How much should I save each month?

It depends on your goal, your timeframe, and the interest you earn. This calculator works backwards from your target to the monthly amount needed, taking into account any savings you already have and the return on your balance.

Does the interest rate make a big difference?

Over short periods the rate has only a small effect, but over many years it can noticeably reduce the amount you need to save, because the interest does some of the work. Try changing the rate to see the impact for your timeframe.

Is the interest taxed?

In New Zealand interest is taxable and resident withholding tax is usually deducted at your rate. This calculator shows the gross return, so your real after tax result will be slightly lower. Use a conservative rate to allow for that.

Savings Goal Calculator

This calculator works out how much you need to save every month to reach a savings goal by a set date, taking into account the interest your money earns along the way. Rather than guessing a round number and hoping it is enough, it works backwards from your target so you know exactly what a realistic plan looks like. You enter your savings goal, how much you already have put aside, the number of years you have to reach it, and the interest rate you expect your savings to earn. From these figures it returns the monthly amount to save, split into what you contribute yourself and what the interest adds on top, so you can see how much of the goal your own saving is doing versus how much the return is doing for you. This is useful whether you are saving for a house deposit, a holiday, a car, an emergency fund or any other target with a deadline. Because interest compounds monthly in this tool, even a modest rate makes a real difference over several years, so it is worth trying different rates and timeframes to see how they change the monthly figure. Remember that in New Zealand interest earned on savings is taxable, with resident withholding tax usually deducted at your rate, so your real after-tax growth will be a little lower than the gross rate shown here. Use a conservative rate and treat the result as a planning guide rather than an exact figure.

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Savings goal

Saved so far

Years

Interest rate

to save each month

You contribute$0

Interest earned$0

How it works

The calculator grows your current savings at the chosen rate, then works out the regular monthly amount needed to make up the rest by your target date. Interest compounds monthly, so part of your goal is met by the return on your balance rather than your own contributions.

Worked example

To reach $20,000 in 3 years with $2,000 already saved and 4% interest, you would need to save about $460 a month. Your contributions add most of it, while the interest adds a few hundred dollars over the three years.

Related calculators

Savings Calculator: project a savings balance.
Compound Interest Calculator: compound growth.
House Deposit Savings Calculator: save a house deposit.
Emergency Fund Calculator: build a safety buffer.

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