Child Support Guidelines in Illinois
The model, the factors, and the official table for Illinois.
Reference only — no accounts, no personal data collected.Illinois sets child support through statewide guidelines. This page explains the calculation model Illinois uses, the factors that go into it, and where to find the official support schedule.
The Model Used in Illinois
Illinois uses the Income Shares model. The guideline combines both parents' incomes as if the child lived in an intact household, then splits the obligation in proportion to each parent's share of that combined income.
Factors Illinois Considers
- Combined gross income of both parents
- Allowable deductions (taxes, prior support, other children)
- Each parent's proportional share of the combined income
- Parenting time / overnights with the child
- Work-related childcare costs
- Health insurance premiums and uninsured medical expenses
- Educational or extraordinary expenses where the guidelines allow
Base Obligation Table
The dollar amounts come from the Illinois Child Support Schedule, published by the Illinois Department of Healthcare and Family Services. The schedule turns the inputs above into a monthly obligation. See the official schedule on the agency site: https://www.illinois.gov/hfs/childsupport/Pages/default.aspx.
Illinois switched to an income-shares model with a parenting-time credit in 2017.
Frequently Asked Questions
What model does Illinois use for child support?
Illinois uses the Income Shares model. See "The Model Used in Illinois" above for how it works.
Does parenting time affect support in Illinois?
Yes. Illinois adjusts the obligation for the number of overnights the non-custodial parent has, because shared parenting lowers the custodial parent's direct costs.
Where do I find the official Illinois support table?
The official schedule is published by the Illinois Department of Healthcare and Family Services. A link is in the "Base Obligation Table" section above.
Is this the final amount I will pay or receive?
Not necessarily. Courts can deviate for extraordinary medical needs, private school, or travel costs. Use the official schedule or a family-law attorney for a case-specific number.