Like most answers from lawyers, it depends.
If the employer had valid “cause” to terminate your employment, then the employer does not owe you anything. If you are terminated “without cause”, then the employer is required to give you notice of your termination, or pay in lieu of. Most people have heard of the Employment Standards Act (ESA), but it’s important to recognize that this is minimum legislation. For some employees, the difference between ESA entitlement versus common law entitlement can be as much as 2 year’s salary!
If you’re an employee facing termination, or an employer considering the termination an employee, it’s best to speak with an employment lawyer before doing anything. Getting the right advice today will help avoid disputes tomorrow.