Key Highlights

  • The neutral rate is the level at which policy neither stimulates nor restrains the economy, and it must be estimated using models and judgement.
  • Kent said in August that the cash rate was around the top of the range of central estimates of neutral, and the September minutes used similar language.
  • The minutes raised the possibility that neutral has risen, which would make the previous 4.35% cash rate less restrictive than it was two years earlier.

The neutral rate cannot be observed directly, yet it sits at the centre of the Reserve Bank's judgement about whether a 4.60% cash rate is genuinely tight, and the September minutes raised the possibility that it has moved higher.

Are interest rates "high"? Central bankers tend to ask: high relative to what? The benchmark they use is the neutral interest rate, a concept that featured prominently in the Reserve Bank of Australia's latest policy discussion.

The minutes of the Monetary Policy Board's 28–29 September 2026 meeting, published on 13 October, record that members argued the previous 4.35% cash rate might be less restrictive than it had been two years earlier if the neutral rate had risen. The Board went on to lift the cash rate target to 4.60%, effective 30 September. Understanding the neutral rate helps explain why.

A definition in plain terms

The neutral rate is generally understood as the level of interest rates at which monetary policy is neither stimulating nor restraining the economy. Set the cash rate above neutral and policy tends to cool demand; set it below and policy tends to encourage spending and borrowing.

Assistant Governor (Financial Markets) Christopher Kent gave the RBA's working definition of the restrictive side in an August 2026 fireside chat titled "The Restrictive Stance of Monetary Policy": "Monetary policy is considered 'restrictive' if financial conditions are restraining aggregate demand".

The difficulty is that neutral is not published anywhere or measured directly. It has to be estimated using models and judgement. Kent noted that estimates of the neutral rate are highly uncertain, and the RBA refers to a range of central estimates rather than a single number.

Where the cash rate sits against that range

In August, Kent said "The current cash rate is around the top of the range of central estimates of the neutral rate". At that stage the cash rate was 4.35%, following three increases earlier in 2026. He concluded that "monetary policy in Australia is somewhat restrictive" and that "the three cash rate increases earlier this year are having their intended effects".

The September minutes used similar language. Financial conditions "remained somewhat restrictive", although the extent was uncertain, and the cash rate was around the top of central estimates of the neutral rate.

Being "around the top" of a range is an important nuance. It implies policy is likely on the tight side, but not by a wide or certain margin. If the true neutral rate were at the upper end of estimates, or above it, a cash rate in that vicinity would be applying relatively little restraint.

Why the neutral rate might move

Because neutral reflects the underlying balance between saving and investment in an economy, it is not fixed. Shifts in how much businesses want to invest, how much households want to save, global capital flows and productivity trends can all, in principle, move it over time.

The September minutes framed the question conditionally: if the neutral rate had risen, 4.35% might be less restrictive than two years earlier. The minutes present this as a possibility rather than a conclusion. But several observations in its recent communication would be consistent with demand holding up more than a clearly restrictive setting might imply.

  • Strong business investment. The Board's statement said "growth in business investment and debt is strong". The minutes said June quarter GDP was a little stronger than expected, led by private business investment, which rose more than 10% over the year.
  • Global AI-related demand. Kent pointed to "resilient global demand because of AI-related investment", and the statement listed AI-related demand pushing up technology goods prices among the upside inflation risks.
  • Persistent capacity pressures. Governor Michele Bullock said "Inflation is too high and has been driven by domestic capacity pressures."

These are the RBA's observations about the economy, not its explanation of the neutral rate. Read together, though, they illustrate why members might question whether 4.35% was as tight as estimates had suggested.

Not every signal pointed to loose conditions. The statement noted that "housing prices have fallen in most capital cities" and "new housing loans have declined noticeably". Household consumption slowed to a below-trend pace in the first half of 2026, and unemployment rose to 4.6% in August.

Scheduled mortgage payments were about 10% of household disposable income, near their 2024 peak, according to the minutes. Bullock noted that share was similar to when the cash rate was 4.35%.

This mixed picture is exactly why the neutral rate matters. Interest-sensitive areas such as housing were clearly responding, yet overall demand and inflation were still running too strong for the Board's liking. A higher neutral rate would be one way of reconciling those facts, though not the only one.

How the debate shaped the decision

The Board weighed a 25 basis point increase against holding. Arguments for holding centred on downside risks to activity, which members judged modest, and "all members judged that it was appropriate to increase the cash rate target by 25 basis points".

The broader case rested on inflation. Underlying inflation, measured by the trimmed mean, was 3.6% over the year to the June quarter 2026; headline CPI was 4.0% in the year to August. The statement concluded that "a further tightening in financial conditions is warranted to support a return of inflation to target". Uncertainty about neutral is relevant to that judgement: if policy was less restrictive than assumed, holding would have carried a greater risk of inflation staying high.

For households and businesses, neutral is not an abstract idea. If it has risen, a given cash rate delivers less restraint than it once did, and the level of rates needed to slow inflation could be higher than past experience suggests. If it has not, current policy may be tighter than it looks, with more of its effect still to come. Bullock said the full effect of rate changes takes 12 to 18 months.

The minutes leave further moves open, noting the Board would consider "increasing the cash rate target further if required." The next decision is scheduled for 2.30 pm on 3 November 2026.

The bottom line

The neutral rate is the level at which interest rates neither push nor hold back the economy, and it can only be estimated, with considerable uncertainty. In September, the RBA judged the cash rate to be around the top of central estimates, while members raised the possibility that neutral had risen, which would make 4.35% less restrictive than it once was. Strong business investment, AI-related demand and persistent capacity pressures sit alongside that possibility, and the uncertainty formed part of the backdrop to the decision to lift rates to 4.60%.