Does an Ontario employer have to pay employees for time spent in mandatory training?

Generally, yes. Under the Employment Standards Act, 2000, time an employee spends in training that the employer requires them to attend is generally treated as hours of work, and needs to be paid at least at the employee's regular rate, including counting toward the weekly hours that could trigger overtime. This applies whether the training happens on-site, at an off-site location the employer arranges, or online, as long as attendance is mandatory rather than genuinely optional.

A common misconception is that training doesn't count as "real work" because the employee isn't performing their usual job duties during it, or that unpaid training is fine as long as it's framed as onboarding, orientation, or professional development. Neither framing changes the underlying analysis under the ESA — if attendance is required, the time generally has to be paid like any other hours of work.

Genuinely voluntary training that an employee chooses to attend, with no requirement or expectation from the employer that they do so, is treated differently and may not need to be paid, but employers should be careful about training that's technically "optional" while practically expected. If your business runs mandatory training sessions, make sure payroll actually reflects that time.