Illinois Child Support Office
Updated August 2026
Illinois' Division of Child Support Services, part of the Department of Healthcare and Family Services (HFS), runs child support statewide with a separate mailing address for Cook County cases.
Phone
800-447-4278Official Website
Official Site ↗Mailing Address
Department of Healthcare and Family Services – Division of Child Support Services
Division of Child Support Services, Client Services Unit, P.O. Box 19405
Springfield, IL 62794-9405
Case Account
Manage Your Case ↗Payments
Make a Payment ↗About the Department of Healthcare and Family Services – Division of Child Support Services
Illinois runs child support through HFS, its health and family services agency, rather than a separate child support department. It's administered at the state level, with Cook County cases routed to a distinct mailing address from the rest of the state.
The division locates noncustodial parents, establishes paternity, sets support orders, and collects and enforces payments once a case is active, with case management available through the HFS online portal.
Illinois uses the Income Shares model to calculate support. See how this compares to other states →
Illinois's default child support termination age is 18. See the full rules, including high school and disability extensions →
Circumstances change — see how to request a modification in Illinois →
How to Apply for Child Support in Illinois
A parent or caretaker of a child can apply for Illinois child support services through the HFS online portal. Families already receiving TANF or Medicaid in Illinois are typically referred for services automatically.
The application requires identifying information for both parents and the child, along with any existing custody or support paperwork. The division then works to establish paternity if needed and get a support order in place.
How to Collect Child Support Payments in Illinois
Illinois collects most support through income withholding once an order is active, processed through the Illinois State Disbursement Unit and paid out to the receiving parent by direct deposit or debit card.
The SDU has its own customer service line, 877-225-7077, separate from the main HFS number, for payment- and disbursement-specific questions.
Missed Payments & Enforcement
Illinois can intercept tax refunds, suspend licenses, and report arrears to credit bureaus when a parent falls behind on payments, coordinated through HFS.
As in every state, federal law allows a passport to be denied or revoked once past-due support exceeds $2,500.
Frequently Asked Questions
How do I apply for Illinois child support services? +
Through the online portal at online.hfs.illinois.gov. Families already receiving TANF or Medicaid in Illinois are typically referred for services automatically.
Does Cook County have a different mailing address for child support? +
Yes — Cook County cases mail to a separate P.O. Box in Chicago, while all other Illinois counties use the Springfield Client Services Unit address.
Who do I contact about a payment I haven’t received? +
The Illinois State Disbursement Unit handles payment- and disbursement-specific questions at 877-225-7077, separate from the general HFS child support line.
Helpful Resources
Calculator & Guidelines
See how Illinois calculates the current amount, and how it compares to other states.
Learn more →When Support Ends
Illinois's default termination age, plus how high school, disability, or college can extend it.
Learn more →Modify an Order
What counts as a substantial change and how to request a modification in Illinois.
Learn more →Interstate Cases
How UIFSA determines jurisdiction when the other parent lives outside Illinois.
Learn more →This page is your Illinois starting point
Contact information above covers what the Department of Healthcare and Family Services – Division of Child Support Services handles directly, but the guideline model, termination age, and modification rules that decide your amount live on the dedicated pages linked here. And if the other parent lives outside Illinois, interstate rules — not Illinois's own procedures — determine which state has authority.
Nearby State Child Support Offices
Rules, portals, and enforcement tools change at the state line. If a case involves parents in more than one state, start with each state's own office — interstate cases are handled through direct cooperation between the agencies involved.