This selection of large companies in Ontario primarily features automotive manufacturers and suppliers. Key players include Magna International, a developer of vehicle technologies and systems; Linamar Corporation, an advanced manufacturing company specializing in vehicle solutions; and Martinrea International, a global automotive supplier focusing on metal forming and fluid systems. Other notable firms are ABC Technologies, a leader in plastics and injection molding for the automotive industry, and Toyota Motor Manufacturing Canada, a large-scale vehicle assembly operation.
A significant pattern among these companies is their strong concentration in the automotive sector, encompassing both vehicle production and the supply of specialized components and technologies. While most are directly involved in motor vehicle manufacturing, related industries such as automation machinery manufacturing, urban transit services, financial services for fleets, and even software development (BlackBerry) also appear, often serving the broader mobility ecosystem.
| # | 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 |
Toronto Transit Commission (TTC)ttc.ca
A leading transit system in Toronto, providing safe and reliable transportation to over 17 million customers daily through various modes |
8,829 | |||
| 3 |
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 | |||
| 4 |
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 | |||
| 5 |
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 | |||
| 6 |
Toyota Motor Manufacturing Canadatmmc.ca
Large-scale vehicle assembly operation in Ontario with multiple production lines, employing thousands and focusing on quality and community responsibility. |
2,658 | |||
| 7 |
Multimaticmultimatic.com
A global enterprise specializing in supplying automotive components, systems, and engineering services with manufacturing divisions and engineering facilities worldwide |
2,598 | |||
| 8 |
Element Fleet Managementelementfleet.com
Providing tailored fleet management solutions and expert support to reduce costs and simplify business operations across entire fleet lifecycles. |
2,504 | |||
| 9 |
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 | |||
| 10 |
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 | |||
| 11 |
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 | |||
| 12 |
Honda of Canada Mfg.ca.indeed.com
Manufactures high-quality Honda vehicles in Canada for Canadian and US markets, with a focus on growth, innovation, and skilled associates |
1,700 | |||
| 13 |
Honda Canada Inc.hondacanada.ca
A Canadian success story in manufacturing vehicles and power equipment, with a commitment to sourcing from Canadian suppliers and sustainable practices |
1,540 | |||
| 14 |
Toyota Canada Inc.toyota.ca
Exclusive distributor of Toyota and Lexus vehicles in Canada, operating regional offices, parts centers, and manufacturing plants in Ontario. |
1,210 | |||
| 15 |
Valiant TMSvalianttms.com
An Industry 40 system integrator specializing in digitalization, process development, design, and technology integration with global strategic teams |
1,105 | |||
| 16 |
Mercedes-Benz Canadamercedes-benz.ca
Distributor and marketer of luxury vehicles, including combustion, hybrid, and electric models, as well as vans, with headquarters in Mississauga, Ontario |
1,014 | |||
| 17 |
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 | |||
| 18 |
Ground Effects Ltd.gfxltd.com
A manufacturer of OEM-level automotive accessories that started in Canada and now has nearly 40 locations worldwide |
862 | |||
| 19 |
MacLean Engineeringmacleanengineering.com
Specializing in underground mobile equipment for hard rock mining, offering a wide range of solutions worldwide, including electrification for diesel-free operations |
779 | |||
| 20 |
Stackpole Internationaljohnsonelectric.com
Global solutions provider specializing in fluid power systems and powder metal technology, offering high-quality, high-performance components and systems for various applications worldwide |
774 | |||
| 21 |
Litens Automotive Grouplitens.com
Innovative global automotive leader with patented powertrain solutions, committed to excellence, diverse and inclusive workplace fostering creativity and innovation |
726 | |||
| 22 |
NextStar Energy
Canada's pioneering producer of electric vehicle batteries, partnering with Stellantis and LG Energy Solution for innovative manufacturing |
680 | |||
| 23 |
Mitchell Plasticsmitchellplastics.com
Leading tier one supplier of automotive interior mechanisms and decorative components, offering concept, design, development, testing, and validation services with in-house manufacturing capabilities for quality products |
590 | |||
| 24 |
Kia Canadakia.ca
Innovative, dynamic, and award-winning products and services offered through a network of dealers across Canada, dedicated to inspiring consumers |
581 | |||
| 25 |
Vuteq Canada Incvuteq.ca
An international corporation with operations in automotive manufacturing, glass manufacturing, food production, and more, committed to continuous improvement and community involvement |
572 | |||
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. | |||||
| 26 |
Matcor-Matsu Groupmatcor-matsu.com
Fully integrated supplier of engineering and manufacturing services for automotive OEMs, specializing in complex assemblies and stampings for various applications |
556 | |||
| 27 |
Meridian Lightweight Technologies Inc.meridian-mag.com
Innovative supplier of magnesium die casting components and assemblies for the transportation market, emphasizing design excellence and global client base expansion |
555 | |||
| 28 |
OC Transpooctranspo.com
Public transportation provider in Canada's national capital with a fleet of accessible buses and trains, focused on sustainability and expanding light rail system |
553 | |||
| 29 |
KSR International Inc.ksrint.com
Industry leader in designing, engineering, and manufacturing driver interface systems for Tier 1 OEMs with a rich history of reliable manufacturing |
552 | |||
| 30 |
TG Minto Corporationtgminto.com
A company with a heritage of innovation and leadership, focused on achieving manufacturing superiority through world-class processes and product quality |
535 | |||
| 31 |
Volkswagen Group Canada Inc.vwgoa.taleo.net
Global distributor of automobile and automotive products, part of Volkswagen Group, supporting dealers across Canada with national operations and training |
527 | |||
| 32 |
Mazda Canada Incmazda.ca
Distribution of automobiles and automotive parts in Canada, fostering teamwork and growth within a dynamic and challenging environment. |
476 | |||
| 33 |
IMT Groupimtcorporation.com
A leading manufacturer and supplier to various industries, offering closed-die forged components, product innovation, advanced technology, and quality assurance processes |
476 | |||
| 34 |
Hyundai Auto Canada Corp.hyundaicanada.com
A subsidiary of Hyundai Motor Company, this Canadian company markets a full line-up of award-winning vehicles committed to quality, safety, and design |
467 | |||
| 35 |
THK Rhythm Automotivethk-rhythm-auto.com
Designs and manufactures linkage and suspension products using high strength materials for optimal performance and fuel efficiency |
446 | |||
| 36 |
Sharp Bus Lines Limitedsharpbus.com
A leading transportation provider in Southern Ontario offering school bus services with a focus on trust, reliability, integrity, and safety Apply to join their team today |
421 | |||
| 37 |
Mevotechmevotech.com
A North American leader in engineering and designing driveline, steering, and suspension aftermarket auto parts with a focus on customer service, innovation, and collaboration |
413 | |||
| 38 |
Mobile Climate Controlmcc-hvac.com
Specializing in custom engineered HVAC systems for commercial vehicles worldwide, providing optimal climate comfort solutions through strong engineering expertise |
408 | |||
| 39 |
Subaru Canada Incsubaru.ca
A subsidiary of Subaru Corporation, the company has been importing and selling Subaru vehicles in Canada since 1978, with significant growth in sales |
387 | |||
| 40 |
Toyota Boshoku Canada, Inc.toyotaboshoku.ca
Manufactures automotive components for Toyota, specializing in creating innovative interior spaces that exceed customer expectations through quality craftsmanship and efficiency |
383 | |||
| 41 |
MetriCan Group of Companiesmetrican.com
A leading supplier of tooling, value-added assembly, and stamped metal components for automotive manufacturing, focusing on quality, efficiency, and customer-centric solutions |
357 | |||
| 42 |
INOAC Exterior Systems Inc.
Specializing in supplying painted exterior trim products for the automotive industry, focusing on automotive exterior parts |
354 | |||
| 43 |
Wescast Industries Inc.wescast.com
Designs, casts, machines, and assembles exhaust system components including manifolds and turbo charger housings for global automotive manufacturers and Tier 1 suppliers. |
350 | |||
| 44 |
Switzer-CARTY Transportationswitzer-carty.com
A premier school bus transportation and charter bus rental company in Ontario, Canada, focused on delivering safe, secure, and reliable services |
340 | |||
| 45 |
CpK Interior Products Inc.cpkip.com
A global leader in interior products, specializing in precision manufacturing and innovative solutions for original equipment manufacturers and Tier One suppliers |
334 | |||
| 46 |
Jefferson Elora Corporationca.indeed.com
An auto-parts manufacturer specializing in Metal Stamping and Robotic Welding, committed to delivering high-quality products at low cost Hiring Production Associates |
329 | |||
| 47 |
AirBoss of Americaairboss.com
A group of businesses specializing in rubber compounding, engineering, and military products, offering innovative solutions and high-quality rubber products for various applications |
327 | |||
| 48 |
Simcoe Parts Service Inc.simcoeparts.com
Premier logistics supplier based in Ontario, focusing on world-class management services with high standards in quality, cost, delivery, safety, and environment Email for job opportunities |
322 | |||
| 49 | 319 | ||||
| 50 |
Marwood International Inc.marwoodinternational.com
An award-winning team specializing in structural components and modular assemblies for the automotive industry, offering quality products and responsive customer service |
310 | |||
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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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