Overpayment Impact Calculator
Frequently asked questions
How much money does overpaying a NZ mortgage save?
Even small regular overpayments deliver significant compounding savings. Paying an extra $100 per week on a $500,000 mortgage at 6.5% over 30 years saves over $130,000 in interest and reduces the loan term by approximately 6 years. Extra payments reduce the principal faster, which lowers the interest charged on every subsequent payment.
Can I make extra repayments on a fixed NZ mortgage?
It depends on your lender and loan structure. Most NZ banks allow some extra repayments on fixed mortgages — commonly up to $500–$1,000 per month above the regular payment — without a break fee. Check your loan agreement or contact your bank to confirm the limit. Floating portions allow unlimited extra repayments with no penalty.
Is it better to overpay my mortgage or invest the money?
If your mortgage rate is 6.5% and you can earn more than 6.5% after tax on investments, investing may be mathematically superior. However, mortgage overpayments provide a guaranteed risk-free return equal to your interest rate — something investments cannot guarantee. Many NZ homeowners split the difference: overpay a portion and invest a portion.
Does overpaying shorten the loan term or reduce my repayments?
When you overpay a NZ mortgage, most lenders apply extra payments to reduce your outstanding balance — which shortens the loan term while keeping your regular payment the same. Some lenders allow you to instead reduce your regular repayment amount. Shortening the term typically saves more interest overall.