Can a probationary employee sue for wrongful dismissal in Ontario?

Yes. Probationary employees can sue for wrongful dismissal, though the practical entitlement during a genuine probationary period is often much smaller than for an established employee, since courts generally recognize that employers are entitled to assess suitability during a reasonable initial period and dismiss with relatively little notice if the employee simply is not working out, provided the employer acts in good faith and gives the employee a genuine chance to demonstrate suitability for the role.

The Employment Standards Act's minimum notice requirements typically only apply after an employee has completed a minimum period of continuous employment, so very early terminations may fall entirely outside statutory notice obligations, though common law considerations can still apply to some probationary dismissals depending on the circumstances. A probationary dismissal made in bad faith, or one that misrepresents the true reason for ending the employment, can still expose an employer to a considerably larger claim than a straightforward, good-faith decision that the employee was not suited to the role.