Reminder: Canada's Bill C-58 set to take effect

The legislation received royal assent in June 2024, shortly after it passed through the Senate.

Ban on replacement workers use

Bill C-58 has two main components.

First, the bill repeals the limited prohibition on replacement workers under Part I of the Canada Labour Code.

The legislation states, among others, that:

• Employers will be banned from using several types of individuals to do the work of striking or locked-out workers. This includes any employee or manager hired after the employer or union gives notice to bargain.
• For employees hired before notice to bargain, employers may only use employees if they normally worked at the location where the strike or lockout is taking place prior to the notice to bargain.
• Employers will be prohibited from using contractors to perform union work during a strike or lockout, regardless of when they were hired.
• Employers may not use volunteers, students, or members of the public to perform union work during a strike or lockout.
• Employers will be prohibited from allowing employees in a bargaining unit to “cross the picket line” and work if the bargaining unit is involved in a full strike or lockout where all employees are expected to stop working.

Employers will only be allowed to use replacement workers in “exceptional circumstances”, including: 

• to prevent threats to life, health or safety of the public;
• to prevent destruction of, or serious damage to, the employer’s property or premises; or
• to prevent serious environmental damage affecting the employer’s property or premises. 

"In these circumstances, employers will be required to offer bargaining unit members the opportunity to do the necessary work before using replacement workers," said the federal government.

Unions that believe an employer is illegally using these workers can file a complaint with the Canada Industrial Relations Board (CIRB), which will investigate the matter. If prosecuted and convicted, an employer could face a fine of up to $100,000 per day.

Maintenance of activities process

Bill C-58 also amends the maintenance of activities process under Part I of the Code as follows:

• Parties will be required to enter into an agreement no later than 15 days after notice to bargain has been given and must immediately file their agreement with the CIRB and the Minister of Labour. This condition applies even if the parties agree that no activities need to be maintained.
• If the parties do not reach an agreement within 15 days, they will be required to apply to the CIRB to determine which activities need to be maintained, if any.
• The CIRB must resolve these matters within 82 days and will have the authority to expedite proceedings. The Minister will continue to have the authority to refer questions to the CIRB about whether an agreement sufficiently prevents an immediate and serious danger to public safety or health.
• Employers and unions will be required to have a maintenance of activities agreement in place before issuing 72 hours’ notice for a strike or lockout.

Richard Charney, senior partner at Norton Rose Fulbright, previously told Human Resources Director that employers should not define any essential work too broadly in the agreements to reduce the impact of strikes. That could lead to union disputes and arbitration taking control, which takes negotiations out of the employer’s hands. The best way to deal with the legislation is to maintain good relations with trade unions, he said.

“Replacement worker bans represent a shift in bargaining power away from employers and toward unions in the collective bargaining process,” said Herb Isherwood, partner and Canadian national chair for employment and labour at law firm Norton Rose Fulbright Canada.

"Should bargaining reach an impasse, a work stoppage represents not just a potential reduction in work, but potentially a total cessation of bargaining unit work. Any further expansion of replacement worker bans would be a significant development for employers."

Several Canadian provinces have introduced their own anti-scab legislation.

However, Isherwood also noted that since the June 2024 adoption of Bill C-58, there have been two further expansions of replacement worker bans in Canada.

He explained that in August 2024, a British Columbia court held that the province’s replacement worker ban could have extraterritorial effect to prevent an employer from relocating bargaining unit work from a BC location to a location outside the province. This decision is currently under appeal.

"As of June 20, 2025, there will be four Canadian jurisdictions with replacement worker bans in place, and potentially an expansive interpretation of the territorial reach of those bans," said Isherwood. "Further developments in this area should be of significant interest to employers with unionized workforces throughout Canada."