Ontario 2025 Rent Increase Regulations. It's a rate that's the lowest in the country, below the average inflation rate of 3.1 per cent. This is called the rent increase guideline or the guideline.

For the most part, landlords can increase rent in the following scenarios: Housing rules in ontario require landlords who want to increase rent to offer 90 days’ written notice to tenants — rent cannot be raised more often than once per year.