In New Zealand, there is no single flat “child support amount” – it is calculated using a formula that depends mainly on your income, the other parent’s income, and how much care each of you provides.

Key numbers for 2025

  • Inland Revenue updates key child support rates every year on 1 April.
  • From 1 April 2025 to 31 March 2026, the minimum child support a liable parent must pay under a formula assessment is $1,175 per year , which is about $22.60 per week.
  • The formula also uses a living allowance (an amount of income that is protected for your own living costs) of $29,909 per year , or $33,523 if you are on a Supported Living Payment.

These figures are used inside the Inland Revenue calculator to work out the exact payment for your situation.

How the formula works (in plain English)

Inland Revenue (IRD) uses a standard formula assessment for most cases.

Very simplified, it looks like this:

  1. Work out each parent’s child support income
    • Start from taxable income.
    • Subtract the living allowance and some costs for other dependent children you support.
  1. Work out each parent’s percentage of combined income
    • Your adjusted income is divided by the total of both parents’ adjusted incomes.
  1. Compare this with the percentage of care
    • If you have less day‑to‑day care than your income share, you are usually the one who pays.
    • Shared care (at least 28% of nights) will usually reduce what you pay.
  1. Apply the child support table
    • The formula applies a cost‑of‑children percentage to the combined income , depending on the number and ages of the children.
 * Your share of that cost becomes your annual child support, but it cannot go below the **minimum $1,175/year** unless a special rule applies.

Because of all these moving parts, two people on the same income can pay very different amounts if care splits or other children differ.

Typical tools and examples

To get a realistic estimate for your case, use IRD’s official child support calculator :

  • You enter:
    • Your income
    • The other parent’s income
    • Number of children and their ages
    • How many nights the children are with each parent
  • The calculator then gives an estimated weekly or yearly amount based on the current formula.

On forums like r/PersonalFinanceNZ and r/newzealand, people often report:

  • Payments ranging from just the minimum (around low‑20s per week) up to several hundred dollars per week for higher earners.
  • Big changes in assessments when:
    • Income jumps or drops
    • Care changes from “primary care” to more “shared care”
    • New children in a new relationship are added to the calculation.

These are personal experiences, not official rules, but they give a sense of the range.

Private vs IRD child support

You can either:

  • Use IRD-assessed child support
    • IRD works out the amount and collects/enforces payment.
  • Make a private agreement
    • You and the other parent agree on an amount yourselves.
    • This can be higher or lower than the formula, but if things go wrong, you may need IRD or the courts to help enforce anything.

Many separating couples try a private agreement first, especially if they get on reasonably well, then move to IRD if conflict arises or if one person stops paying.

Fast answers to common questions

  • “What is the absolute minimum I’ll pay?”
    • For 1 April 2025–31 March 2026, the minimum standard rate is $1,175 per year (about $22.60 per week) per liable parent, unless a specific exemption applies.
  • “Can child support be $0?”
    • It can be nil in limited situations (for example, very low income plus care percentage and certain benefit situations), but for most working parents there will be at least the minimum amount.
  • “Does it go up every year?”
    • Yes, the key figures (living allowance, minimum rate, inflation factor) are indexed annually , so amounts usually rise each 1 April.

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Wondering how much is child support NZ in 2025? Learn how Inland Revenue calculates child support, current minimum rates, and how income and care splits affect what you pay or receive.

Information gathered from public forums or data available on the internet and portrayed here.