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The ability to simplify ever more complex rules and regulations into clear, actionable advice has become a defining characteristic of the country’s top tax law firms.
With new tax rules impacting a wide array of clients – from the 2024 amendments to the general anti-avoidance rule (GAAR) and mandatory disclosure requirements to updates on alternative minimum tax and transfer pricing – the demand for clarity has never been greater.
Two legal experts share this perspective and underscore that effective communication is crucial in successfully guiding clients through an increasingly intricate web of domestic and international tax laws.
“Simplicity is key, and it’s quite difficult with just the large amount of new tax laws that are coming in different jurisdictions, let alone in Canada,” says Shaira Nanji, a tax law partner at KPMG Law LLP, Canada.
Similarly, Byron Beswick, partner and national leader of corporate reorganizations and divestitures at KPMG Law, Canada, asserts that top-tier firms serve as trusted interpreters for their clients.
“Transactions are often multi-jurisdictional, so you really need that subject matter expertise, even within tax law, as there’s a lot of different areas to be a specialist in,” he says.
Thomson Reuters’ Law Firm Financial Index (LFFI) report for the second quarter of 2024 highlights the legal profession's resilience and adaptability, traits exemplified by the top tax law firms as they steer through complex regulations and deliver straightforward, results-oriented client advice.
Across the board, the 10 top tax law firms recognized in Canadian Lawyer’s sixth edition excelled in delivering tailored client solutions, staying ahead of complex regulatory changes, and raising the bar for legal excellence and expertise.
Their strategies and vision align with the insights of the industry’s leading minds, who stress that to succeed, tax law firms should focus on the following:
strategic partnerships
niche specialization
selective technology adoption
prioritizing firm culture
“One of the advantages of a boutique firm can be having control over their culture, ensuring that they have and are protective of a culture that people just enjoy working within,” says Beswick.
Nanji adds, “I think the key to success would be having to focus on something a bit more niche. The breadth of services is much more difficult to provide.”
Confronted with the dual challenge of increasingly sophisticated international tax rules and ever-escalating domestic compliance demands, CL’s winning tax law firms have set themselves apart by leveraging deep knowledge and expertise to bridge the gap between legal intricacies and clients’ practical needs.
One such example is Canada’s Digital Services Tax (DST), which imposes a three percent tax on multinational digital firms with Canadian revenues exceeding $20 million.
Enacted in 2024, the DST applies retroactively to revenues earned since January 2022, presenting compliance and operational obstacles for affected businesses. The firms on this year’s list are at the forefront of helping clients manage these changes while anticipating their long-term impact.
According to the legal experts, other challenges include:
Global tax alignment: driven by the OECD BEPS initiatives, introducing new international tax rules, including interest deductibility, minimum tax, and transfer pricing regulations
Complex domestic laws: new legislation affecting small businesses, making compliance and understanding more challenging
Overall complexity: taxpayers face significant difficulties in understanding, managing, and complying with the increasing volume of complex legislation
“So, just from every direction, it seems we’re getting new, complex legislation without – it seems to us – a lot of thought put into how taxpayers are going to deal with this legislation, how they’re going to manage it, the cost, the complexity, and even knowing what to do,” says Beswick.
Nanji notes, “In addition to that, I’d say some of the recent domestic changes that have been very challenging for Canadians to navigate include the bare trust reporting requirements, capital gains, and the overall increase in reporting and compliance obligations tied to transaction notifications.”
For the 2025–26 Top Tax Law Boutiques list, CL’s team conducted a nationwide survey of lawyers, in-house counsel, and clients. To qualify, firms needed to focus primarily on tax law. The final rankings were based on a points system that considered votes received, insights from the Lexpert peer survey, where applicable, and feedback from senior members of the bar.
This year’s prestigious list highlights the legal leaders, but the results also shed light on the benefits of boutique firms and the challenges they face, according to the experts:
Advantages: flexible and adaptable in forming networks; can develop alignments with independent firms in other jurisdictions
Challenges: without pre-established networks, it can be difficult to provide holistic advice, especially when dealing with complex, multi-jurisdictional matters; transaction speed often requires anticipating jurisdictional needs and having connections at the ready
“Boutique firms have the ability to shift focus and shift the people they work with fairly quickly,” says Beswick. “I think a critical thing for boutiques to do is to have that network of professionals domestically around the world, that they can rely on for what they need. It takes time to develop those relationships and to find the right people.”
From Nanji’s experience, she remarks, “As long as boutique firms, to the extent that they can, create and establish those relationships in different jurisdictions, that would be most helpful. I really appreciate the member firms, coming from a firm that has such a wide reach globally.”
CL’s survey data shows that respondents choose to work with tax law boutiques for various reasons:
38.5 percent cite tax law knowledge, skill, and specialization, ensuring clients receive the right and best advice the first time around
15.4 percent say opportunities abound for mentorship and hands-on experience with tax law
9.6 percent believe they receive better client service, more in-depth knowledge, better value and rates; the same percentage report the feeling of being part of a family versus just a number in a small-firm culture
7.7 percent point to a boutique firm’s independence and ability to provide tailored tax advice unhindered by internal firm politics
The Top Tax Law Boutiques survey spotlights the exceptional expertise and dedication shaping Canada’s tax law space. While all the winners’ outstanding reputations have earned the trust of their clients and referral partners, four standout firms profiled here are pushing boundaries and setting benchmarks for excellence, affirming the collective achievement of the entire Top 10 list.
With a specialization in high-stakes, complex tax litigation, the five-time winner of the top tax law firm distinction stands out for its singular focus on helping clients overturn Canada Revenue Agency (CRA) assessments.
Counter Tax Litigators LLP's mission is deeply rooted in protecting the economic value mature companies and wealthy families have built.
“Our competitive advantage comes from our people’s expertise and applying that expertise within the framework we’ve created to deliver superior tax results,” says tax litigation partner Natalie Worsfold. “That structured discipline and accountability are the DNA of our firm’s culture.”
Several strategies have contributed to Counter Tax Litigators’ repeated recognition:
Client ROI: Last year, the firm achieved a 24:1 return on client investment, reflecting its ability to resolve disputes effectively while protecting economic value.
Unparalleled expertise: As recognized leaders in tax controversy, the firm’s lawyers are trusted for their insights and proven success in high-stakes disputes.
Integrated tax litigation framework: Unique to Counter Tax Litigators, its structured yet flexible framework combines case-specific strategies with the highest-quality legal analysis and advocacy. This approach sets clear targets, measures performance, and benchmarks success, delivering results unmatched in the industry.
Custom reporting suite: Clients receive tailored insights, dynamic progress updates, and risk assessments that promote transparency and strategic decision-making.
Counter Tax Litigators also leverages custom reporting software and third-party AI tools to enhance its practice, particularly in risk quantification and communication.
“Part of what we’ve done in our custom reporting suite is transforming our legal analysis and recommendations into clear, actionable insights CEOs and decision-makers can use to navigate their tax disputes,” Worsfold adds.
Survey respondents praised the firm for its deep expertise in tax law and strategic approach to litigation, ensuring every client receives focused, effective legal representation tailored to their unique circumstances.
Notable client comments include:
“Knowledgeable and innovative.”
“Systematized approach is great for small and medium-sized businesses with sophisticated internal teams.”
“Has a good reputation for quality work and profile in the marketplace.”
Worsfold attributes the firm’s success to maintaining the highest standards for every case, comparing their approach to ISO standards but for litigation. The firm’s ISO-like standards and framework position its legal team to deliver superior client results.
“CRA audits are more aggressive and adversarial, with pressure to generate tax revenue,” Worsfold says. “Two-thirds of the tax court’s caseload is now general procedure claims, reflecting higher stakes and complexity.”
The team’s collective expertise is another key to their success. For example, Peter Aprile, senior counsel in tax litigation, was recently recognized as a tax practice leader in the International Tax Review (ITR).
In addition to its legal work, the firm develops tools to keep clients informed and prepared throughout lengthy tax disputes. One such tool designed to help clients navigate examinations for discovery earned the top tax law firm an Innovator of the Year nomination from the ITR.
“You need to be ready financially, emotionally, and strategically,” Worsfold explains. “We’ve created these reports to help clients understand their risks, chances of success, and what the process will look like.”
Beyond its day-to-day work, Counter Tax Litigators is committed to creating broader change within the tax system. Through its “1% for Good” program, the firm dedicates one percent of its revenue to initiatives addressing systemic issues.
“There are so many things I’d love to fix,” Worsfold says. “It’s about delivering the best results for clients and helping prevent future issues.”
The five-time victor has built its reputation as a trusted tax law boutique by working closely with owner-managed businesses, small and medium enterprises, and entrepreneurs across various industries such as real estate and manufacturing.
Co-founder and partner Robert Kepes attributes much of the firm’s success to its deep understanding of its clients’ needs.
“We’ve been working together for over two decades, and our team’s background aligns with the needs of our clients,” he says. “We understand the entrepreneurial mindset because we’ve lived it ourselves.”
Survey respondents praised the firm, noting:
“Exceptional experience with high-net-worth clients.”
“They get the job done.”
“Lawyers are very experienced and knowledgeable, with good success rates.”
Referrals are the lifeblood of this top tax law firm’s practice, thanks to its laser focus on tax law that spans tax planning and litigation.
“Referring law firms know we won’t poach their clients’ other legal work, such as real estate or family law, and that makes us a safe option for referrals,” Kepes says. “We’ve also developed expertise in cross-border work, helping clients moving to Canada.”
The top tax law firm prides itself on client service and delivering results, along with:
a strong support team that keeps its operations running smoothly
legal leaders’ decades of combined expertise and experience
entrepreneurial spirit and willingness to take risks
maintaining strong relationships with referral sources
The ever-changing tax space keeps the firm’s lawyers on their toes, and Kepes is quick to point out the pressures this creates for firms and their clients.
“In recent years, the government has introduced more regulations to reduce what they perceive as aggressive tax planning,” he explains. “Rules such as reportable and notifiable transactions require significant reporting, and the bar for what triggers these requirements keeps getting lower. For example, you used to need two out of three hallmarks to report; now it’s just one.”
Kepes also raised concerns about what he calls a troubling trend around the government’s encroachment on solicitor-client privilege in tax matters.
“The government seems to treat it as more of a guideline in tax matters, even though the courts have consistently upheld it,” he reflects. “Lawyers are now fighting against reporting requirements that could force us to disclose client identities, which breaches privilege. These challenges keep us vigilant.”
As tax law changes with every government budget, the team embraces continuous learning to maintain its competitive edge and stay ahead. In fact, teamwork is a cornerstone of its collaborative practice. The firm also harnesses technology to improve efficiency and streamline research. Tools such as AI-driven research platforms have become valuable additions to its toolbox.
“These tools are invaluable for experienced lawyers; they help us ask better questions and find answers faster,” Kepes says while acknowledging the tech’s limitations. “You need the knowledge to know whether the answers you’re getting are right. These tools can’t replace human expertise.”
The constant evolution of tax law isn’t a drawback for the legal team. Instead, they view it as an opportunity.
“We enjoy the challenge,” Kepes says. “Every budget and every new rule keep us sharp and add value for our clients.”
In just its second year since rebranding, Beitel Tax Law has already earned a spot among Canada’s top tax law firms. This first-time recognition highlights the firm’s rapid rise and distinctive approach in a competitive field.
“What makes our culture different is that we have very small egos and a strong desire to collaborate,” managing director Jeremie Beitel says. “It’s about working together as a full team rather than competing internally or being siloed.”
The top tax law firm’s commitment to fostering a people-centred culture extends to its overall client service approach.
“We recruit for emotional skills, especially humility,” Beitel explains. “We want our clients to benefit from the combined knowledge of the whole team, not just the lawyer assigned to the file. That only works if we check our egos and collaborate.”
One of the firm’s standout strategies has significantly impacted client satisfaction: intentionally setting lower billable targets for its lawyers.
“This choice means that when clients need us, we’re available,” he remarks. “If lawyers are constantly at capacity, they don’t have time for emerging issues. Starting with a manageable workload ensures we can address client needs immediately.”
That approach has paid off.
Survey respondents praised the firm’s responsiveness, technical expertise, and exceptional service:
“Great work led by a trusted and educated team.”
“They are very technical and always on the spot with their analysis and deliverables.”
“Excellent and responsive service. Very knowledgeable and trustworthy advice.”
The top tax law boutique works almost exclusively with small businesses and entrepreneurs, where tailored guidance is critical. However, Beitel sees challenges for small businesses in the current tax landscape.
“The biggest trend is the deterioration of the tax dispute resolution process for small businesses,” he explains. “Many taxpayers are moving through the system without proper advice while the system struggles with demand. For our clients, we deal with those challenges by focusing on efficient, practical solutions while also focusing on training the next generation of tax lawyers to meet the growing need.”
Despite being a young firm, Beitel Tax Law is growing quickly but carefully. It now has 14 lawyers and one articling student and will welcome three students in 2025.
“We’re trying to grow sustainably,” Beitel reflects. “We’ve added some talented senior lawyers this year and are trying to find the right students so we can grow on both ends without diluting our talent pool.”
The firm also boasts unique accomplishments. Beitel and fellow lawyer Brian Nichols have published work cited by the Supreme Court of Canada in tax cases.
“This speaks to how we think not only about the current file but about the progress of the system as a whole,” he adds.
The 70-plus-lawyer tax law boutique has been named among Canada’s best in every edition since the prestigious list’s inception in 2015.
From two offices in Vancouver and Toronto, Thorsteinssons has built an unmatched reputation for its depth of expertise, collaborative culture, and innovative approach to navigating the complexities of Canadian tax law.
“Tax is all we do, and that focus has served us well for over 60 years,” managing partner Jim Murdoch says. “Our boutique model has been key to our success, and because we focus solely on tax, that minimizes conflicts. Most of the time, our only adverse party is the Canada Revenue Agency, so we can act for clients without the conflicts that often arise in full-service firms.”
The firm has consistently excelled across multiple areas, earning recognition for its:
comprehensive tax expertise
strong referral relationships
client-centred approach
dedication to talent recruitment
Thorsteinssons’ emphasis on tax law covers everything from planning and private client work to corporate tax, commodities and customs, dispute resolution, and litigation. This breadth allows the firm to serve as a one-stop shop for tax matters while maintaining a personal touch in client service.
It’s an approach that has enabled the top tax law firm to build strong relationships with other professionals in the legal and accounting fields based on its commitment to service excellence.
Survey respondents highlighted the firm’s exceptional qualities:
“They are the leading tax law firm in Canada, with leading practitioners in planning and litigation.”
“Substantial bench strength in tax advising and litigation. Far and away the largest and most successful tax boutique.”
“Deep experience with experts in niche areas across a variety of specialties; responsive and well-staffed.”
Murdoch believes the main challenge in Canada’s tax law space is the sheer volume of legislative changes. He notes that tax law evolves constantly, multiple times per year, and the changes are often highly complex and unclear.
“We’re also seeing more disputes, partly due to this uncertainty,” he says. “The CRA is very active and aggressive in audits, placing heavy burdens on taxpayers. It’s a different agency than when I started my practice over 20 years ago.”
Despite these challenges, the firm remains focused on staying ahead as the team works diligently to track every development to give clients the most accurate advice possible. Its legal leaders are also keeping an eye on AI developments and are beginning to explore its applications. But for now, it’s a productivity tool like other technologies it has adopted.
More importantly, remaining at the forefront in a competitive environment starts with investment in its people, Murdoch asserts. Over the past year, the top tax law firm has ramped up efforts to recruit and train top-tier talent and the next generation of tax lawyers.
“We’ve had success bringing in great talent, and we’re devoting more resources to this,” he says.
Canadian Lawyer’s sixth bi-annual Top Tax Law Boutiques survey asked lawyers, in-house counsel, and clients across the country to select tax law boutiques firms that represented the best in class in 2025.
To be considered in the vote, firms were required to have the majority of their business come from tax law work. The final rankings were determined through a points system in which firms were rewarded on a sliding scale for the number of votes by ranking. The quantitative results were combined with the Lexpert peer survey results, where applicable, along with feedback from respected senior members of the bar.