Key Highlights

• Australia’s annual Inflation rate increased to 4.0% in August from 3.5% in July.

• Housing prices rose 5.7% over the year and were the largest contributor to annual inflation.

• Transport prices increased 5.6%, while automotive fuel jumped 14.8% in August.

• Annual trimmed mean inflation remained at 3.6% for a third consecutive month.

Australia’s inflation picture became more complicated in August 2026 as headline inflation accelerated while the underlying measure remained unchanged. Annual CPI rose to 4.0% from 3.5% in July, with housing and transport accounting for much of the pressure. The split between headline and underlying inflation is important because it helps show whether price growth is being driven by broad, persistent pressures or by unusually large moves in particular categories such as fuel and electricity.

Housing Becomes the Biggest Inflation Driver

Housing prices rose 5.7% over the year, making the category the largest contributor to annual inflation. The CPI housing category does not include Mortgage servicing costs. Instead, it captures expenses including rents, utilities, new dwelling construction, council rates and property repairs.

New dwelling prices increased 5.4% over the year as builders passed through higher material and labour costs. This distinction matters when interpreting the CPI: higher interest payments on mortgages can strain household budgets, but they are not directly recorded as housing inflation in the CPI measure.

Fuel Pushes Transport Costs Higher

Transport prices rose 5.6% over the year. Automotive fuel was a major contributor, jumping 14.8% in August after increasing 7.5% in July. Higher global oil prices and the remaining unwind of temporary federal fuel excise relief contributed to the move.

Fuel can produce large short-term swings in headline CPI because global energy prices can change quickly. It also has broader economic significance because transport costs can feed into household expenses and Business distribution costs.

Why Underlying Inflation Tells a Different Story

Annual trimmed mean inflation held at 3.6% for a third straight month, while the monthly trimmed mean slowed to 0.2% from 0.5% in July. Trimmed mean inflation removes some of the largest price increases and declines to give a clearer view of underlying price pressures.

Automotive fuel and electricity were excluded from the August trimmed mean calculation and were important reasons headline inflation moved further above the underlying measure. The result suggests that volatile components contributed substantially to the headline acceleration, although underlying inflation remained above the RBA’s 2% to 3% target range.

What Does This Mean for Interest Rates?

The August CPI figures followed the RBA’s decision to lift the cash rate by 25 basis points to 4.60%, its fourth increase of 2026. The Central Bank had pointed to stronger-than-expected inflation outcomes and upside risks to prices, including higher global energy costs.

The August data were not available when the September rate decision was made. They therefore become part of the information set for subsequent meetings, alongside the full September-quarter inflation report, labour-market conditions and household spending.

What to Watch Next

The full September-quarter CPI will be important for assessing whether underlying inflation is easing or remaining persistent. Fuel prices, housing costs, services inflation, household spending and labour-market data will also help shape the next stage of the inflation and interest-rate outlook.