Estimating your income
If you are a paying parent, the amount you must pay in child support depends on how much you earn. We usually assess your payments based on your income from either the previous year or two years. However, you may prefer to estimate your income if you are earning less now than you were in previous years.
When can you estimate your income?
You can choose to estimate your income for child support if your current income has fallen by 15% or more from the income on which your current assessment is based. Your estimation must be received before the end of the year for which you are estimating.
You cannot estimate your income if your child support assessment has been determined by a Court order or an administrative review. Estimations only apply to paying parents assessed under the formula assessment, and excludes voluntary agreements, court orders & domestic maintenance cases.
How do you estimate your income?
If you decide to estimate your income:
- you are responsible for getting it right
- you need to fill in an Estimate of income for child support assessment (IR104) form, or complete this form online.
The estimation starts from the beginning of the month when we receive your completed Estimate of income for child support assessment (IR104) form. The amount you had to pay for previous months will not change.
An example of how a paying parent estimates their income is provided on this site. For more help, please call us on 0800 221 221 or see Child support - estimating your income (IR151). The forms and guides are also available by calling our 0800 self-service line on 0800 257 773.
Please contact us immediately on freephone 0800 221 221 if:
- your income changes after you have estimated it
- you have made a mistake in your estimate.
In these circumstances, you may need to make a new estimation to avoid an underestimation penalty. Information on changing or cancelling your estimate is provided on this site.
Date published: 13 May 2010
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