Should I put my bonus into KiwiSaver?

A bonus is taxed as income either way. Putting the net amount into KiwiSaver lets it grow until retirement or a first home, but it is locked away. Taking it as cash keeps it accessible. The calculator compares the long-term growth against the cash today.

Is a bonus taxed if I put it in KiwiSaver?

Yes, a bonus is taxed as income, so this compares the after-tax bonus taken as cash with the same after-tax amount contributed to KiwiSaver and grown over time.

What is the catch with KiwiSaver?

KiwiSaver is locked until 65 or a first home, so the growth comes at the cost of access. If you might need the money sooner, that flexibility has real value.

Bonus to KiwiSaver Calculator

This New Zealand calculator compares taking a work bonus as cash against directing it to KiwiSaver, including the long-term growth. You enter your bonus, tax rate, and years to retirement, and it shows the after-tax bonus you would receive now against what the same amount could grow to in KiwiSaver, while noting that KiwiSaver is locked away until 65 or a first home. It helps you weigh money in the hand today against a larger sum later, so a one-off bonus can be a deliberate choice rather than a quick spend.

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Bonus amount (before tax)

Your tax rate

KiwiSaver return

Years to retirement

what the bonus could grow to in KiwiSaver by retirement

Net bonus as cash now$0

Tax on the bonus$0

Growth in KiwiSaver$0

A bonus is taxed as income whether you take it or contribute it, so this compares the same after-tax amount. KiwiSaver growth assumes a steady return and is not guaranteed, and the money is locked until 65 or a first home. Estimate only, not financial advice.

How it works

The calculator works out your after-tax bonus by applying your tax rate, which is what you would receive as cash. It then grows that same net amount at your KiwiSaver return over the years to retirement, to show what it could become if contributed instead. The difference is the growth you give up by spending it now, set against the flexibility of having the cash available.

Worked example

A $5,000 bonus taxed at 30% nets $3,500 as cash. Contributed to KiwiSaver and grown at 6% for 25 years, that $3,500 could become around $15,000. The trade-off is that the KiwiSaver money is locked away until retirement or a first home.

Related calculators

KiwiSaver Calculator: project KiwiSaver.
Bonus and Commission Tax Calculator: tax on a bonus.
Compound Interest Calculator: how money grows.
Managed Fund vs KiwiSaver Calculator: fund or KiwiSaver.

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