellan Aerospace Limitedmagellan.aero
Designs and manufactures aeroengine and aerostructure components, advanced military and space products, plus engine repair and overhaul services globally. |
2,050 | |||
| 62 |
BlackBerryblackberry.com
Provides intelligent software and services to enterprises and governments, enabling transformative applications, new revenue streams, and innovative business models with safety, security, and reliability. |
2,005 | |||
| 63 |
Petro-Canada Lubricantspetrocanadalubricants.com
The company supplies over 350 high-performance lubricants, fluids, and greases worldwide, catering to a variety of industries and applications to optimize equipment performance and reliability |
1,799 | |||
| 64 |
Huawei Canadaconsumer.huawei.com
A global provider of ICT infrastructure and smart devices, committed to connecting the world through innovative research and development in Canada |
1,758 | |||
| 65 |
Health Sciences North/Horizon Santé-Nordhsnsudbury.ca
An integrated network providing high-quality patient care, research, teaching, and services in various medical specialties to communities in Northern Ontario |
1,755 | |||
| 66 |
Plasmanplasman.com
Global leader in automotive components, offering single-source solutions for tooling, injection molding, chroming, and assembly with a collaborative mindset and unrivaled dedication |
1,751 | |||
| 67 |
Fleming Collegeflemingcollege.ca
Fleming College offers personalized learning and support in various fields, fostering innovation and sustainability for students, communities, and the environment |
1,746 | |||
| 68 |
St. Joseph's Health Care Londonsjhc.london.on.ca
A leading academic health care organization in Canada providing compassionate care, teaching, and research to help people live life fully |
1,707 | |||
| 69 |
Lambton Collegelambtoncollege.ca
Provincial leader in education, training, and research, aligning programs with industry needs to provide students with experiential learning opportunities for success |
1,701 | |||
| 70 |
Thunder Bay Regional Health Sciences Centretbrhsc.net
An academic health sciences centre providing comprehensive care, medical research, and training for healthcare providers in a region the size of France |
1,655 | |||
| 71 |
Ross Videorossvideo.com
Designs and manufactures innovative live production equipment used globally by broadcasters, sports venues, government, and production companies. |
1,614 | |||
| 72 | 1,450 | ||||
| 73 |
Evertzevertz.com
Leading global manufacturer of broadcast equipment and solutions for content creation, distribution, and delivery across various platforms and sectors worldwide. |
1,436 | |||
| 74 |
Baycrestbaycrest.org
Global leader in aging and brain health innovations, offering comprehensive care for aging patients, conducting top research in cognitive neuroscience, and promoting global knowledge exchange |
1,407 | |||
| 75 |
Kinectricskinectrics.com
Integrated lifecycle management services for electric power industry worldwide Testing, inspection, certification, engineering consulting, and maintenance services to ensure safe and efficient utility asset performance |
1,361 | |||
| 76 |
OCAD Universityocadu.ca
A leading institution in Canada, specializing in art and design education for aspiring students to excel in their creative pursuits |
1,343 | |||
| 77 |
DECIEM | THE ABNORMAL BEAUTY COMPANYdeciem.com
A beauty brand umbrella offering high-quality, transparent skincare products, founded by a disrupter aiming to redefine beauty industry standards |
1,311 | |||
| 78 |
Bruyère Healthbruyere.org
The company provides a range of health care services including rehabilitation, complex care, family health teams, long-term care, and senior living options Their mission is to enhance quality of life through integrated care |
1,298 | |||
| 79 | 1,271 | ||||
| 80 |
General Dynamics Mission Systems–Canadagdmissionsystems.ca
A leading Canadian defense and security technology organization, focused on innovation, community involvement, and supporting military needs worldwide |
1,270 | |||
| 81 |
Tenstorrenttenstorrent.com
Tenstorrent builds next-generation AI computers, combining expertise in computer architecture, ASIC design, systems, and neural network compilers Offices worldwide Join our team! |
1,226 | |||
| 82 |
Armstrong Fluid Technologyarmstrongfluidtechnology.com
A global leader in intelligent fluid flow equipment and optimization technologies, focusing on HVAC, plumbing, gas transmission, and fire safety applications |
1,224 | |||
| 83 |
Women's College Hospitalwomenscollegehospital.ca
A pioneering healthcare institution focusing on women's health, innovation, and addressing Canada's healthcare challenges through interdisciplinary teams and equitable work environment |
1,200 | |||
| 84 |
Candu Energy Inc.snclavalin.com
A leading developer of CANDU® reactors, providing clean and reliable electricity solutions internationally while meeting top safety and regulatory standards |
1,187 | |||
| 85 |
Valiant TMSvalianttms.com
An Industry 40 system integrator specializing in digitalization, process development, design, and technology integration with global strategic teams |
1,105 | |||
| 86 |
University of Ottawa Heart Instituteottawaheart.ca
A leading cardiovascular health center in Canada providing high-tech, personalized care, advancing cardiac medicine through research, and pioneering new treatments globally |
1,087 | |||
| 87 |
Holland Bloorview Kids Rehabilitation Hospitalhollandbloorview.ca
Pioneering treatments, technologies, and programs for children with disabilities to fully participate in life through a world-class teaching hospital |
1,086 | |||
| 88 |
Coherecohere.com
Building cutting-edge foundation models and end-to-end AI products for businesses, with a focus on data security and privacy across various deployment options. |
1,020 | |||
| 89 |
Docebodocebo.com
Provides a comprehensive learning platform that enables organizations to deliver personalized training and measure the effectiveness of their learning initiatives. |
1,016 | |||
| 90 |
Brock Solutionsbrocksolutions.com
Global industrial automation and professional services provider specializing in Manufacturing, Transportation, and Utilities with expertise in engineering software and solutions |
976 | |||
| 91 |
Sherritt International Corporationsherritt.com
A global leader in mining nickel and cobalt, creating innovative environmental solutions for oil and mining industries, and a major energy producer |
934 | |||
| 92 |
Canadian Bank Note Company, Limitedcbnco.com
The company specializes in providing secure identification solutions, including currency, passports, driver licenses, and biometric solutions, to prevent fraud globally |
925 | |||
| 93 |
The Woodbridge Groupwoodbridgegroup.com
Innovative urethane and bead foam technologies for automotive and other industries worldwide, providing comfort, safety, acoustics, insulation, and structural solutions Offering diverse services |
915 | |||
| 94 |
Temerty Faculty of Medicine, University of Torontotemertymedicine.utoronto.ca
Leader in medical research and innovation, collaborating with diverse partners to address global health challenges for over a century |
913 | |||
| 95 |
Princess Margaret Cancer Centreuhn.ca
Keep up-to-date on the latest developments and changes at a prominent hospital through news articles and general information |
898 | |||
| 96 |
Providence Careprovidencecare.ca
Leading provider of specialized care in aging, mental health, and rehabilitation, offering hospital, long-term care, hospice, and community-based services with a focus on independence and quality of life |
898 | |||
| 97 | 870 | ||||
| 98 |
Coritycority.com
Empowering employees with EHS software solutions to reduce risks, improve efficiencies, and create a safer, healthier, and more sustainable world |
864 | |||
| 99 |
Teledyne DALSAteledynedalsa.com
Specialized in high-performance image sensing, semiconductor fabrication, and 3D geospatial systems with global R&D and support locations. |
863 | |||
| 100 |
Ground Effects Ltd.gfxltd.com
A manufacturer of OEM-level automotive accessories that started in Canada and now has nearly 40 locations worldwide |
862 | |||
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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 12, 2026.
More company lists in Ontario
- The largest companies in Ontario 5,032
- Multinational companies in Ontario 901
- Financial services firms in Ontario 396
- Manufacturers in Ontario 389
- Critical infrastructure operators in Ontario 344
- Retail chains in Ontario 327
- Logistics companies in Ontario 285
- Education providers in Ontario 276
- SaaS companies in Ontario 275
- Truck Transportation companies in Ontario 270
- Transportation, Logistics, Supply Chain and Storage companies in Ontario 261
- Public sector organisations in Ontario 259
- Financial Services companies in Ontario 250
- IT Services and IT Consulting companies in Ontario 235
- Software Development companies in Ontario 231
- Healthcare providers in Ontario 226
- Hardware manufacturers in Ontario 213
- Professional services firms in Ontario 211
- Hospitals and Health Care companies in Ontario 205
- Distributors and wholesalers in Ontario 183
- Companies with a mobile app in Ontario 181
- Publicly traded companies in Ontario 156
- IT services companies in Ontario 156
- Subscription businesses in Ontario 153
The same list elsewhere in Canada
- Companies with in-house R&D in Canada 678
- Companies with in-house R&D in the province of Quebec 159
- Companies with in-house R&D in British Columbia 76
- Companies with in-house R&D in Alberta 74
- Companies with in-house R&D in Toronto 93
- Companies with in-house R&D in Montreal 59
- Companies with in-house R&D in Calgary 39
- Companies with in-house R&D in Vancouver 34