The International Monetary Fund has injected a new dynamic into Australia's monetary policy debate, urging governments to tighten fiscal policy even as markets increasingly expect the Reserve Bank of Australia to raise interest rates again. Traders now assign an 87% probability to a quarter-point hike at the RBA's September 29 meeting, a level that suggests the move is nearly the base case.
The RBA's cash rate currently stands at 4.35%, following three increases this year. Despite the elevated odds, the immediate market reaction was subdued, with the Australian dollar trading at US$0.7098, up 0.1%, and the S&P/ASX 200 edging 0.1% higher to 8,705.3. This muted response indicates that a September move is substantially priced in, even though the broader implications for mortgages, bank credit, and consumer demand remain uncertain.
Fiscal Policy Under the Spotlight
The IMF's latest assessment reframes the debate from a singular focus on the RBA to a two-part policy challenge. The Fund's staff recommended that the central bank be prepared to raise rates if necessary, while simultaneously urging federal and state governments to restrain demand through tighter budgets. This dual prescription comes amid concerns that energy-price shocks could keep inflation expectations elevated, with market pricing suggesting a cash rate near 4.85% by early 2027.
The growth outlook adds to the discomfort. The IMF projects real GDP growth of 1.9% in 2026 and 1.6% in 2027, according to its concluding assessment. The central concern is that resilient public and private demand could sustain inflationary pressures even as overall growth decelerates. Fiscal restraint would reduce the burden on the RBA, which would otherwise need to rely on higher borrowing costs to cool the economy.
Implications for Investors
The distinction between a rate hike driven by strong private demand and one necessitated by government spending and energy shocks is critical for investors. In the former scenario, corporate profits are better positioned to absorb higher rates. In the latter, discount rates rise while household purchasing power and corporate margins are already under strain.
A fourth hike would push the cash rate to 4.60%, inching closer to the 4.85% path embedded in market pricing. For households, the impact is tangible: a A$600,000 repayment mortgage with 25 years remaining and a 6.00% rate would see monthly payments rise from approximately A$3,866 to A$3,958 with a quarter-point increase, and to A$4,051 with a second. These figures, while illustrative, underscore how small policy changes can significantly drain discretionary spending.
Australian banks might see near-term support from higher asset yields, but the benefits are not one-sided. Higher rates can slow new lending and increase arrears, while funding and deposit costs also adjust. Retailers, residential developers, and other rate-sensitive sectors face the more direct risk of weaker volumes. A firmer rate path could lend marginal support to the Australian dollar, though slower domestic growth or a stronger US dollar might offset that effect.
The Case for Caution
The strongest argument against another increase comes from the RBA's own minutes. The August meeting noted that financial conditions had become somewhat restrictive, the cash rate was at the upper end of neutral estimates, demand for new housing loans had declined, and scheduled mortgage payments were near their 2024 peak. National housing prices were already about 1.5% below their March high.
These lags give the board reason to wait if incoming data weakens. However, the same minutes placed underlying inflation at 3.6%, above the RBA's 2% to 3% target, and recorded the board's willingness to respond if upside risks persisted. The RBA's August forecasts did not return inflation to the midpoint of the target until early 2028.
The September 29 decision ultimately hinges on whether the board sees enough demand destruction already in train to offset stubborn underlying prices and the new energy risk. Until that judgment is made, the 87% probability is a market price with a meaningful dissenting case, not a settled outcome.
