John M. Campbell
Counsel
- Year of Call, Ontario (1983)
Areas of focus

Areas of focus
John Campbell is counsel in Gowling WLG's Toronto office and a member of the firm's National Tax Group. With over 40 years of experience, John advises clients on a broad range of domestic and international income tax matters, focusing on corporate reorganizations, mergers and acquisitions, international tax planning, and business transactions.
John is known for crafting strategic, practical tax solutions that help businesses navigate complex regulations while achieving their financial goals. He actively works across industries to design tailored tax strategies that drive compliance and enhance financial outcomes.
In addition to his transactional work, John represents clients in disputes with federal and provincial tax authorities. He has successfully appeared before the Tax Court of Canada, the Federal Court of Appeal, and Ontario courts, resolving reassessments, notices of objection, and other tax disputes.
John regularly writes and speaks on key developments in tax law. He has lectured for the Canadian Tax Foundation and the Law Society of Ontario, sharing his extensive knowledge with fellow professionals.
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