Understanding Ontario Rent Increase Rules is important for both landlords and tenants. Imagine receiving a rent increase notice and not knowing whether it follows the law. It can be stressful. Knowing the basic rules helps everyone make better decisions. In Ontario, most rent increases require at least 12 months since the tenancy began or the last increase. Landlords generally must also provide written notice at least 90 days before the increase takes effect. For 2026, the rent increase guideline is 2.1% for most rent-controlled units. However, some newer rental units may be exempt, and certain increases above the guideline require approval. Tenants should check their notice carefully and understand their rights. Landlords need to follow the proper process and use the correct forms. A little knowledge can prevent confusion and rental disputes. For more information about Ontario Rent Increase Rules, review official Ontario government guidance before taking action.