The Ins and Outs of Child Support in Illinois

Child support is a likely conclusion if you have a child and are not married to the child’s mother/father, or if you are in the process of getting a divorce. Getting the full amount of support you are owed can be difficult and complicated. However, with the right attorney, you and your child can get the correct amount of child support due.

 Illinois Law

Under Illinois law, child support is due for any child whose guardian is not married to the child’s other parent. Child support should be used for the physical and emotional needs of the child, as well as medical needs, and educational expenses. The guidelines for support require the payment of 20 percent of net income of the non-custodial parent for one child, 28 percent for two children, 32 percent for three children, 40 percent for four, 45 percent for five, and 50 percent for six or more. This may sound straightforward, however, the difficulty may come in defining what one’s income may be.


Illinois uses net income as the standard for child support, as opposed to gross income.  Therefore, you have to look at what deductions the court takes from the gross income to figure the net income. Proper deductions are:

  1. Federal income tax;
  2. State income tax;
  3. Social Security;
  4. Mandatory retirement;
  5. Union dues;
  6. Health and life insurance;
  7. Additional child and spousal support obligations;
  8. Repayment of debts; and
  9. Foster care payments.


If the court believes that a proper support amount can be calculated by using traditional guidelines, a court can deviate from the guidelines by applying the following factors:

  1. The financial resources of the child;
  2. The financial resources of the custodial parent;
  3. The standard of living the child would have enjoyed if the parents had stayed married;
  4. The physical, mental, emotional, and educational needs of the child; and
  5. The financial resources of the non-custodial parent.

Additional Support

In addition to the set child support amount, a non-custodial parent can be ordered to pay daycare costs of the child, allowing the custodial parent to work. Further, the custodial parent is usually required to pay for health insurance for the child, but the non-custodial parent can be held responsible for a portion of the medical expenses not covered by insurance.


Child support can be modified upon a significant change in circumstances. A significant change could be a large increase or decrease in either parent’s salary. However, a decrease in the salary must be non-voluntary. Therefore, if you voluntarily quit your job, you cannot ask for a modification of support due to your unemployed status. However, if you are involuntarily laid off and no longer have a salary, you may ask for a modification. In addition, the court only has the ability to modify the child support obligation retroactive to the time the petition is filed. Thus, if you lose your job in January, but don’t file for a modification of support until March, the court can only change the child support amount from March going forward.

 Additionally, the decrease in the number of children receiving support is a change in circumstances. However, support will not be automatically changed when one child ages out if there are additional children receiving support. Illinois allows child support to be paid until the child is 18, or until 19 if the child is still in high school. When your child becomes too old for a support obligation, you must immediately file for a modification of support for the remaining children. The court does not have the ability to make the child support retroactive to the date the child ages out of the system, but only to the date of the filing of the petition. At this time, the court will re-calculate support using current income data.

Calculating child support and knowing when to ask for a modification can be confusing and difficult without a professional. The experienced Illinois family law attorneys at any one of our five offices can answer any questions you may have in regards to child support. Please contact us for a consultation.