Financial child support is essential to a child’s stability. Some parents can agree to reasonable support for their children, but sometimes, child support is an adversarial issue.

Jump to the Illinois Child Support Calculator

You may have to fight for what’s right for your child, but where should you start?

You do not have to figure out the details of Illinois child support laws on your own. If you have questions about child support, the Vantage Group Legal Services can help.

Our subscription service offers affordable representation on family law matters, including child support. Our in-network attorneys are experienced and can help you get the support you need. 


What Are the New Child Support Laws in Illinois as of 2022?

The new child support laws in Illinois in 2022 require that the parents purchase or maintain health insurance for the child or children when dealing with a child support matter. This mandate is in effect whenever the parents deal with child support, such as a part of a divorce or a child custody case. The insurance can be public or private, such as through an employer-sponsored program. 


Illinois Child Support Calculator

Disclaimer: This Child Support is provided solely for informational purposes and does not constitute legal advice or a legal opinion of any kind. The results obtained through the calculator are strictly informative and do not guarantee or predict any judicial decision. The accuracy of the calculator is not certified or warranted by Vantage Group Legal Services. We strongly advise that you seek the advice of a qualified attorney before making any decisions regarding divorce, separation, custody, or support and before signing any related legal documents that may affect your legal rights.

How to use the Calculator

  1. First, enter the number of children that you and your partner share.
  2. Next, enter the gross (after taxes) income of the custodial parent (ie. the parent who has majority physical custody)
  3. Next, enter the gross income of the non-custodial parent.
  4. Finally, click the Calculate button. The figure labeled Total Child Support Obligation is the total amount of child support due based on the Illinois Income Shares model.
  5. The figures for the Custodial and Non-custodial parents represent the estimated amount each parent will owe. This is determined by multiplying each parent’s percentage of the total gross income by the total child support obligation.

Important Notes

  • This calculator provides an estimate based on the Standard Child Support Calculation. It does not provide an estimate for Shared Parenting Child Support Calculation. You can read more about the distinction between these below under the heading “How Is Child Support Calculated in Illinois?”.
  • This calculator references the Illinois Income Shares Model to determine the total child support obligation based on the number of children and combined net income of the parents.
  • The calculator then multiples the total support obligation by the percentage share of income from each parent, which gives the estimated amount owed by each parent.

How Is Child Support Calculated in Illinois?

As of 2017, the Illinois child support laws use what is known as an Income Shares Model. Most states in the U.S. use the Income Shares Model to calculate child support. The income shares model estimates what the household income would be if the parents resided together. Thus, both parents’ incomes are taken into account.

Essentially, the income shares model calculates child support by:

  • Determining each parent’s net income;
  • Combining the two net incomes to figure out the combined net income (i.e., what the household income would be if the parents resided together);
  • Determining each parent’s percentage of the household income;
  • Finding the combined net income and number of shared children on the income shares chart to determine the child support cost; and
  • Multiplying that number by the parent’s percentage of the child support obligation.

An easy way to estimate the child support obligation without calculating all of this on your own is through a Child Support Calculator available on the Illinois Department of Healthcare and Family Services’ website.

The custodial parent is assumed to fulfill the child support obligation because the child lives with them. However, the Illinois Department of Healthcare and Family Services has a worksheet to help determine if one parent has to pay another parent-child support when there is joint custody.  

Standard Child Support Calculation in Illinois

The following formula applies when one of the parties exercises less than 146 days of parenting time per year.

Step One: Determine Your Adjusted Net Income

Adjusted net income is generally gross income minus taxes and other permissible deductions. If Father earns $8,000 per month and pays $2,000 per month in taxes, his adjusted net income would be $6,000. 

Step Two: Determine Your Combined Adjusted Net Income

Combined adjusted net income is determined by adding each parent’s adjusted net income together. For example, if Father nets $6,000 per month, and Mother nets $5,000 per month, then the parties’ combined adjusted net income would be $11,000 per month. 

 Step Three: Determine the Total Child Support Obligation

The Illinois Income Shares Schedule is used to determine how much financial support a child is entitled to. The schedule is meant to approximate how much support the child would have received if the parents were married and living together. To determine one’s total support obligation, look for the parent’s combined net income on the left-hand side of the schedule and match it to the number of minor children listed at the top.

For example, Mother and Father have three children and a combined adjusted net income of $11,000 per month. Pursuant to the Illinois Income Shares Schedule, the total child support obligation for three children is $2,755 per month. 

Step Four: Determine Each Parent’s Share of the Total Child Support Obligation

For this step, divide a parent’s respective monthly net income (From Step 1) by the parents’ combined net income (From Step 2), then multiply the answer by the total child support obligation amount (From Step 3). 

For example, if Father nets $6,000 per month, and Mother nets $5,000 per month, the parents combined net income is $11,000 per month. $6,000 divided by $11,000 is 55%. 55% multiplied by $2,755 comes to $1,503 per month for Father. 

Use the same calculation for Mother. $5,000 per month divided by $11,000 is 45%. 45% multiplied by $2,755 comes to $1,252 per month for Mother. 

Step Five: The Non-Custodial Parent Pays Their Entire Share to the Custodial Parent

If the children reside primarily with Father, Mother must pay him all her share ($1,252 per month). Because Father is the custodial or primary residential parent, Illinois courts will presume that he is properly contributing his own share ($1,503 per month) toward necessities for the children.

Shared Parenting Child Support Calculation in Illinois

Illinois courts calculate child support differently when each parent exercises at least 146 days (overnights) or 40% of parenting time with the child. Generally, child support calculated pursuant to a shared parenting time schedule will yield a much lower child support obligation for the noncustodial parent. 

Step One: Determine Your Adjusted Net Income

Adjusted net income is generally gross income minus taxes and other permissible deductions. If Father earns $8,000 per month and pays $2,000 per month in taxes, his adjusted net income would be $6,000. 

Step Two: Determine Your Combined Adjusted Net Income

Combined adjusted net income is determined by adding each parent’s adjusted net income together. For example, if Father nets $6,000 per month, and Mother nets $5,000 per month, then the parties’ combined adjusted net income would be $11,000 per month. 

Step Three: Determine the Total Child Support Obligation

Illinois courts increase the total child support obligation for shared parenting arrangements. To determine the total support obligation, look for the parents’ combined net income on the left-hand side of the income shares schedule and match it to the number of minor children listed at the top. Next, multiply that amount by 150%.

For example, Mother and Father have three children and a combined adjusted net income of $11,000 per month. Pursuant to the Illinois Income Shares Schedule, the child support obligation for three children is $2,755 per month. $2,755 multiplied by 150% is $4,132.50. $4,132.50 is the total child support obligation.

Step Four: Determine Each Parent’s Share of the Total Child Support Obligation

For this step, divide a parent’s respective monthly net income (from Step 1) by both parents’ combined net income (from Step 2), then multiply the answer by the total child support obligation amount (from Step 3). Now, multiply that answer by the other parent’s percentage of parenting time out of the year. In this scenario, we will assume that the parents share parenting time 50/50.

If Father nets $6,000 per month, and Mother nets $5,000 per month, the parents’ combined net income is $11,000 per month. $6,000 divided by $11,000 is 55%. 55% multiplied by $4,132.50 comes to $2,272.88. $2,272.88 multiplied by 50% parenting time comes to $1,136.44.

For Mother, $5,000 per month divided by $11,000 is 45%. 45% multiplied by $4,132.50 comes to $1,859.63. $1,859.63 multiplied by 50% parenting time comes to $929.82.

Step Five: Offset the Difference 

Even though Father exercises 50/50 parenting time, he makes more money and thus contributes more. In the example above, Father would pay Mother the difference between $1,136.44 and $929.82. His total child support obligation comes to a mere $206.62 per month.

Is the Income Shares Model for Calculating Child Support Ever Not Applied?

A court may depart from the Income Shares Model to calculate child support if using them would be “inequitable, unjust, or inappropriate.” The court will look at the following factors in deciding whether to depart from these guidelines: 

  • Excessive medical expenses for the child or parent;
  • Additional expenses due to a child’s special medical, physical, or developmental needs; or
  • Any other factor that is in the best interest of the child. 

The law recognizes that, under certain circumstances, the Income Shares Model doesn’t account for the child’s needs or the parent’s abilities. In addition, sometimes, a court may order a parent to pay a higher amount of child support because their income is higher than what is listed on the Income Shares Model. Basically, the court can stray from the Income Shares Model if there is a compelling reason to do so.


Who Pays Child Support in Illinois?

Who pays child support depends on which parent has primary physical custody of the child. Typically the non-custodial parent pays child support to the custodial parent. A non-custodial parent doesn’t have primary physical custody of the child, usually under a court order or parenting plan. However, even a parent with joint, 50/50 split custody may have a child support obligation if each parent’s incomes are significantly different.    


How Long Does Child Support Last in Illinois?

A parent with a child support obligation must pay child support until the child is no longer a child. In Illinois, child support obligations typically end when the child turns 18. However, if the child is still in high school when they turn 18, then the child support obligation lasts until the child graduates from high school or turns 19, whichever comes first. 

If you missed some payments and your child turns 18, you still owe that child support. Just because the child turns 18 does not mean that your past unpaid child support obligations are suddenly gone. You will still owe back child support until you pay it off.


How Can I Get an Order for Child Support in Illinois?

In Illinois, there are two main ways to get an order of child support. You can go to the Department of Healthcare and Family Services and ask them to get a child support order on behalf of your child. In this case, neither you nor your child is bringing the case. Instead, the State brings the case on behalf of your child.

Another way to get an order for child support is to bring your case in Circuit Court. Although you can represent yourself, the child support laws are complicated. An experienced family attorney can best represent your interests in court.

If you and the child’s parent are divorcing, child support will typically be addressed as a part of the divorce, along with custody. An experienced divorce attorney will be able to advise you as to the child support aspect of your divorce case.


Can I Change a Child Support Order in Illinois?

Generally, a child support order cannot be modified unless one of the parties can show a substantial change in their circumstances. Examples of a substantial change in circumstances may include the child needing additional support due to a new medical issue or one of the parents experiencing a significant reduction in their income. 

If you want to change the child support order, you can’t just stop paying child support. You must make a motion to the court or go to the Department of Healthcare and Family Services. Then, you’ll have to wait for the court to decide if the circumstances warrant a change of the child support order. Speak with an experienced family law attorney if you’d like to modify your child support order. 


What Is Child Support?

Child support is financial support to help care for and raise a child. The issue of child support typically comes up when the child’s parents are no longer residing together. A divorce usually addresses child support, along with things like spousal maintenance, the division of assets, and child custody. Child support can also be addressed in a  proceeding on its own when the child’s parents are not married or when they are still married but separated. 

Illinois child support laws state that parents owe a duty of support to a child. The duty of support includes reasonable and necessary expenses related to providing for a child’s physical, mental, and emotional health. Reasonable and necessary expenses include:

  • Costs associated with a household, such as rent, utilities, and furniture;
  • School-related expenses, like books, supplies, uniforms, or tuition;
  • Necessities, such as clothes, food, toys, hygiene products, and diapers; and
  • Medical expenses, like copays, glasses, dental work, and medication.

The purpose of child support is to provide for the child’s needs. The parent receiving child support should not use it for their own needs or desires. 


Contact Us for Affordable Representation for Your Illinois Child Support Matter

You don’t have to decide between spending a fortune on an attorney or trying to represent yourself in a child support case. At Vantage Group Legal Services, we provide a subscription-based service, matching you to an experienced network attorney who will represent you when you need it most.

Contact us today for a free, no-pressure consultation with one of our attorneys.

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