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List of law firms in Ontario

Tamtam tracks 30 law firms headquartered in Ontario. This list ranks all of them by number of employees on LinkedIn, led by KPMG Canada, Fasken and Borden Ladner Gervais LLP (BLG). Their median headcount is 807. Half of them were founded in 1920 or later. The most common headquarters are Toronto (25), London (2) and Ottawa (2).

🇨🇦 Ontario30 companiesUpdated Nov 12, 2026

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.

#CompanyIndustryHeadquarters EmployeesFounded
1
KPMG Canadakpmg.com

Providing audit, tax, and advisory services to public, private, nonprofit, and public sector organizations across Canada with professionalism.

Financial Services 🇨🇦 Toronto 10,017 n/a
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

Law Practice 🇨🇦 Toronto 2,458 n/a
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

Law Practice 🇨🇦 Toronto 2,290 1823
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

Law Practice 🇨🇦 Toronto 2,088 1855
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

Law Practice 🇨🇦 Toronto 1,707 1862
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

Law Practice 🇨🇦 Toronto 1,686 1856
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

Law Practice 🇨🇦 Toronto 1,572 n/a
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

Law Practice 🇨🇦 Toronto 1,564 1952
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

Law Practice 🇨🇦 Toronto 1,415 1957
10
Torys LLPtorys.com

Providing superior counsel and client service, our cross-border team offers innovative solutions for clients' toughest problems with regional expertise

Law Practice 🇨🇦 Toronto 1,106 1941
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

Law Practice 🇨🇦 Toronto 1,063 n/a
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

Software Development 🇨🇦 Toronto 945 n/a
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

Law Practice 🇨🇦 Toronto 935 1903
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

Law Practice 🇨🇦 Toronto 874 1888
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

Law Practice 🇨🇦 Toronto 807 n/a

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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

Law Practice 🇨🇦 Toronto 788 1797
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

Law Practice 🇨🇦 Toronto 643 1919
18
Goodmans LLPgoodmans.ca

A leading Canadian law firm with expertise in business law, litigation, public/private sectors, providing innovative solutions for clients' success

Law Practice 🇨🇦 Toronto 520 n/a
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

Law Practice 🇨🇦 Ottawa 505 1890
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

Hospitals and Health Care 🇨🇦 Ottawa 481 1901
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

Law Practice 🇨🇦 London 464 1929
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

Law Practice 🇨🇦 Toronto 327 1954
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

Government Administration 🇨🇦 Toronto 284 2019
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

IT Services and IT Consulting 🇨🇦 Toronto 225 n/a
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

Legal Services 🇨🇦 Toronto 222 1962
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

Law Practice 🇨🇦 Toronto 213 1920
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

Law Practice 🇨🇦 London 181 1999
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

Law Practice 🇨🇦 Toronto 181 1839
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

Law Practice 🇨🇦 Windsor 7 1973
30
CiteRightciteright.net

AI-powered Knowledge Management tool for lawyers, automating citations and document drafting to save time and reduce errors in litigation workflows

Legal Services 🇨🇦 Toronto 4 2017

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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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