From our payroll expert, Alan McEwan:
The gist of it is that there is not a single definition of ‘province’ in payroll.
For source deduction and reporting purposes, if employees work remotely, the province of employment will likely be where the employer payroll is processed. There are some exceptions, but they mostly apply to sales staff.
For the purpose of the laws that apply to employment, such as employment standards, worker’s compensation, human rights, etc., the province that applies is where employees physically work.
This means that an ON employee who works remotely for an employer located in BC, would consider the person as having BC as the province of employment, but the statutory holidays that would apply are those based in ON.
Again, there are exceptions, but these apply to employers who are federally regulated, where the Canada Labour Code applies. The other exception is for the rules around pensions, where both the physical province and the federal government share jurisdiction.
****
Hope that helps. Glenn