LAWYER PROFILE
John Mastoras

John Mastoras

Canada 2026

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Ranked in 1 practice area

About

Provided by Norton Rose Fulbright

Canada

Practice Areas

John Mastoras is a senior partner in our Canadian employment and labour law group, and acts exclusively for employers. He is known to clients as a passionate and dedicated labour lawyer. He regularly litigates and provides strategic advice in connection with labour arbitrations, labour relations board disputes, collective bargaining negotiations, human rights proceedings, occupational health and safety charges, workplace insurance, labour injunctions and common law employment actions. His practice spans union and non-union workplaces for both federally and provincially regulated employers.

John is often chief spokesperson in collective bargaining and provides helpful counsel in this regard to a variety of employers. He also routinely acts for a number of employer associations and provides innovative and practical advice to the associations and their members.

John is frequently called upon to litigate highly contentious matters such as disruptive labour disputes and workplace mental health issues in various industries, including energy, pulp and paper, pharmaceutical, health care, insurance, long-shoring, retail, food processing, transportation, steel, building services, technology, automotive and manufacturing more generally.

Chambers Review

Provided by Chambers

Chambers Canada Guide

Employment & Labour - Ontario

Band 2
Band 2

Individual Editorial

John Mastoras is a highly regarded lawyer based in Toronto, who is particularly experienced in contentious labour and employment matters, including both litigation and arbitration. He is also skilled in collective bargaining negotiations.

Strengths

Provided by Chambers

  • John's client-focused approach makes him the preferred employment lawyer of choice for many. Simply stated, he is a master of his craft.

    Employment & LabourChambers Canada Guide
  • John has been exceptional for us, he is a superb counsel.

    Employment & LabourChambers Canada Guide
  • John is amazing.

    Employment & LabourChambers Canada Guide

Ranked Individuals at Norton Rose Fulbright (120)

Alberta

British Columbia

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