Mortgage Refix Savings Calculator NZ

This calculator shows how much interest you save by refixing your New Zealand mortgage at a lower rate, both in the first year and across the whole new fixed term. Refixing is the decision almost every Kiwi mortgage holder faces every year or two: when a fixed term ends, you pick a new rate for the next term, and the rate you land on has a big effect on what the loan costs you. When rates fall, refixing at the lower rate puts real money back in your pocket, and this tool makes that saving concrete. You enter your remaining loan balance, your current fixed rate, the new rate you can refix at, and the length of the new fixed term, and the calculator works out the interest you would pay at each rate and the difference. The headline is the saving per year, with the total saving over the fixed term shown alongside, so you can see what shopping around or negotiating a sharper rate is actually worth. The saving is based on interest on the balance, and in practice it eases slightly as the loan reduces over the term. Note this assumes you are refixing at the end of a term, not breaking early, which would usually trigger a break fee. Estimate only, not financial advice.

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Loan balance

Current rate

New rate

New fixed term (years)

$5,000

interest saved in the first year

Saved over the term$10,000

Rate drop1%

Monthly saving$417

Based on interest on the balance; the saving eases slightly as the loan reduces. Assumes refixing at term end, not breaking early. Estimate only, not advice.

How it works

The first-year saving is your loan balance times the rate drop, which is the current rate minus the new rate. The saving over the term is that annual saving times the number of years in the new fixed term, and dividing the annual saving by 12 gives the monthly figure. It is a clean interest-on-balance estimate.

Worked example

Refixing a 500,000 dollar balance from 6.99 percent to 5.99 percent is a 1 percent drop, saving about 5,000 dollars of interest in the first year, roughly 417 dollars a month, and about 10,000 dollars over a 2-year fixed term.

Related calculators

Mortgage Repayment: repayments.
Break Fee: cost of breaking early.
Fixed vs Floating: rate type.
Rate Comparison: compare rates.

Frequently asked questions

What does refixing a mortgage mean?

When a fixed term ends, you choose a new fixed rate for the next term, which is called refixing. If rates have fallen, refixing at a lower rate cuts your interest cost; if they have risen, your payments go up.

How much does a lower rate save?

The annual saving is roughly your loan balance times the drop in rate. A 1 percent drop on a 500,000 dollar loan saves about 5,000 dollars of interest in the first year, with the saving easing slightly as the balance reduces.

Should I break my fixed rate early to refix?

Maybe, but breaking a fixed rate early usually triggers a break fee that can wipe out the saving. This tool assumes you are refixing at the end of a term. Check any break cost separately before switching mid-term.