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How Is Illinois Child Support Calculated For Overtime, Bonuses & Varying Income?

Updated on
November 1, 2019
Article written by
Attorney Kevin O'Flaherty

A reader left a comment asking how child support is calculated when one of the parents' income includes inconsistent payments such as overtime or bonuses.  The purpose of this article is to explain how Illinois domestic relationships courts deal with varying income, overtime, and bonuses when calculating child support obligations.  ​

‍As we have discussed in previous articles, Illinois Child Support Explained and Recent changes to Illinois Child Support, under the current Illinois law, the amount of a parent's child support obligation is based largely on the "net income" of the non-custodial parent.  Under the changes to Illinois child support law that will go into effect on July 1, 2017, the amount of a parent's child support obligation is based on the relative "net incomes" of both parents.  

‍There are three principal methods that domestic relations courts use to calculate "net income" when the obligor parent's income is inconsistent.  We expect these methods to also be used to calculate the recipient's net income under the new law after July 1, 2017. 

  • Method 1 - Using a Historical Average:  The most straight-forward method of calculating child support when income is inconsistent, but also the least accurate, is to calculate average income for a certain number of preceding months to arrive at a monthly income figure by which future child support will be determined.  Going forward if the average changes significantly, either party may go back into court to seek to have the original child support order modified. 
  • Method 2 - Using a Base Child Support Amount that is Supplemented Monthly: The most accurate method of calculating child support for inconsistent earners is for the court to establish a base child support amount, typically based on income before bonuses, overtime, or commissions.  This base amount will be supplemented monthly based on a percentage of any income over-and-above the base amount actually earned by the obligor.  This method requires the parties to work together on a monthly basis.  The obligor will submit earning statements to the recipient every month to prove that the amount actually paid in supplemental child support is appropriate. 
  • Method 3 - Periodical True Ups: In conjunction with each of the first two methods we discussed, the court may order a periodical true up process whereby child support will be paid either based on a historical average or a base amount plus a supplement, and at certain intervals the obligor will provide the recipient with pay stubs and W-2s to show the actual amount that should have been paid during the previous period.  The obligor will then either pay the difference to the recipient or receive a credit toward future payments. 
How Is Illinois Child Support Calculated For Overtime, Bonuses & Varying Income?
Author

Attorney Kevin O'Flaherty

Kevin O’Flaherty is a graduate of the University of Iowa and Chicago-Kent College of Law. He has experience in litigation, estate planning, bankruptcy, real estate, and comprehensive business representation.

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