2017 Illinois Child Support Calculation Changes

Prior to July 1, 2017, the standard Illinois child support calculation was based on a flat percentage of the net income of the paying parent:

# Children% Net Income
120%
228%
332%
440%
545%
6+50%

New Income Shares Model

However, in an effort to implement child support guidelines that better reflect the unique needs of families, cases involving child support filed on or after July 1, 2017 will use the income shares model for calculating child support. The goal of the income shares model is to determine the amount of each parent's income that would have gone to the care and support of the child(ren) if the parents had remained living together. The income shares model is used in nearly all U.S. states, and is different from the flat percentage of net income model in that it considers both parents’ incomes to determine a basic support obligation owed to the child(ren) and then requires the parent who is paying support, also known as the obligor, to pay a percentage of that obligation relative to that parent's share of the household income. With the income shares model, parenting time can be a factor in the amount of child support the obligor pays. The flat percentage model previously used did not take parenting time into account in calculating child support.

Calculating Child Support Using the Income Shares Model

If you use DivorceWriter to create your Illinois divorce forms, DivorceWriter automatically calculates your standard child support using the new income shares model. You may choose a different amount than the calculation, but be aware that the judge will make sure that your deviation is in the best interests of the children. Below are the basic steps that are used to calculate Illinois child support using the new model.

  1. Determine the gross monthly income of each parent.
    Include income from all sources including Social Security dependent allotments for any children the couple have together as well as spousal support from the other spouse, but do not include TANF, SSI, SNAP, or any income received in child support for other children in your home from other relationships. Note: If one of you is paying spousal support (alimony) to the other, it is deducted from the gross income of the paying spouse and added to the gross income of the spouse receiving the alimony.
  2. Determine the adjusted net income of each parent by subtracting the taxes and other deductible amounts.
    If a parent is paying child support or spousal support to persons unrelated to this marriage—i.e. children or spouse from another relationship—that amount is deducted from that parent's gross income.
  3. Combine the adjusted net income of both parties.
    Assume that the adjusted net income for husband is $3,000 for husband and is $2,000 for wife, for a combined net income of $5,000.
  4. Determine the Basic Child Support Obligation by finding the parents' combined adjusted net income on the Income Shares Based on Net Income Schedule.
    Assuming the parties have just one child and a combined net income of $5000, the Basic Child Support Obligation is $943 according to the schedule.
  5. Determine each parent's percentage share of net monthly income by dividing each parent’s net monthly income by the parents' combined total adjusted net monthly income.
    If the total net monthly income is $5,000/month, $3,000 of which is Husband's and $2,000 of which is Wife's, then Husband's percentage to be paid of the basic support obligation is 3000 ÷ 5000=0.6 or 60%, and Wife's percentage to be paid is 2000 ÷5000=0.4 or 40%.
  6. Determine each parent's contribution toward the basic child support obligation.
    In Step 4 it was determined that the basic child support obligation is $943, and Husband's percentage share is 60% and Wife's is 40%, so if Husband is the obligor he will pay 60% of $943, or $565.80, and if Wife is the obligor, she would pay 40% of $943, or $377.20, for one child.
  7. Adjust the basic child support obligation for shared physical care, certain expenses and health care, as applicable.
    If the parties share physical care, which is defined as each parent having at least 146 overnights with the child(ren) per year, you will use the Shared Physical Care Support Obligation Worksheet, which includes a formula for parenting time credit. If only one of the parties has 146 overnights or more with the child(ren) per year, use the Support Obligation Worksheet, which gives credit to a parent paying for extraordinary extracurricular activities/school expenses and child care expenses. Both worksheets give credit to the parent who is providing health insurance for the child(ren).

How Parenting Time Affects Child Support

As was explained above Shared Physical Care occurs when each parent has at least 146 overnights, which is 40% of the year, with the child(ren). Because the new income shares model takes parenting time into account in arriving at the standard guideline child support amount, some fear that it will result in parents arguing more over custody and parenting time. In other words, the concern is that a parent may insist on having more parenting time than he or she ordinarily would to get a reduction in child support. When this happens, it is argued, parents may find themselves in court on custody matters more often.

Choosing a Different Child Support Amount

The child support amount calculated using the income shares model is presumed by the court to be the right amount for your family's circumstances. However, that presumption is rebuttable and couples routinely agree to a higher or lower amount. According to Illinois law, the court may deviate from the child support guidelines if the guideline amount would be inequitable, unjust, or inappropriate. Any deviation from the guidelines shall be accompanied by written findings by the court specifying the reasons for the deviation and the presumed amount under the child support guidelines without a deviation. These reasons may include (A) extraordinary medical expenditures necessary to preserve the life or health of a party or a child of either or both of the parties; (B) additional expenses incurred for a child subject to the child support order who has special medical, physical, or developmental needs; and (C) any other factor the court determines should be applied upon a finding that the application of the child support guidelines would be inappropriate, after considering the best interest of the child.

When the New July 1, 2017 Guidelines Apply

The new income shares child support guidelines apply to all child support cases where support will be set on or after July 1, 2017. If child support has already been set in your case, the new law does not automatically entitle you to modify, or change, child support. To be eligible for a modification of child support, there usually must have been a significant change in the financial circumstances of one or both of the parties or, in the alternative, the current child support order must have been set at least three years ago. If that applies in your case and you receive services from the Illinois child support program, you're entitled to ask them to review your case for a modification request. If you meet the criteria, but are not being represented by the Illinois child support program, you can file for modification yourself or hire an attorney to do it for you.