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Child Support Lawyer in Chicago
What Illinois guidelines actually require, and how to make sure the number reflects your real finances.
Child Support Isn't Just a Number. It's Your Child's Standard of Living.
When a marriage or relationship ends, both parents remain financially responsible for their children. Illinois law is clear on that point. What's less clear — and what often becomes a significant source of conflict — is how that obligation is calculated, what it covers, and what happens when circumstances change.
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Child support disputes are among the most common matters we handle. Whether you're establishing support for the first time, dealing with a spouse who isn't paying, or facing a request to modify an existing order, the outcome has real consequences for your child and for your finances.
How Illinois Calculates Child Support
Illinois uses an income shares model for child support. Rather than basing support solely on the paying parent's income, the income shares model considers both parents' incomes and attempts to approximate the amount the child would have received if the family had remained intact.
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The calculation starts with both parents' net incomes — gross income minus certain allowable deductions including taxes, Social Security, mandatory retirement contributions, and prior child support obligations. Those net incomes are combined and applied to a schedule that produces a basic support obligation based on the number of children. That obligation is then allocated between the parents proportionally based on each parent's share of the combined income.
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Parenting time also affects the calculation. When a parent has 146 or more overnights with the child per year — a shared parenting arrangement — a parenting time adjustment reduces that parent's support obligation to reflect the direct costs they're already incurring.
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The formula produces a presumed amount. Courts can deviate from it when the result would be inequitable given the specific circumstances of the case.
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Here is what that looks like with round numbers. Parent A nets $6,000 a month and Parent B nets $3,000, they have one child, and the child lives mainly with Parent B. Combined net income is $9,000, and Parent A earns two-thirds of it. The 2026 HFS schedule sets the basic support obligation for one child at that income level at $1,585 a month, so Parent A’s guideline payment is two-thirds of that, about $1,057 a month, before health insurance and other add-ons are allocated. Change the incomes, the number of children, or the overnight split and the result moves.
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You can run your own numbers on our Illinois child support calculator. It uses the current HFS schedule and takes about a minute.
What Changes on January 1, 2027
Illinois rewrote part of the child support statute in 2026. Public Act 104-0733 (Senate Bill 3524), signed July 31, 2026, amends 750 ILCS 5/505 and 5/510 and takes effect January 1, 2027. If you are calculating support now or expect to be back in court next year, the differences matter.
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The shared-parenting threshold drops from 146 overnights a year to 110. The shared-care formula still starts at 150 percent of the basic support obligation and allocates it by each parent’s income share and the other parent’s parenting-time percentage. A parent with 110 to 145 overnights no longer gets the full shared-care calculation or nothing; instead the guideline amount is adjusted on a sliding scale, 10 percent at 110 to 114 overnights down to 2 percent at 140 to 145, and the adjusted figure can never exceed what the basic guidelines would produce. Courts can also recognize “overnight equivalents,” meaning significant parenting periods on separate days where the child is in a parent’s direct care but does not stay the night, either by agreement or as a guideline deviation.
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Other changes: the income level at which the $40-per-child presumptive minimum applies moves from 75 percent to 100 percent of the federal poverty guidelines; a parent incarcerated for more than 180 consecutive days is presumed unable to pay; parents will exchange written proof of net income each year and report a new job or a job loss within 10 days; and HFS must publish new worksheets for the revised math.
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Nothing changes automatically. An order entered under the current rules stays in place until someone asks the court to modify it. If your parenting schedule puts you between 110 and 145 overnights, the new law itself may be the substantial change that supports a modification petition. Our post on the 2027 child support changes walks through the details.
Establishing Child Support for the First Time
Child support can be established as part of a divorce proceeding or, for parents who were never married, through a separate parentage action. In either case the process involves financial disclosure from both parties, calculation under the Illinois guidelines, and entry of a court order. For parents who were never married, parentage has to be established first, by a signed Voluntary Acknowledgment of Paternity or a court finding, before support can be ordered.
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An agreed support order — one both parents have negotiated and signed — is faster and less expensive than a litigated one. It also gives the parties more flexibility to address specific expenses and circumstances that a standard judicial order might not capture. We help clients reach support agreements that are fair, complete, and enforceable.
What Child Support Covers and What It Doesn't
The basic child support obligation is intended to cover ordinary day-to-day expenses — housing, food, clothing, and routine costs of raising a child. It does not automatically cover everything.
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Illinois law separately addresses two categories of additional expenses:
Healthcare
One or both parents may be ordered to maintain health insurance for the child. Uninsured or unreimbursed medical expenses — co-pays, deductibles, orthodontia, therapy, and other costs not covered by insurance — are typically allocated between the parents in proportion to their incomes. The agreement or order needs to address this specifically.
Extracurricular and Educational Expenses
Costs like school tuition, tutoring, sports, music lessons, and similar activities are not automatically included in base support. Courts can order these expenses to be shared, and a well-drafted support order addresses them directly rather than leaving them to future dispute.
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These additional expenses are a significant source of post-divorce conflict when they're not addressed clearly from the start. We make sure they are.
Income: The Most Contested Part of the Calculation
The child support formula is only as reliable as the income figures going into it. In cases involving salaried employees with straightforward W-2 income, this is relatively simple. In cases involving self-employed parents, business owners, cash income, variable compensation, or intentional underemployment, income determination becomes the central dispute.
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Illinois courts have tools to address income that isn't what it appears to be. Courts can impute income to a parent who is voluntarily unemployed or underemployed — attributing what they could be earning based on their education, work history, and the job market — rather than accepting artificially low reported income. Discovery tools including tax returns, bank statements, business records, and depositions help build the complete picture.
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If you believe your co-parent is understating their income, that's a fight worth having. The difference compounds over years of payments.
When Circumstances Change
Child support orders are not permanent. They can be modified when there has been a substantial change in circumstances since the last order was entered.
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Common grounds for modification include a significant increase or decrease in either parent's income, job loss or a new higher-paying position, a change in the child's financial needs, a change in the parenting time arrangement, or the child aging out of coverage for certain expenses. Beginning in 2027, a parenting schedule of 110 to 145 overnights, which had no effect on support under the old 146-night rule, may itself support a modification. Our Post-Decree Modifications page covers the process.
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In cases enforced through Illinois Healthcare and Family Services (HFS), Illinois also provides a three-year review mechanism — either parent can request a review of the support order every three years without having to prove a substantial change in circumstances. If the recalculated amount differs from the current order by at least twenty percent, the court can modify it.
College Expenses After 18 (Section 513)
Child support in Illinois normally ends at 18, or at 19 if the child is still in high school, but that is not the end of a parent’s potential obligation. Under Section 513 of the Illinois Marriage and Dissolution of Marriage Act, a court can order either or both parents to contribute to a child’s college or vocational-school costs, including tuition, fees, housing, books, medical expenses, and living expenses.
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There are limits. Tuition and fees are capped at the in-state cost at the University of Illinois at Urbana-Champaign, and housing at the cost of a double room with a standard meal plan there, unless the parties agree otherwise. The expenses have to be incurred before the child turns 23, or 25 with good cause. The obligation ends if the child fails to maintain a cumulative C average, turns 23, earns a bachelor’s degree, or marries. The court looks at both parents’ finances, the standard of living the child would have had if the marriage had continued, the child’s own resources, including college savings accounts, and the child’s academic performance.
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Two practical points. A 513 award is retroactive only to the date the petition is filed, so a parent who waits until sophomore year to ask has already lost freshman year. And the issue is far easier to handle in the divorce judgment, even if the child is young, than to litigate later when the tuition bill is due.
Enforcement: When Support Isn’t Being Paid
A child support order is a court order. Failing to pay it has consequences, and those consequences can be significant.
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Illinois has robust enforcement mechanisms for unpaid child support. These include income withholding orders that direct an employer to deduct support directly from the paying parent’s paycheck, liens on real property and bank accounts, suspension of driver’s and professional licenses, interception of tax refunds, and findings of contempt of court that can result in fines or jail time. In most cases, payments run through the Illinois State Disbursement Unit by income withholding from the start, which creates a payment record that makes arrears easy to prove.
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If your co-parent is not paying court-ordered support, you have options. We move quickly on enforcement matters and pursue the remedies most likely to produce results in your specific situation.
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Unpaid support accrues as a judgment. The other parent cannot simply walk away from arrears by later claiming hardship. They owe what the order required, with interest, until it is paid.
Child Support Cases in Cook, DuPage, and Will Counties
In Cook County, child support in a divorce is handled by the Domestic Relations Division, mainly at the Daley Center downtown, with suburban districts hearing some cases. Support between unmarried parents runs through the parentage calendar. Cases where the State is involved, because a parent receives public benefits or has applied for HFS enforcement services, are handled with the State’s Attorney’s child support enforcement attorneys, which changes the pace and the players. Every support case starts with a sworn Financial Affidavit and the supporting documents behind it, and the judges expect it to be complete.
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DuPage County support cases are heard at the courthouse in Wheaton. The Financial Affidavit requirements are the same, the calendars tend to move faster than Cook’s, and agreed orders can often be entered without a contested hearing.
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Will County cases are heard in Joliet. The process is the same in substance, with local rules on scheduling and pretrial procedure. Our attorneys appear regularly in all three counties and know how each courthouse handles support disputes, from a first-time order to a contempt petition.
Do You Need a Lawyer for Child Support in Illinois?
Not always, and we will tell you if you don’t. When both parents are W-2 employees, the parenting schedule is settled, and you agree on the number the guidelines produce, an agreed order can often be handled with limited help, and HFS offers free establishment and enforcement services for parents who qualify.
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A lawyer earns their fee when the inputs are in dispute. That means a parent who is self-employed, paid in cash, or running income through a business; a claim that the other parent is underemployed on purpose; arrears that have built up over years; a parent who has moved out of state; a co-parent who will not turn over financial records; or a parenting schedule near the 110-overnight line where the 2027 rules change the math. In those cases the difference between the right number and the convenient number compounds for years.
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If you are not sure which category you are in, a consultation will tell you. We will say plainly whether your case needs us.
Our Approach to Child Support
Why Clients Choose LaRocque Law
Child support cases look simple until they aren't. The formula is clear — the inputs often aren't. We know how to identify income that isn't being disclosed, how to challenge imputation arguments, how to enforce orders that aren't being followed, and how to modify support when life changes in ways the original order didn't anticipate.
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We represent both parents seeking support and parents paying it. Our job is to make sure the number is right — calculated correctly, documented thoroughly, and enforceable when it needs to be.
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LaRocque Law serves clients in Cook County, DuPage County, and Will County.
"Her response time and attention to detail are exceptional. She encourages me and keeps me focused. She never hesitates to give sound advice on the spot." — Kate, client. Past results and client testimonials do not guarantee future outcomes; every case is unique.
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Cases are handled by Rebecca LaRocque and Tyler Keller. Family law only, in Cook, DuPage, and Will Counties.
Frequently asked questions
How is child support calculated in Illinois?
Illinois uses an income shares model that considers both parents' net incomes. The combined income is applied to a statutory schedule to determine a basic support obligation, which is then divided proportionally between the parents based on each parent's share of that combined income. Parenting time also affects the calculation. Parents with 146 or more overnights per year receive a parenting time adjustment that reduces their support obligation to reflect the direct costs they're already incurring.
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What counts as income for child support purposes?
Illinois law defines income broadly. It includes wages, salary, tips, commissions, bonuses, self-employment income, rental income, investment income, pension and retirement benefits, unemployment compensation, workers' compensation, and income from any other source. Courts can also impute income to a parent who is voluntarily unemployed or working below their earning capacity based on their education, work history, and the available job market.
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Can child support be waived by agreement?
No. Child support belongs to the child, not the parent. Parents cannot waive or contract away a child's right to financial support from both parents. They can agree on an amount, and courts will generally approve agreed support orders, but they cannot agree to zero support for a child who has financial needs that both parents are obligated to meet.
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What can you do if the other parent stops paying support?
A child support order is enforceable. If the other parent does not pay, you can ask the court to use income withholding, liens, tax refund interception, license suspension, or contempt remedies. Unpaid support becomes arrears and continues to be collectible. We can help you choose the right enforcement path for your case.
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What is the State Disbursement Unit?
The Illinois State Disbursement Unit, commonly called the SDU, is the centralized payment processing center through which most child support payments in Illinois are routed. Rather than paying the other parent directly, the paying parent sends payments to the SDU, which then distributes them to the receiving parent. The SDU also maintains a record of all payments made and received, which becomes important if there is ever a dispute about arrears or compliance.
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Do all child support payments have to go through the SDU?
In most cases, yes. When an income withholding order is in place, payments are automatically routed through the SDU. Even when payments are made voluntarily, without an active income withholding order, Illinois courts typically require that they go through the SDU so there is an official record. Direct payments between parents, while not impossible, create significant risk for the paying parent because they are harder to document and may not be credited properly if a dispute arises.
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What is an income withholding order?
An income withholding order, sometimes called an IWO, is a court order that directs an employer to deduct child support payments directly from the paying parent's paycheck and send them to the SDU. Income withholding is the default method of collection in Illinois child support cases. It takes the obligation out of the paying parent's hands and makes compliance automatic, which reduces the risk of missed or late payments.
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How does income withholding work in practice?
Once an income withholding order is entered, it is sent directly to the paying parent's employer. The employer is required by law to begin withholding within a set number of business days and to remit the withheld amount to the SDU on a regular schedule. The SDU then processes the payment and distributes it to the receiving parent. From the receiving parent's perspective, support arrives through the SDU rather than directly from the other parent.
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What happens if my employer doesn't comply with an income withholding order?
Employers are legally obligated to comply with income withholding orders. An employer who fails to withhold as required can be held liable for the amounts that should have been withheld. If you are the receiving parent and payments are not arriving, or if you are the paying parent and your employer has not implemented the withholding, contact us. Non-compliant employers can be compelled to comply and held responsible for their failure to do so.
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What percentage of income is child support in Illinois?
Illinois eliminated the old flat-percentage system (20% for one child, 28% for two, and so on) in 2017. If you're seeing those numbers online, they're outdated. Today's amount depends on both parents' incomes and the parenting schedule, not a fixed percentage of one parent's paycheck.
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When does child support end in Illinois?
Child support ends when the child turns 18, or when they graduate high school if that is later, up to age 19. It does not always stop automatically; whether it terminates on its own depends on how the order is written, so check your order before assuming payments can just stop. Support for a child with a disability, and contributions to college expenses, can extend beyond that.
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Do parents have to pay for college in Illinois?
Illinois is one of the states where a court can order divorced or unmarried parents to contribute to a child's college expenses, including tuition, housing, and related costs, based on both parents' resources. This is separate from regular child support and has its own rules under 750 ILCS 5/513, including caps tied to in-state public university costs and a requirement that the child maintain a C average. If college is on the horizon, it is worth addressing in the judgment rather than leaving it for later.
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How do I file for child support in Illinois?
There are two main routes: through the state (HFS, the child support services agency) at low cost, or through a private case filed in court by your attorney. The state route is cheaper but slower and handles only support. A private filing can address support alongside parenting time and other issues, and typically moves faster. Which makes sense depends on your situation.
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Can child support be stopped or canceled in Illinois?
Not by the parents on their own. Child support belongs to the child, so even if both parents agree to end or reduce it, the change isn't effective until a court approves it. If circumstances have changed, for example the child now lives with you, the other parent's income changed, or the child aged out, the remedy is a court order terminating or modifying support, not an informal agreement.
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How do I change the amount of child support?
Either parent can seek a modification when there's been a substantial change in circumstances, such as a job loss, a significant income change, or a change in the parenting schedule. Two things matter. Modifications generally only reach back to the date the request was filed, not the date circumstances changed, so waiting costs money. And until a new order is entered, the existing amount remains fully enforceable.
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What does child support cover — and what doesn't it?
Basic support covers the child's ordinary living expenses: housing, food, clothing, and everyday costs. On top of the basic amount, courts routinely order the parents to share additional expenses, including health insurance premiums, uncovered medical costs, childcare, and sometimes extracurricular activities and school expenses. If your order doesn't address these add-ons, it may be worth revisiting.
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Does 50/50 parenting time mean no child support?
Not necessarily. When each parent has at least 146 overnights a year, Illinois applies a shared-care formula that usually reduces support, but if the parents' incomes differ, the higher earner typically still pays something. Equal time with equal incomes can approach zero, but it isn't automatic.
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Does the 2027 child support law change my existing order?
No. Public Act 104-0733 takes effect January 1, 2027, but it does not rewrite orders that are already entered. Your current order stays in place until a court modifies it. What the new law does is give some parents a reason to ask: if you have between 110 and 145 overnights a year, the new graduated shared-care adjustment may produce a different number than your order, and that change in the law can support a petition to modify.
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How much does a child support lawyer cost in Chicago?
Most family law attorneys, including our firm, bill hourly against a retainer, and the total depends on how much is actually in dispute. An agreed order with straightforward W-2 incomes costs a fraction of a case that requires discovery into a business, an imputation hearing, or a contempt petition over arrears. We give a candid estimate at the consultation once we know which kind of case you have, and we will tell you if your case does not need a lawyer.