In plain English
Rent can be increased no more than once every 12 months for the same tenant.
The statute text
119 (1) A landlord who is lawfully entitled to increase the rent charged to a tenant for a rental unit may do so only if at least 12 months have elapsed,
(a) since the day of the last rent increase for that tenant in that rental unit, if there has been a previous increase; or
(b) since the day the rental unit was first rented to that tenant, if clause (a) does not apply.
(2) An increase in rent under section 123 shall be deemed not to be an increase in rent for the purposes of this section.
Guideline
View this section on the official Ontario e-Laws site →
Reproduced under the King’s Printer for Ontario / Open Government Licence – Ontario. Confirm against the official e-Laws consolidation before relying on it.