Official online calculator tool from HFS to estimate child support obligations based on the Illinois income shares model. This free tool helps both parents and attorneys project support amounts before going to court. Enter both parents' incomes, parenting time allocation, and number of children to get an estimate. Useful for fathers preparing for hearings, negotiating settlements, or requesting modifications based on income changes.
Child support in the United States is administered state-by-state under the Title IV-D federal program, with every state required to operate a child support enforcement agency. These agencies establish paternity, locate non-custodial parents, calculate support obligations, and enforce payments through wage garnishment, tax refund intercepts, license suspension, and other civil enforcement tools. Support amounts are calculated using state-specific guidelines, most based on an income shares or percentage-of-income formula. Fathers paying support can request modifications when their income drops substantially or when circumstances change (job loss, additional children, disability). Fathers owed support can open a case with their state agency free of charge. This directory includes each state's child support agency, online calculators, local enforcement offices, and modification resources.
Child Support in Illinois
Illinois handles family law through circuit courts in each of its 23 judicial circuits, with Cook County running its own Domestic Relations Division. The Division of Child Support Services handles enforcement. Chicago dominates the state; downstate metros include Aurora, Rockford, Joliet, Naperville, and Peoria. Legal Aid Chicago (formerly CVLS) and Land of Lincoln Legal Aid cover most of the state for low-income fathers.
Illinois State Disbursement Unit (SDU) — Central payment processing center handling all Illinois child support payments from employers and individual payers for distribution to cust
Illinois HFS Child Support Customer Portal — Online portal where parents can view child support case details, payment history, and submit requests for modifications. Available 24/7, thi
Child Support — Common Questions
How do I open a child support case?
Apply through your state's Child Support Services agency — usually online, in person, or by mail. Applications are free, and the agency handles paternity establishment, order creation, and enforcement on your behalf. You don't need the other parent's cooperation to open a case.
Can I modify my child support order?
Yes, if there's a substantial change in circumstances (income drop of 15–25% or more, job loss, disability, a new child, change in custody time). File a Motion to Modify with the court that issued the original order. Most states don't modify retroactively — file as soon as circumstances change.
What happens if I can't pay?
Contact the child support agency immediately — don't ignore the debt. Options include payment plans, hardship modifications, and in some states, work programs that substitute community service for payment. Accumulated arrears don't disappear but can sometimes be reduced through debt compromise programs.
How is the amount calculated?
Each state uses guidelines — most follow Income Shares (combining both parents' income) or Percentage of Income (only non-custodial parent's income). Online calculators on every state agency site estimate your obligation. The actual order also considers health insurance, childcare, and other add-ons.