At the start of a tenancy, the rent is set at whatever amount the tenant and landlord agree to as part of the tenancy agreement. From that point on, the landlord can only raise the rent once every 12 months (but not in the first year of the tenancy) by a percentage equal to inflation. This allowable rent increase percentage changes each year, so visit TRAC’s webpage, Rent Increases, to look up the current percentage.
A landlord must provide their tenant with an approved form, Notice of Rent Increase, three full months before a rent increase takes effect. For example, if you receive this type of notice on April 5th, the three months that count towards the notice period are May, June, and July, and the rent increase would take effect on August 1st (assuming rent is paid on the 1st of the month). If your landlord does not raise your rent during a 12-month period, or raises it by less than the allowable percentage, they are not allowed to top-up a future rent increase to make up the difference.
These rules about rent increases apply to most types of rental housing, but there is one exception. If a tenant lives in non-profit housing that falls under section 2 of the Residential Tenancy Regulation, and their rent is also related to their income, the rules about rent increases do not apply.