A one-year fixed rate a year ago was about 2.5 per cent, Stampa said, and now it was more like 2.9 per cent.
"Point four of a per cent ... it's a tough one because it depends on the loan amount, it could be anywhere from $8, $9 a week increase in interest costs to $28, $30 [a week] from what I've looked at across my clients," Stampa said.
What it meant was there would be less discretionary spending going on, Stampa said.
"There will certainly be a tightening of purse strings and budgets for someone's personal expenses.
"We'll see a reduction in discretional spending, whether it be takeaways, alcohol, dinners out, buying clothes, there will be some changes that will have to be made."
People with multiple mortgages were also likely to start noticing the effects of not being able to write off interest costs - a recent Government change to try to cool the housing market.
"Not only are they going to be copping it with an increase in mortgage payments with interest rates going up, but they're also going to start copping it with not having as much tax efficiency because of the changes to the tax laws with investment properties."
Stampa said he was very interested to see how those people - often referred to as "mum and dad investors" - would cope with the increased financial pressure.
For businesses, the OCR increase was likely to be felt less directly, according to Whanganui business adviser Darren Hull.
"Obviously any businesses that are highly indebted and are carrying a lot of debt, then the increase in interest rates has an impact in terms of cash flow and repayment obligations."
He said the lift in the OCR was marginal, so he did not expect a big impact.
Following the OCR announcement, KiwiBank economist Jarrod Kerr said he expected that increase to be repeated regularly in the next two years.
"The RBNZ won't stop here," he said.
"We expect 25 basis point hikes will be delivered in October, November, February and May, with the OCR reaching 1.50 per cent by the middle of next year. We expect a considered pause of around 1.5 per cent. Although the RBNZ is signalling a continuation to 2 per cent in 2023."
That has led Hull to advise caution to his clients when they are considering any new debt.
Darren Hull. Photo / Supplied
"So what I've been saying to clients, as always, is when you look at making any decisions around what sort of debt you want to carry, you need to be allowing and providing for an increase in rates."
More expensive lending was unfortunate for businesses already facing widespread issues including employment issues, supply cost pressures and Covid-19 restrictions, he said.
A lot of households would now be spending more money on the mortgage, which meant less money being spent elsewhere in the economy, he said.
