These companies in Ontario specialize in cybersecurity and IT services, with a strong presence in software development. They range from large established firms to mid-sized and younger companies. Notably, OpenText specializes in information management, 1Password focuses on secure access, BlackBerry provides intelligent software for enterprises, and eSentire offers managed detection and response services.
The data shows a significant concentration of these companies in the Greater Toronto Area and Waterloo, suggesting these cities are key hubs for cybersecurity and software development within Ontario. Many of these firms were founded in the early 2000s, indicating a period of growth in the sector.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 |
OpenTextopentext.com
It specializes in Information Management, assisting businesses of all sizes in securely capturing, governing, and exchanging information globally. |
22,990 | |||
| 2 |
KPMG Canadakpmg.com
Providing audit, tax, and advisory services to public, private, nonprofit, and public sector organizations across Canada with professionalism. |
10,017 | |||
| 3 |
1Password1password.com
Protects business data, employee accounts, and sensitive information with secure access, sharing, and integration into existing systems. |
3,074 | |||
| 4 |
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 | |||
| 5 |
N-able
Provides comprehensive software solutions for managed service providers, enabling remote monitoring, management, security, and data protection for their small and medium-sized business clients. |
1,341 | |||
| 6 |
BlueCatbluecatnetworks.com
Provides services and solutions for automated DDI management, network security, multicloud management, and network observability supporting cloud adoption and automation. |
728 | |||
| 7 |
eSentireesentire.com
Managed detection and response services protecting organizations worldwide from cyber threats using machine learning, threat hunting, and expert security operations. |
580 | |||
| 8 | 477 | ||||
| 9 |
Wipro Limited Canadawipro.com
Leading global IT consulting & BPO services provider using cutting-edge technologies to help clients thrive in the digital era |
464 | |||
| 10 |
Jolerajolera.com
This company offers next-generation managed services and solutions to MSPs and IT providers worldwide, with a focus on top-notch customer experience |
405 | |||
| 11 |
ADGA Groupadga.ca
Canadian defence company providing cybersecurity, simulation, systems engineering, and program management services for government and industry clients. |
330 | |||
| 12 |
Tailscaletailscale.com
Tailscale offers secure, private networks for teams with quick setup, low latency, and compatibility with existing services, replacing traditional corporate VPNs |
326 | |||
| 13 |
Calian IT & Cyber Solutionscalian.com
Global provider of IT & Cyber Solutions, digital healthcare, and application modernization Offering proactive, scalable solutions to drive innovation for various industries |
230 | |||
| 14 |
Field Effectfieldeffect.com
Cyber security company providing threat detection, monitoring, training, and compliance solutions for small and mid-size businesses with sophisticated technology and actionable insights |
151 | |||
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. | |||||
| 15 |
IT Weaponsitweapons.ca
Provider of IT services, hybrid cloud solutions, information security, connectivity, infrastructure management, and technical support to streamline and optimize technology environments for businesses |
109 | |||
| 16 |
Bell Cyberbusiness.bell.ca
Next-generation managed security services provider, driving superior cybersecurity outcomes through an innovative "Security-as-a-Service" model, leveraging a cybersecurity mesh architecture. |
109 | |||
| 17 |
AllHeart Weballheartweb.com
A global AI-driven company offers user-friendly datasets, cybersecurity solutions, lead generation services, and digital visibility enhancement to clients worldwide |
52 | |||
| 18 |
AUGMENTTaugmentt.com
Centralized SaaS security platform for MSPs to deliver managed security services for Microsoft and cloud apps, offering visibility, protection, and threat detection |
44 | |||
| 19 |
Audcompaudcomp.com
A Canadian IT solutions provider offering managed services, cloud services, IT infrastructure, data storage, networking, software, procurement, and professional services |
34 | |||
| 20 |
CyBeatscybeats.com
Leader in software supply chain security, offering continuous end-to-end protection for software and devices with proactive threat prevention and quick vulnerability response |
32 | |||
| 21 |
IAMConceptsiamconcepts.ca
A Canadian cybersecurity consulting firm specializing in Enterprise Identity and Access Management solutions for clients in Canada, the US, and Europe |
20 | |||
| 22 |
KTIkearnstechnology.com
A managed services company and hardware supplier with a team of advanced developers specializing in machine learning, databases, cloud-based solutions, and design |
17 | |||
| 23 |
Autohostautohost.ai
Specializing in identity verification and fraud prevention solutions for the sharing economy, we use machine learning and behavioral checks to protect businesses against chargebacks and fraud |
12 | |||
| 24 |
Megawiremegawire.com
Industry-leading provider of managed IT services in Southern Ontario, offering customized solutions for businesses of all sizes with a comprehensive background in networking, storage, and virtualization |
10 | |||
| 25 |
OwlEyeowleye.com
A pioneer in manual secure code review services, leveraging security analysts to identify and address vulnerabilities in application source code |
7 | |||
| 26 |
VNK CYBER SECURITY AND INTELLIGENCE (VNK CSI)vnkcsi.com
Providing SaaS-based cybersecurity solutions, we protect businesses from cyber threats, allowing them to focus on core competencies in a secure digital environment |
5 | |||
| 27 |
SinghIT Services Inc.singhit.ca
Offering comprehensive IT solutions, including managed services, web services, IT security, and infrastructure planning and deployment, with a focus on client care |
3 | |||
| 28 |
Telemerge are now New Era Technology VCD, CA, Incneweratech.com
Global provider of managed technology solutions with expertise in collaboration, networking, security, cloud, and professional services across various industries worldwide |
2 | |||
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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 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
- Companies with in-house R&D in Ontario 300
- Logistics companies in Ontario 285
- Education providers in Ontario 276
- SaaS companies in Ontario 275
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- Public sector organisations in Ontario 259
- Financial Services companies in Ontario 250
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- Healthcare providers in Ontario 226
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- Professional services firms in Ontario 211
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- 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