Interest Rate Rise Impact Calculator NZ

This calculator shows how a rise in your mortgage interest rate would change your repayments, so you can see the impact before it happens rather than after your fixed rate rolls off. Most New Zealand mortgages are fixed for one or two years, and when the term ends you refix at whatever rate is on offer, which may be higher than your current one. You enter your remaining mortgage balance, current interest rate, the rate rise you want to test (1% or 2% is a good starting point), and how many years remain on the loan. The calculator works out your current table repayment and your new repayment at the higher rate, then shows the extra you would pay each month and each year. It uses the same logic banks apply when they stress test new lending against a higher test rate, giving you a realistic sense of how exposed your budget is to rising rates. Use the results to decide whether to pay down debt faster while rates are lower, build a cash buffer, split your loan across different fixed terms, or simply plan ahead for a bigger repayment. This is an indicative estimate based on standard table loan repayments and does not account for fees, offset accounts or changes to your loan structure.

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Compares table repayments at your current rate and the higher rate over the remaining term. Banks test new lending against a higher "test rate" for the same reason. Estimate only, not a loan offer.