KiwiSaver vs Debt Payoff Calculator

This calculator helps you decide whether spare cash is better put into KiwiSaver or used to pay off debt in New Zealand, by comparing the guaranteed return from clearing debt against the expected return from investing. It is one of the most common money questions, and the answer usually comes down to a head-to-head of rates. Paying off debt delivers a guaranteed return equal to the interest rate you stop paying: clear a credit card charging twenty percent and you have effectively earned a risk-free twenty percent. Extra KiwiSaver, by contrast, offers an expected return that is usually lower and never guaranteed, riding the ups and downs of markets. So when your debt rate is higher than your expected KiwiSaver return, paying the debt almost always comes out ahead. You enter the spare amount, your debt interest rate and your expected KiwiSaver return, and the calculator shows the guaranteed interest you would save by paying the debt, the expected gain from investing instead, and which is ahead. One important caveat sits above this: contribute enough to KiwiSaver first to capture the full employer and government contributions, because that free money beats almost everything. Beyond that minimum, this comparison applies. Returns are not guaranteed; general information, not advice.

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Paying debt wins by $700 a year, and it is guaranteed
first-year benefit of each option
Debt interest saved$1,000
KiwiSaver expected gain$300

Debt saving is guaranteed; KiwiSaver return is expected and at risk. Capture the full employer and government KiwiSaver contributions first. General information, not advice.

How it works

The debt interest saved is the spare amount times your debt interest rate, the return you lock in by clearing that debt. The KiwiSaver expected gain is the spare amount times your expected return, which is uncertain. The calculator compares the two first-year figures and reports which is larger, noting that the debt saving is guaranteed while the KiwiSaver gain is not.

Worked example

With 5,000 dollars spare, paying off debt at 20 percent saves 1,000 dollars of interest for certain, while a 6 percent KiwiSaver return is an expected 300 dollars. Paying the debt wins by about 700 dollars, and it carries no risk.

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