Vacancy rates are the most widely used single measure of rental market conditions in Australia. This guide explains how they are measured, where the data comes from, what methodological differences between providers mean for investors, and what drives vacancy over time.
Vacancy rate is expressed as:
Vacancy rate = (Vacant rental properties ÷ Total rental stock) × 100
The challenge is defining "vacant" and "total rental stock." Different providers measure this differently, which is why SQM Research and REIA figures for the same suburb can diverge.
SQM Research derives its figures from online listing data. A property listed for rent for more than 21 days is counted as vacant. This gives monthly, suburb-level data. REIA and state bodies survey property managers quarterly and ask how many properties they have listed as vacant. Both are estimates. Neither captures perfectly the full picture.
Method: Online listing platforms. Counts properties listed for rent for more than 21 days as vacant.
High frequency, suburb-level, independent from industry bodies.
May undercount off-market vacancies. Platform coverage varies in smaller markets.
Method: Survey of property managers and real estate agencies. Managers report on properties under management.
Covers off-market and off-platform rentals. Direct industry source.
Quarterly lag. Not available at suburb level. Response rates vary.
Method: Ground-truth. Ask directly how long properties are taking to lease and what concessions (if any) are needed.
Most current. Captures market nuance not visible in aggregate data.
Qualitative and anecdotal. Requires outreach. May reflect single agency view.
Vacancy is directly affected by new rental supply entering the market. A suburb with strong rental demand but a large pipeline of new apartments or houses under construction may see vacancy rise as that stock completes. SuburbScanner tracks approved new construction pipelines and planning constraints as part of its supply tightness research dimension.
Employment is the structural driver of sustained rental demand. Markets dependent on a single major employer (a mine, a government facility, a large manufacturer) carry vacancy risk if that employer reduces headcount or exits. Diversified employment bases — healthcare, government services, agriculture, transport — provide more durable rental demand.
A suburb with very high investor ownership can experience rapidly elevated vacancy if sentiment shifts and investors sell simultaneously, because sale stock also exits the rental pool. Conversely, in markets with strong owner-occupier participation, rental stock is more stable and less sensitive to investor cycles.
Some markets show seasonal vacancy patterns. University towns see peaks at the end of academic years. Tourism-heavy markets see peaks in off-seasons. Resource towns can show spikes when project phases end. Understanding whether vacancy in a market is structural or seasonal is essential to interpreting the data correctly.
Vacancy is one input into SuburbScanner's supply tightness research dimension. The model considers vacancy alongside listing stock levels, new construction approvals, and qualitative employment context to assess the structural depth of rental demand in each market.
A market with 0.8% vacancy and one dominant employer is scored differently to a market with 0.8% vacancy and diversified employment across healthcare, agriculture, and government services. The number alone is necessary but not sufficient.
Vacancy data in SuburbScanner is sourced from SQM Research and reflects Q4 2024 / Q1 2025 conditions. It should be verified directly with local property managers before any investment decision.