What is a sinking fund?

A sinking fund is money you set aside regularly to cover a known future cost, such as annual rates, insurance or car registration. Instead of a big bill landing all at once, you build the money up steadily so it is ready when the bill arrives.

How do I work out my sinking fund amount?

Add up your known yearly costs, then divide by how often you want to set money aside, weekly, fortnightly or monthly. This calculator does that across several costs so you know the single regular amount to put away.

Why use a sinking fund?

It turns lumpy, predictable bills into a smooth, manageable habit, so the big ones never blow your budget or push you into debt. It is one of the simplest ways to take the stress out of irregular expenses.

Sinking Fund Calculator

This New Zealand calculator works out the regular amount to set aside for known future costs like rates, insurance and car registration. Rather than a big bill landing all at once, a sinking fund builds the money up steadily so it is ready when the bill arrives. You enter your yearly costs, and the tool shows the single weekly, fortnightly or monthly amount to put away, turning lumpy bills into a smooth, easy habit.

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Rates per year

Insurance per year

Car rego, WOF, servicing

Other annual costs

to set aside per week

Per fortnight$0

Per month$0

Total per year$0

Set the amount aside in a separate account so it is there when the bills land. Review yearly as costs change. A sinking fund is one of the simplest ways to avoid bill shock. Estimate only.

How it works

The calculator adds up your known yearly costs, then divides the total by the number of weeks, fortnights and months in a year to show the regular amount to put away. Setting that amount aside, ideally in a separate account, means the money is ready when each bill arrives, so a big annual cost never blows your budget or pushes you toward debt.

Worked example

With $3,000 rates, $2,400 insurance, $1,200 of car costs and $1,000 of other annual costs, the total is $7,600 a year. That is about $146 a week, $292 a fortnight or $633 a month to set aside, so every one of those bills is covered when it lands.

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