"Many people could save tens or even hundreds of thousands of dollars depending on the setup and repayment options they chose," she says.

"This year, just over 40% of fixed-rate mortgages are estimated to run out and so Kiwis should be searching out the best deal for their circumstances."

"People need to consider not only any short term sweeteners offered by mortgage lenders but the long term costs. Too many people with mortgages just consider the cost of the deposit and regular repayments. They neglect to first calculate how much they could save by increasing the level of repayments or frequency of repayments. In many cases even increases of relatively small amounts can make a huge difference."

Crossan said people could make significant savings if they could afford to pay off their mortgage more quickly. And the earlier the mortgage was paid off, the sooner people could start to build a nest egg to give them income when they chose to retire or work less hours.

"There are people who can afford to pay a bit extra but haven’t done the sums to work out how this will translate into substantial savings. As home loans are usually people’s biggest debt, this is one area that they need to focus on to make sure their mortgage is working in their best interests."

Tools available to help borrowers include the calculators on the commission's Sorted website and Good Returns Mortgage rate tables. Also borrowers should consider enlisting the help of a Mortgage Brokers. Yon can find one in your area Here