ILLINOIS SUPPORT GUIDELINE
Illinois child support calculator & worksheet
Illinois child support uses state-specific income definitions and guideline rules. A base child support worksheet is available with the scope and exclusions listed below. Use this guide to check income requirements, sources, and limits before completing your worksheet.
Current module status
| State | Illinois |
|---|---|
| Status | Active base worksheet module |
| Guideline model | income shares monthly table |
| Primary income field | Combined monthly net income |
What the worksheet asks for
The calculator workflow starts with the selected state, then walks through both parties’ income, assets, debts, and state-specific particulars. Countable income streams feed each party’s formula income; balances and non-automated adjustments are disclosed separately. Common categories include wages, bonuses, dividends and interest, business or company income, self-employment adjustments, existing support obligations, debts assigned by order, health insurance, child care, tuition, extraordinary expenses, and parenting time.
Sources and limits
- Uses the Illinois HFS 2026 Income Shares Schedule of Basic Child Support Obligations based on net income, effective March 20, 2026.
- The HFS income-shares page states Illinois annually updates both the Gross to Net Income Conversion Table and the Income Shares Schedule, and the schedule was most recently revised effective March 20, 2026.
- This base module allocates the schedule obligation by each parent’s share of combined monthly net income.
- Standardized gross-to-net conversion, health insurance, child care, extracurricular expenses, shared physical care, multi-family adjustments and deviations require the full Illinois worksheet.
- For combined monthly net income above the last encoded HFS schedule range, this module uses the last schedule amount and flags the case for review.
Official Illinois source used for review
Run the calculator
Open the free support calculator, select Illinois, complete the state worksheet, and print or export the output for review.
Frequently asked questions
Is this the official Illinois court calculator?
No. It is an independent educational estimate. Courts can order a different amount when the evidence, local rules, or statutory deviation factors justify it.
Can I use the output in court?
The worksheet output is designed to be clear and printable, but each litigant is responsible for checking local filing rules and attaching any required official court forms.