Typical monthly mortgage bills are expected to rise another $140 next week after official data showed inflation rose further in the June quarter.

Economists said Wednesday’s consumer price index – which showed inflation had risen to 6.1 per cent over the year to June – was in line with RBA forecasts and would therefore have little effect on the current outlook for interest rates.

It means the RBA is likely to unveil another 0.50 percentage point rate hike at its August meeting on Tuesday – raising the cash rate target to 1.85 per cent – rather than hiking by a turbocharged 0.75 percentage points.

The hike would be the central bank’s fourth in as many months as it tries to curb inflation by restricting the ability of households to spend.

Households with an average $500,000 mortgage will be paying $472 more every month than they were paying in May once major banks pass on the increase.

BIS Oxford senior economist Sean Langcake said the new inflation rate was slightly lower than the RBA anticipated, tempering fears about a potential 0.75 percentage point interest rate hike next Tuesday.

“There’s really only limited evidence that there’s any kind of breakout in wage-driven inflation, which is the stuff they’d be responsive to,” he said.

“A lot of it is being driven by volatile or imported inflation components.”

Inflation could peak earlier

The RBA expects the annual inflation rate to peak at 7 per cent later this year before falling closer to its 2 to 3 per cent target band in 2023.

But Mr Langcake said the outlook for consumer prices could be more optimistic than the RBA’s forecast. He predicted the pace of inflation could peak in the September quarter.

“We’ve probably seen the peak in quarterly numbers,” he said.

“You’d probably need an upside surprise to generate [7 per cent].”

Trimmed mean inflation – a measure of price rises that strips out volatile changes and is watched closely by the RBA when setting rates – rose to 4.9 per cent in annual terms in June, slightly higher than RBA forecasts.

But independent economist Saul Eslake said that won’t worry the central bank, which will see Wednesday’s figures as broadly in line with its expectations.

“I don’t think there’s anything in the data that warrants the RBA jerking the cash rate up by 75 basis points (0.75 percentage points),” he explained.

Inflation drivers still global

Mr Eslake said the key drivers of inflation continue to be international, with soaring fuel prices still the biggest single factor.

He said higher rates wouldn’t fix these problems, but would make it harder for businesses to pass on their higher costs to consumers without seeing their sales drop.

“The RBA raising rates is not going to fix supply chains, but what it is intended to do is slow the rate of growth of spending so that businesses have to think twice [about], or indeed can’t, pass on cost increases,” he said.

But Commonwealth Bank chief economist Gareth Aird said the effect of the three rate hikes since May hasn’t shown up in inflation figures yet and was unlikely to “shift the needle” over the September quarter.

“Inflation is red hot in Australia right now,” he said in a Wednesday note.

Mr Aird expects the RBA to continue raising rates until they are high enough to discourage households from spending more money.

This is known as the “neutral” rate – though no one knows where it is.

“We expect the RBA to take the policy rate to a contractionary setting by November 2022,” he said.

The Reserve Bank will hand down its next rate decision on August 2.