Illinois Child Support Calculator (2026)
Estimate your child support payments in Illinois using our free calculator based on the official 750 ILCS 5/505 (Illinois Marriage and Dissolution of Marriage Act). Enter your income details below to get an instant estimate.
Illinois Child Support Calculator
Based on Illinois's 2024 750 ILCS 5/505 (Illinois Marriage and Dissolution of Marriage Act)
This is an estimate only. See our full disclaimer.
Key Facts: Child Support in Illinois
- Illinois uses the Income Shares model (since July 1, 2017), basing child support on both parents' combined monthly net incomes.
- Net income is calculated using standardized tax deduction tables rather than actual tax returns.
- The basic obligation for 1 child ranges from approximately $184/month at $1,000 combined income to $2,440/month at $30,000 combined monthly net income.
- A shared parenting adjustment applies when the non-custodial parent has 146 or more overnights per year (40% of the time).
- The self-support reserve is 75% of the federal poverty level, approximately $934 per month.
Source: 750 ILCS 5/505 (Illinois Marriage and Dissolution of Marriage Act) • Last verified: 2026-05-30
How Much Is Child Support in Illinois?
If you make $60,000 a year in Illinois, child support for 1 child is estimated at $731 per month ($8,772 per year) based on the 750 ILCS 5/505 (Illinois Marriage and Dissolution of Marriage Act). This assumes the other parent earns approximately $36,000/year. Actual amounts depend on both parents' incomes, custody arrangements, and additional expenses.
If you make $1,000 a week ($52,000/year) in Illinois, child support for 1 child is approximately $664/month.
Illinois Child Support Estimates by Income (2026)
| Annual Income | 1 Child | 2 Children | 3 Children |
|---|---|---|---|
| $40,000/yr | $553/mo | $816/mo | $981/mo |
| $50,000/yr | $646/mo | $954/mo | $1,147/mo |
| $60,000/yr | $731/mo | $1,078/mo | $1,297/mo |
| $70,000/yr | $807/mo | $1,191/mo | $1,432/mo |
| $80,000/yr | $877/mo | $1,294/mo | $1,556/mo |
| $100,000/yr | $1,001/mo | $1,476/mo | $1,776/mo |
| $120,000/yr | $1,107/mo | $1,634/mo | $1,966/mo |
Estimates assume the other parent earns 60% of your income. Actual amounts vary based on both parents' incomes, custody time, and adjustments. Compare all states →
How Child Support Is Calculated in Illinois
Illinois uses the Income Shares model to calculate child support obligations. This model combines both parents' incomes to determine the total child support obligation, then divides it proportionally based on each parent's share of the combined income.
Factors That Affect Child Support in Illinois
Important Notes for Illinois
- Illinois switched from the Percentage of Income model to the Income Shares model effective July 1, 2017.
- Child support is based on both parents' combined monthly net incomes using standardized tax deduction tables.
- Net income is calculated using a standardized tax chart rather than actual taxes, ensuring consistency.
- Illinois provides a shared parenting time adjustment when the non-custodial parent has 146 or more overnights per year (40%).
Example Child Support Calculation in Illinois
Scenario: Parent A earns $5,000/month, Parent B earns $3,000/month, 2 children.
Step 1: Combined monthly income: $5,000 + $3,000 = $8,000
Step 2: Parent A's income share: $5,000 / $8,000 = 62.5%
Step 3: Look up basic obligation from the guidelines schedule for $8,000 combined income and 2 children.
Step 4: Multiply the basic obligation by Parent A's share (62.5%) to determine their payment.
Note: Additional adjustments for health insurance, child care, and parenting time may apply.
Frequently Asked Questions About Illinois Child Support
How is child support calculated in Illinois?
How much is child support in Illinois?
How is net income calculated for Illinois child support?
Does shared parenting reduce child support in Illinois?
About This Calculator
This calculator uses the official 750 ILCS 5/505 (Illinois Marriage and Dissolution of Marriage Act) (2024 guidelines) to estimate child support in Illinois. Calculations were last verified against the official source on 2026-05-30.
Disclaimer: This calculator provides estimates only and does not constitute legal advice. Actual child support amounts are determined by Illinois courts and may differ based on factors not included here. For legal advice, consult a Illinois family law attorney.
Our methodology: Based on the Income Shares model as defined in the 750 ILCS 5/505 (Illinois Marriage and Dissolution of Marriage Act). Updated for 2026.