Interest rates are rising, but Whangarei business owner Tonya Russell says the prospect of bigger loan repayments hasn't really crossed her mind yet. She has her mortgage divided into smaller loans, set across different terms, with an offset facility, to minimise her exposure to rate changes.

The mortgage on her business property is fixed, with interest-only payments. "I'm risk averse," she says. "I hope I get a good rate [when I refix]. But the economy is out of my control so I don't worry about it. If I have to earn more money I will."

Your mortgage could become thousands of dollars more expensive in the next couple of years - but new research shows, like Russell, New Zealanders aren't worried. A survey of almost 2000 homeowners, conducted by New Zealand Home Loans, found more than half were either unconcerned or neutral about the potential for future interest rate rises.

Economists expect retail interest rates to rise steadily over the coming years, driven by global and local factors.

Edge Mortgages founder Glen McLeod says people should be able to handle interest rate increases.

Infometrics predicts two-year fixed home loan rates of 5,65 per cent by the end of next year and 6 per cent by the end of 2019, from a median rate of 5.14 per cent now. It says five-year rates could hit 7.16 per cent by the end of 2020, from 5.99 per cent now.

If you have a $500,000 mortgage over 25 years, you will pay $1367 a fortnight or $35,542 a year on 5.14 per cent. But if you refix for Infometrics' predicted 5.65 per cent at the end of next year, your bill will rise to $1437 a fortnight, or $1820 more a year.

At 7.16 per cent, that same mortgage would cost $1654 a fortnight. 

Mortgage broker Glen McLeod said most of his clients would be unconcerned. Applications for home loans were assessed on a higher interest rate than would be applied, he said.

"We're already factoring in well over 7 per cent. The affordability is actually there. People will have to not spend money on the things they are at the moment because they will have to have that cash available. It's just part of the cycle."

He said he was monitoring the interest rate predictions and helping clients to take sensible fixes that would offer them protection from future increases. In some cases, it made sense to split a loan over staggered terms, he said, so the whole loan did not roll off at the same time.

"You can minimise rate shock by staggering loan terms."

The survey showed people were concerned about their ability to cut spending, particularly on consumer items such as household electronics, tools and sports goods where 47 per cent of respondents found difficulty controlling spending and secondly for services like household maintenance at 46 per cent.

Entertainment, such as concerts and movies, and bad habits like cigarettes and alcohol were two other areas where respondents expressed difficulty in managing their spending.

"It is refreshing to see that homeowners are not overawed by the prospect of future rate rises. Not just because rates aren't expected to change dramatically any time soon but more because if we are to seriously tackle the amount of household debt we have as a nation, it is less about the actual interest rate and more about the rate home loans are paid off," said NZ Home Loans chief executive Julian Travaglia.

"From that perspective, the fact people are recognising they need to curb spending on unplanned items is a good thing, as it allows money to be channelled into their largest expense - their mortgage. And while a bit of belt tightening may seem difficult initially, when combined with a right home loan structure, the average household in the long run can save thousands of dollars in interest.

"That rather than sweating about interest rates, has been shown to be a much clearer way to a future free of financial stress."