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Child support
Turuki Tamariki

How much child support will you have to pay?

We use a simple four-step calculation (often called the child support formula) to work out how much child support a paying parent must pay. The result is the formula assessment.

The four steps in the child support formula are:

  1. determine the paying parent's taxable income
  2. deduct a living allowance from the income amount
  3. multiply the result by a percentage rate
  4. divide the final amount into 12 equal monthly amounts, which must be paid by the 20th of each month.

You can see more details on these four steps. If you would like to work through the child support formula for your own circumstances, you can use the child support liability calculator (available in the work it out section of our site), or the manual step-by-step process given in Calculating child support (IR150).


Date published: 30 Oct 2004

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