In the case of your remote workers who occasionally report to the office in Calgary, Alberta, there are a few key considerations:

1. Taxation: As you mentioned, employees are generally taxed based on the location where they perform their work. If your remote workers are physically located in different provinces, they may be subject to the tax regulations of those provinces. This means you may need to withhold and remit provincial income taxes based on each employee’s respective location.
2. Provincial Employment Legislation: Employment legislation typically applies based on the jurisdiction where the employee is physically working. In the case of your remote workers, they would likely be subject to the employment legislation of the province where they are physically located while working remotely. For example, if an employee lives in British Columbia and primarily works remotely from there, they would generally fall under British Columbia’s employment legislation.
3. Potential Exceptions: There may be exceptions or special circumstances that could affect the application of employment legislation. For example, if an employee’s work primarily revolves around the office in Calgary, Alberta, even though they work remotely most of the time, there may be an argument that Alberta employment legislation applies. This is where consulting an employment lawyer or payroll expert is crucial to assess the specific details of each employee’s situation.

 
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Hiring Remote Workers In Other Provinces? Legal Considerations For Employers
Remote Work From Other Jurisdictions: What Employers Need To Know
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