Mortgage pain as RBNZ set for record hike

New Zealand could see an unprecedented 75 basis points hike in the official cash rate when the Reserve Bank considers its last shift for the year.

Already at 3.5 per cent - up from 0.25 per cent in October last year - Kiwi lenders believe the 75bp rise for the cash rate (OCR) not only possible on Wednesday, but likely.

A Barclays survey of 19 market participants showed 14 expected the triple-hike, with five betting on the 50bp double-hike.

Westpac NZ's acting chief economist Michael Gordon said an incredible 100 basis point lift was not out of the question, saying the RBNZ had "fallen behind the pace" in its fight against inflation.

"While we're picking a 75 basis point increase next week, we acknowledge that both a 50 point and a 100 point increase are genuine possibilities as well," he said.

"The RBNZ is still some way from where it needs to be. And with little room for delay, we think that the RBNZ will deliver a larger 75 basis point increase in the OCR this time, taking it up to 4.25 per cent."

Westpac and ANZ has upped its forecast for the OCR peak to 5.0 per cent.

Kiwibank is calling Wednesday's decision a "coin toss" but siding on the 75bp lift as "the war on inflation is ongoing".

"The RBNZ must remain hawkish in a bid to soften inflation expectations," chief economist Jarrod Kerr said.

Like its Australian equivalent, the RBNZ has a remit to keep headline inflation - measured through the consumer price index (CPI) - between one and three per cent.

Given CPI inflation was last measured at 7.2 per cent in the September quarter, it has plenty of work to do.

That figure is down slightly on the June quarter, and just below Australia's figure of 7.3 per cent.

While those figures are both the highest in over a decade, they are below the OECD average, measured at 10.5 per cent in September - with half of the 38 OECD countries measuring double-digit growth.