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Estimation of income for child support

(To use this service you need to be registered for myIR Secure Online Services)  

About this service

You can use this service to estimate your taxable income for your child support assessment. It's the same as completing the Estimate of income for child support assessment (IR104) form.

When to use this service

Use this service if you pay or receive child support during the tax year (1 April to 31 March).

Note
  • Your estimated taxable income must be at least 15% lower than the taxable income we used to work out your child support assessment.
  • You can make another estimate of taxable income before or during the child support year, but not after. You can use this online form or send us a written request.

This form will take about 10 minutes to complete.

What you will need

You'll need your IRD number, which you'll find on your payslip or notice of assessment/entitlement.

For us to accept this income estimation, as well as submitting the "online estimation", you will also need to send us proof of your income. This can be:

  • two new payslips showing your reduced income, or
  • a letter from your employer or accountant stating your reduced income details, or
  • your WINZ number if you're on a benefit.
After you finish

After we receive your application we'll reassess your child support.

If your income changes again during the year, you can submit another form to make sure you are still assessed correctly.

This service may require you to send confidential information to Inland Revenue so it is located on a secure part of our website to prevent unauthorised interception. If you are unable to access this service, your browser and/or firewall settings may need updating.

Inland Revenue takes online security very seriously. We have systems in place to protect the information you provide us, and regularly update our standards and technology to provide protection for your personal information.

You play an important role in protecting your information by taking basic precautions to protect your computer and data. You should keep your computer secure, only deal online with people and organisations you know and trust, and check that your personal information travels across the internet on secure connections.

There are many resources about computer security (such as websites, books and magazines) that can help guide you on what security precautions are appropriate for your situation.