Labour Relations - Replacement Workers
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The employer’s duties and obligations regarding the use of replacement workers during a legal strike or lockout will change as of June 20, 2025. The new provisions of the Canada Labour Code (the Code) and the related Rules of Procedure apply in respect of any strike or lockout that is ongoing on June 20, 2025, or after.
What is a replacement worker complaint?
A replacement worker complaint is a formal request asking the Canada Industrial Relations Board (the Board) to determine whether an employer has used individuals to perform work normally done by employees who are on strike or locked out, in violation of sections 94(4) to 94(8) of the Code.
Who can file a replacement worker complaint?
Only the following parties can file a replacement worker complaint:
- An individual worker who is part of the bargaining unit involved in the work stoppage; or
- A representative of the bargaining agent (the union) for that unit.
What is considered “replacement work”?
Replacement work is work that is usually performed by someone who is on strike or locked out and that is being done by:
- a person hired after notice to bargain was given;
- a contractor or employee of another employer;
- a transferred employee from another worksite; or
- a volunteer, student or member of the public.
Exceptions may apply under certain conditions, such as when there are threats to safety, existing contractor services or maintenance of activities agreements.
How do I file a replacement worker complaint?
To file a replacement worker complaint, you must:
- read the Rules of Procedure on Replacement Worker Complaints;
- complete the Replacement Worker Complaint Form;
- gather and submit relevant supporting documents (such as a collective agreement, a notice to bargain, a list of replacement workers, etc.);
- file the complaint through the Board’s E-Filing Web Portal or deliver it to the Board’s Ottawa office; and
- send a copy of the complaint and all documents to the employer and any interested parties at the same time.
What is the filing date of a complaint?
In most cases, the filing date of a complaint is the date the Board receives it. However, if the complaint is sent by registered mail, the filing date is the date the complaint is mailed to the Board.
What if I do not have all the required documents when filing?
You must provide an explanation for any missing documents when filing your complaint. Not doing so could delay the process or result in your complaint being dismissed.
What happens after the Board receives the complaint?
Upon receiving the complaint, the Board sends a notice of complaint to all parties, assigns an industrial relations officer (officer) and sets a submission schedule and a case management conference (CMC) date.
The employer must respond within two days, and the complainant must reply two days after that.
What is the role of the Board’s officer?
The Board’s officer:
- coordinates the processing of the file;
- facilitates communication between the parties;
- may request additional documents or make recommendations; and
- works to help parties reach a resolution.
What documents must the employer provide?
The employer must send the Board:
- lists of current workers and contractors;
- job titles and classifications;
- contracts and timesheets (for contractors);
- shift schedules and organizational charts; and
- a business description.
Can the timelines be extended?
Timelines can only be extended in exceptional circumstances. The Board prioritizes quick resolution of these complaints due to their impact on collective bargaining and labour relations.
How can I send documents to the other parties?
If you file documents with the Board as part of a case, you must immediately send a copy of those documents to all the other parties involved. You can send your documents to the other parties by email, courier, Dropbox, USB key, etc. You also need to tell the Board when and how you sent them.
What is a CMC?
A CMC is a virtual meeting with the parties where the Board may:
- discuss the complaint;
- confirm timelines;
- explore possible settlements;
- identify any additional interested parties; and
- address any procedural issues.
Will there be an investigation?
An investigation can happen. The Board may:
- appoint an officer to investigate;
- allow the officer to enter the worksite, review records and contact employees; and
- share the investigation report with the parties and request written comments.
How does the Board make a decision?
After reviewing all the evidence, the Board may:
- order the employer to stop using replacement workers;
- make any other order it considers reasonable to meet the objectives of the Code; or
- dismiss the complaint.
Where can I get help or more information?
For information on how to contact the Board, please see the Contact Us page.