These Ontario-based firms are primarily large law practices, with one financial services firm and one software development company also present. Notable examples include Fasken, an international law firm with over 950 lawyers, and Borden Ladner Gervais LLP, a Canadian law firm offering bilingual services. McCarthy Tétrault provides a wide range of legal services to Canadian and international clients, while Osler, Hoskin & Harcourt LLP advises on business law.
A clear pattern among these companies is their strong concentration in Toronto, which serves as the headquarters for all listed firms. Many of these law firms also have long histories, with Borden Ladner Gervais LLP founded in 1823, McCarthy Tétrault in 1855, and Blake, Cassels & Graydon LLP in 1856, indicating a well-established legal sector.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 |
KPMG Canadakpmg.com
Providing audit, tax, and advisory services to public, private, nonprofit, and public sector organizations across Canada with professionalism. |
10,017 | |||
| 2 |
Faskenfasken.com
An international law firm with over 950 lawyers and offices on three continents, providing practical legal services for complex business and litigation challenges |
2,458 | |||
| 3 |
Borden Ladner Gervais LLP (BLG)blg.com
A Canadian law firm offering bilingual services in common and civil law, with a national presence and global reach through an international network Contributing to communities through pro bono work and charitable initiatives |
2,290 | |||
| 4 |
McCarthy Tétraultmccarthy.ca
Canadian-based law firm offering a wide range of legal services to Canadian and international clients, with expertise in business law, litigation, tax, real estate, and labor law |
2,088 | |||
| 5 |
Osler, Hoskin & Harcourt LLPosler.com
providing business law advice and counsel to Canadian, U.S., and international clients on domestic and cross-border legal issues |
1,707 | |||
| 6 |
Blake, Cassels & Graydon LLPblakes.com
A top Canadian business law firm providing exceptional legal services to leading businesses in Canada and globally, with a focus on client relationships and expertise |
1,686 | |||
| 7 |
Gowling WLG Canadagowlingwlg.com
International legal organization formed through the merger of a Canadian and UK-based law firm, offering specialized legal services across 18 global locations |
1,572 | |||
| 8 |
Stikeman Elliott LLPstikeman.com
A global leader in Canadian business law, providing legal services and creative solutions in various practice areas to clients worldwide |
1,564 | |||
| 9 |
Miller Thomson LLPmillerthomson.com
National business law firm with 525 lawyers in Canada offering litigation, mergers and acquisitions, corporate finance, tax, real estate, labor & employment services |
1,415 | |||
| 10 | 1,106 | ||||
| 11 |
Legal Aid Ontariolegalaid.on.ca
Legal Aid Ontario provides high-quality legal services to low-income individuals, including advice, duty counsel representation, and funding for complex cases |
1,063 | |||
| 12 |
Dye & Durham Corporationdyedurham.com
Provider of practice management solutions for legal professionals, data insights for corporate transactions, and payments infrastructure for government and financial institutions across multiple countries |
945 | |||
| 13 |
McMillan LLPmcmillan.ca
A national business law firm in Canada specializing in transportation, technology, infrastructure, natural resources, energy, cross-border transactions, private equity, real estate, and regulatory disputes |
935 | |||
| 14 |
Cassels Brock & Blackwell LLPcassels.com
A leading Canadian law practice specializing in business law, serving clients ranging from start-ups to multinational corporations with practical and flexible legal solutions |
874 | |||
| 15 |
Davies Ward Phillips & Vineberg LLPdwpv.com
A leading Canadian business law firm specializing in high-stakes matters, providing clarity, speed, and effective solutions for complex deals and cases Offices in Toronto, Montréal, and New York |
807 | |||
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| 16 |
Law Society of Ontariolso.ca
Regulating, licensing, and disciplining lawyers and paralegals in Ontario to ensure high standards of learning, competence, and professional conduct |
788 | |||
| 17 |
Aird & Berlis LLPairdberlis.com
Legal counsel with a business perspective for clients conducting business in Canada or abroad, with strong relationships and expertise in various industries |
643 | |||
| 18 |
Goodmans LLPgoodmans.ca
A leading Canadian law firm with expertise in business law, litigation, public/private sectors, providing innovative solutions for clients' success |
520 | |||
| 19 |
Smart & Biggarsmartbiggar.ca
Leading Canadian firm specializing in intellectual property law with a team of over 100 lawyers, patent agents, and trademark agents providing top-quality advisory services and successful IP litigation outcomes |
505 | |||
| 20 |
Canadian Medical Protective Associationcmpa-acpm.ca
A leading provider of medical liability protection and professional development for Canadian physicians, offering risk management education and legal advice |
481 | |||
| 21 |
Lerners LLPlerners.ca
Law firm with over 100 lawyers offering expertise in various practice areas, known for handling complex cases, creating new law, and delivering positive outcomes for clients |
464 | |||
| 22 |
Blaney McMurtry LLPblaney.com
A premier law firm in Toronto's financial district, specializing in litigation, real estate, and business law with a focus on delivering efficient and practical legal services |
327 | |||
| 23 |
Tribunals Ontario I Tribunaux décisionnels Ontariotribunalsontario.ca
Group of 13 adjudicative tribunals in Ontario providing fair and accessible dispute resolution to thousands of Ontarians, resolving nearly 100,000 cases per year |
284 | |||
| 24 |
LexisNexis Canadalexisnexis.com
Leading global provider of information and technology solutions for legal, corporate, tax, and government professionals, focusing on innovation, comprehensive content, and workflow efficiency |
225 | |||
| 25 |
Green and Spiegelgands.com
A boutique immigration law firm with offices in multiple locations, specializing in all categories of North American immigration law for over 40 years |
222 | |||
| 26 |
Gardiner Roberts LLPgrllp.com
Established in the 1920s, we are a mid-sized law firm serving diverse clients including banks, municipalities, tech companies, and real estate developers |
213 | |||
| 27 |
Harrison Pensa LLPharrisonpensa.com
A full-service law firm based in London, Ontario, specializing in litigation, business law, real estate, family, wills and estates, and personal injury law |
181 | |||
| 28 |
Fraser Milner Casgrain LLPdentons.com
A global law firm formed by the merger of Salans LLP, Fraser Milner Casgrain LLP, and SNR Denton, focused on providing clients a competitive edge worldwide |
181 | |||
| 29 |
Chodola Reynolds Bindercrblaw.ca
A law firm in Windsor, Canada since 1973, specializing in civil litigation, insurance defense, real estate, and corporate law with a reputation for excellence and integrity |
7 | |||
| 30 |
CiteRightciteright.net
AI-powered Knowledge Management tool for lawyers, automating citations and document drafting to save time and reduce errors in litigation workflows |
4 | |||
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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.
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The same list elsewhere in Canada
The same list elsewhere
- Law firms in the world 3,223