What a valid N9 needs
For a month-to-month tenancy, or a fixed term ending on the date the tenant wants to leave, the N9 must give at least 60 days of notice, and the termination date must be the last day of a rental period. For a tenancy that still has time left on a fixed term, the earliest termination date is the last day of that term, even if 60 days would come sooner.
The notice has to be in writing. The LTB form is the safe way, but a letter or email that clearly says the tenant is ending the tenancy on a specific date is generally treated the same way. A text that says "we're thinking of moving in the fall" is not notice.
This is general information, not legal advice. The rules come from Ontario's Residential Tenancies Act and the Landlord and Tenant Board (LTB). For the current forms and guidance see tribunalsontario.ca/ltb, and speak to a lawyer or paralegal about your own situation.
Rental period, not calendar month
If rent is due on the 1st, the rental period is the calendar month and the termination date is the last day of a month. For example, an N9 received on September 20, 2026 counts 60 days to November 19; the last day of that period is November 30, 2026, which is the earliest valid date.
If the tenancy started on the 15th and rent is due on the 15th, the periods run from the 15th to the 14th. The same September 20 notice counts to November 19, and the period that contains November 19 ends on December 14, 2026. A tenant who writes November 30 on that notice has picked a date that is not the end of a period, and the notice ends nothing.
Check the date against your own lease before you accept it. A polite reply saying "the earliest date that works for this tenancy is December 14; do you want to correct the notice?" saves a much worse conversation in December.
What you can and cannot do in the notice period
Once notice is given, you can show the unit to prospective tenants after making a reasonable effort to tell the tenant, during daytime hours; check the RTA's entry rules for the exact terms. The tenant still pays rent to the end of the notice period, and the rent deposit is applied to the last month, so the tenant's final rent payment is usually the second-last month.
What you cannot do is treat the notice as permission to enter whenever you like, to change the locks early, or to charge for "breaking the lease" when the notice is valid. If the tenant wants to leave earlier than a valid date allows, the options are an agreement to end the tenancy (the N11, signed by both of you) or an assignment to a new tenant. You do not have to agree, but you cannot unreasonably refuse an assignment.
If the tenant leaves without valid notice
If a tenant moves out on a date that was not valid, the tenancy has not ended on paper. In practice, once the unit is empty and the keys are back, you are usually better off re-letting immediately than pursuing the shortfall, because you have a duty to try to re-let and every week the unit sits empty is money you may not recover. Keep the record straight (the notice you received, the date the keys came back, the date you re-let) in case it goes to the LTB.
Re-letting: the notice period is your head start
Sixty days is enough time to have the next tenant signed before the current one leaves, if you start on day one. Post the listing within the first week, show the unit in the second and third, screen and sign in the fourth, and move the new tenant in on the first day of the next period. The guide on a rental sitting empty walks through the posting, showing and screening steps in order.
How KeyToRental records the notice and turns the unit
When a tenant gives notice, you record it on the lease and KeyToRental checks the date against the tenancy: it works out the earliest valid termination date from the rent due day and the fixed term, and warns you if the date the tenant wrote is earlier than that. The move-out date goes on the lease, the last month's rent shows as covered by the deposit, and the unit is flagged as coming available. From there the Post Kit writes the listing, the AI phone line answers enquiries, viewings are self-booked and the screening application and e-signed lease follow.