Calculate Child Support Payments in Illinois

Update: Illinois Child Support Guidelines Now Consider Both Parents' Incomes

When you've filled in the boxes above and clicked on the calculate button, you'll get a rough estimate of the amount of child support that the noncustodial parent will have to pay to the custodial parent under the "percentage based" formula.

However, you should know that Illinois has changed the formula in its child support guidelines to consider both parents' incomes. This could result in a different amount of support that the noncustodial parent has to pay. You may use the state's online Child Support Estimator, which takes into account the current "income shares" model for figuring support. You can also find the latest schedules and detailed support obligation worksheets on the Illinois Child Support Guidelines-Income Shares page.

Learn more about how child support works in Illinois, including allowed additions to basic support and how shared custody affects the amount of child support.

When Support May Deviate from the Illinois Child Support Guidelines

The amount of child support calculated under the Illinois guidelines won't necessarily apply in every situation. The state presumes that's the right amount. But you may argue that a different amount would be better in your situation. Whether you and the child's other parent have agreed on a support amount that departs from the guideline or a judge makes that decision for you, the judge will have to find that the guideline amount would be unjust or inappropriate. When making that finding, the judge will consider the child's best interests under the circumstances, including:

• both the child's and the parents' financial resources and needs
• the child's emotional and physical condition, including any educational and other special needs, and
• the standard of living the child would have enjoyed if the parents had stayed together.

(750 Ill. Comp. Stat. § 5/505(a)(2) (2022).)

Applying for Child Support in Illinois

Most parents apply for child support as part of the process of filing for divorce in Illinois. But there are other situations when you might need to request child support—most obviously, when you were never married to the child's other parent. In that case, the Division of Child Support Services (DCSS) in the Illinois Department of Healthcare and Family Services can help you get a child support order. You can enroll for services with DCSS online. As part of its free services, the DCSS can help with establishing the child's legal paternity (or parentage) and locating a missing parent.

How to Collect Child Support in Illinois

If you're having trouble collecting support payments, the DCSS can also help enforce court-ordered child support in Illinois through various methods, including by getting a wage withholding order, reporting delinquent parents to credit bureaus, suspending drivers' licenses or professional licenses, and placing a lien on bank accounts.

How to Change the Amount of Child Support

You (or the other parent) may request a modification of child support in Illinois. However, the judge won't change the existing support order unless you can show one of the following:

• there's been a substantial change in circumstances—such as a parent's reduced or increased income—since the existing support order was issued
• there's a difference of at least 20% (but no less than $10 per month) between the existing order and the amount that would be calculated under the Illinois child support guidelines (unless the existing order was based on an allowable deviation from the guidelines), or
• the change is needed to provide for the child's health care needs.

(750 Ill. Comp. Stat. § 5/510 (2022).)

The Illinois DCSS can review your existing child support order to see if it warrants a modification.