Child support on $150,000 a year in Illinois (4 children)
Illinois guidelines effective March 20, 2026. Illinois overview
If Parent A earns $150,000 a year, Parent B earns $40,000 and the children live mostly with Parent B (52 overnights a year with Parent A), Illinois's guideline amount is $2,690 a month (Parent A pays Parent B).
Across the table below it ranges from $546 (Parent B earns $100,000, equal time) to $3,031 (Parent B has no income, Parent A has no overnights).
This is the guideline amount, not a court order.
Change the numbers
Guideline child support
Illinois · 4 children · Parent A $150000 per year · Parent B $40000 per year · children live mostly with Parent B
$2,690 a month
Parent A pays Parent B
- Parent A: 76.3% of combined income
- Parent B: 23.7%
How it adds up
- Combined income
- $11,522 a month
- Basic obligation
- $3,526 a month
- Parent A's share of income
- 76.3%
- Guideline amount
- $2,690 a month
See the worksheet for this example
- Illinois's guidelines change on January 1, 2027. Switch versions above to compare.
Illinois uses the income shares model under 750 ILCS 5/505. Official calculator: cscwebext.hfs.illinois.gov. Child support agency: Illinois Department of Healthcare and Family Services, Child Support Services.
Estimate under Illinois's child support guidelines effective March 20, 2026. Verified against the official Illinois sources on October 6, 2026. Not legal advice. Courts can deviate from the guidelines. How we calculate →
By parenting time and the other parent's income
| Overnights | $0 | $20,000 | $30,000 | $40,000 | $50,000 | $60,000 | $80,000 | $100,000 |
|---|---|---|---|---|---|---|---|---|
| 0 | $3,031 A→B | $2,860 A→B | $2,784 A→B | $2,690 A→B | $2,605 A→B | $2,588 A→B | $2,569 A→B | $2,489 A→B |
| 52 | $3,031 A→B | $2,860 A→B | $2,784 A→B | $2,690 A→B | $2,605 A→B | $2,588 A→B | $2,569 A→B | $2,489 A→B |
| 104 | $3,031 A→B | $2,860 A→B | $2,784 A→B | $2,690 A→B | $2,605 A→B | $2,588 A→B | $2,569 A→B | $2,489 A→B |
| 128 | $3,031 A→B | $2,860 A→B | $2,784 A→B | $2,690 A→B | $2,605 A→B | $2,588 A→B | $2,569 A→B | $2,489 A→B |
| 182 | $2,273 A→B | $1,795 A→B | $1,591 A→B | $1,390 A→B | $1,212 A→B | $1,063 A→B | $807 A→B | $546 A→B |
The Illinois worksheet for this example
| Line | Official label | Value |
|---|---|---|
| 1 | Gross Monthly Income (Parent A)Parent A's gross monthly income | $12,500.00 a month |
| 2 | Standardized Net Income (Parent A)Parent A's standardized net income | $8,790.00 a month |
| 2 | Standardized Net Income (Parent B)Parent B's standardized net income | $2,732.00 a month |
| 8C | Adjusted Net Income (Combined)Combined adjusted net income | $11,522.00 a month |
| 9 | Each Parent's Percentage Share (Parent A)Parent A's share | 76.29% |
| 10 | Basic Child Support ObligationSchedule amount | $3,526.00 a month |
| 11 | Each Parent's Contribution (Parent A)Parent A's share of the schedule amount | $2,689.99 a month |
| — | Child Support ObligationGuideline amount | $2,689.99 a month |
With child care and health insurance
Illinois's guideline amount doesn't add child care costs.
| Costs | Guideline amount |
|---|---|
| No add-ons | $2,690 a month A→B |
| Child care $500 a month | $2,690 a month A→B |
| Child care $1,000 a month | $2,690 a month A→B |
| Health insurance $150 a month | $2,804 a month A→B |
| Health insurance $300 a month | $2,919 a month A→B |
The children's health insurance premium is shared by net income. Child care and school costs are ordered separately at the court's discretion.
Things to know about this example
- Illinois's guidelines change on January 1, 2027. Switch versions above to compare.
How Illinois works it out
Illinois uses the income shares model: the schedule gives the support for the parents' combined net income, and the paying parent pays their percentage share.
Net income comes from the state's standardized gross-to-net table, which differs for the parent with most of the parenting time. Support paid for other children is then deducted.
When each parent has at least 146 overnights a year, the basic obligation is multiplied by one and a half, shared by income and offset by each parent's time.
Frequently asked questions
How much child support is paid on $150,000 in Illinois for 4 children?
If Parent A earns $150,000 a year, Parent B earns $40,000 and the children live mostly with Parent B (52 overnights a year with Parent A), Illinois's guideline amount is about $2,690 a month (Parent A pays Parent B).
How much is that a week?
That is about $621 a week (the monthly amount × 12 ÷ 52).
What if the parents share time equally?
With about equal parenting time and the same incomes, the guideline amount is about $1,390 a month (Parent A pays Parent B).
What if Parent B has no income?
If Parent B has no income and the children live mostly with Parent B, the guideline amount is about $3,031 a month (Parent A pays Parent B).
Official sources and verification
- Law: 750 ILCS 5/505
- Illinois child support guidelines
- Support Obligation Worksheet (HFS)
- Official Illinois child support calculator
- Illinois Department of Healthcare and Family Services, Child Support Services
- Changing a Illinois child support order
Guidelines effective March 20, 2026. Verified against the official Illinois sources on October 6, 2026. How we calculate →