The ACT's CPI rent cap — how it works and what it means for you

The ACT is different

Every other Australian state and territory allows landlords to increase rent by any amount — subject only to notice requirements and the right to apply to a tribunal if the increase is deemed excessive. The ACT is different. Under the Residential Tenancies Act 1997 (ACT), rent increases in most residential tenancies are linked to the Consumer Price Index (CPI) — specifically, Canberra's CPI figure as published by the Australian Bureau of Statistics.

How the cap works

When a landlord wants to increase rent, they must give the tenant 8 weeks' written notice. The maximum increase they can impose without applying to ACAT is the CPI increase for Canberra, as reported for the most recent 12-month period. If inflation (CPI) was 3.5% over the past year, the landlord can increase rent by up to 3.5% without further justification.

What is the current CPI figure?

The ABS publishes quarterly CPI figures. For the purposes of the ACT rent cap, the relevant figure is the annual CPI change for 'Canberra — All Groups' for the most recent 12-month period. As of early 2026, this figure has been declining from post-pandemic highs. Tenants and landlords should check the most recent ABS CPI release for the current applicable figure.

• •2023: CPI peaked around 7–8% — a difficult year for ACT tenants, even with the cap
• •2024: CPI moderated to approximately 3–4%
• •Early 2026: CPI continuing to moderate toward the Reserve Bank's 2–3% target range

Can a landlord exceed the CPI cap?

Yes, but only by applying to ACAT. A landlord can apply to ACAT for permission to increase rent above CPI if they can demonstrate that the increase is justified — for example, because the current rent is significantly below market rate, or because they have made substantial capital improvements to the property. ACAT will make an assessment based on the evidence.

• •The burden is on the landlord to justify the above-CPI increase
• •ACAT considers market rents, property improvements, and the landlord's legitimate costs
• •Tenants can oppose the application and present their own evidence

What if the landlord exceeds the cap without ACAT approval?

If a landlord issues a rent increase notice that exceeds the CPI cap without an ACAT order, the increase above the cap is void. You are not required to pay the excess. Write to the landlord explaining the cap, and if they insist, apply to ACAT. In the ACT, the tenancy authority is robust in enforcing these rules.

Is a CPI cap good policy?

The ACT's CPI-linked rent cap is the most direct form of rent regulation in Australia. Advocates argue it provides genuine rental security and prevents opportunistic rent hikes. Critics argue it discourages landlords from investing in the ACT market and that CPI does not accurately reflect landlord costs. The policy debate continues, but for current ACT tenants, the cap is law and can be relied upon.