A common concern of people with children in the divorce process is how child support is calculated in Illinois. In Illinois, the court will look at the gross income of both parents. This includes income from all sources, including, but not limited to, the following:
- Regular Employment
- Overtime (even if it is not guaranteed)
- Bonuses (even if they are not guaranteed)
- Second jobs
- Maintenance (including from former spouse)
However, gross income does not include income from public assistance programs (such as SSI or SNAP). It also excludes child support received from other children in the household.
What if a parent is underemployed?
The court can impute or credit income to someone voluntarily underemployed. Imputation of income is the process by which a court uses previous income and/or earning levels to set support. The court is required to make findings of specific factors in order to proceed with imputation on a party within a family matter. The statute requires as follows:
“If a parent is voluntarily unemployed or underemployed, child support shall be calculated based on a determination of potential income. In determining potential income, the court shall consider the specific circumstances of a party, to the extent known, including, but not limited to, the parent’s:
(1) assets;
(2) ownership of a substantial non-income producing asset;
(3) residence;
(4) employment and earning history;
(5) job skills;
(6) educational attainment;
(7) literacy;
(8) age;
(9) health;
(10) criminal records and other employment barriers; and
(11) record of seeking work.
The court shall also consider the local job market, availability of local employers willing to hire the parent, prevailing earning levels in the local community, and other relevant background factors in the case.” – 750 ILCS 5/505(a)(3.2a)
The gross income of each parent is converted to net income using the standardized income conversion chart provided by the Illinois Department of Healthcare and Family Services. The purpose of this chart is to determine how much money would be allocated for the care of the child/ren if a similarly situated couple were living together based on the combined income of the couple, the cost of living, and the number of children both within and outside the relationship.
Each parent is assigned their pro rata share of this child support amount based on their respective incomes (or potential incomes if the parent is voluntarily unemployed or underemployed).
The court will also determine whether a parent covers their child/ren on health insurance. If the party with the child support obligation is paying for health insurance, it will likely decrease their child support obligation by the portion the other parent would owe. On the other hand, if the parent receiving child support is paying for health insurance, the parent paying child support will owe their pro rata share for the cost of coverage for the minor child/ren.
What if we have equal parenting time?
Even if you have equal parenting time, you may still have a child support obligation. In Illinois, a parent has at least 146 overnights per year; up to 182 per year is considered equal parenting.
To calculate child support for shared parents, start by finding the basic support obligation on the income shares schedule as stated above. From there, you will increase the basic support obligation by 150% (multiplied by 1.5) to estimate the shared expenses between the parents’ households.
Note that the Illinois Child Support statute is set to update the allocation of a person’s percentage of income paid for support purposes as of January 1, 2027.
What if I have other children to support?
You may be entitled to the multi-family adjustment if you financially support other minor children.
If you have a court order to pay child support, the court shall deduct it from that parent’s new income. The amount of child support paid according to the order unless the court finds that it would cause economic hardship to the child for which child support is being determined.
You may request the multi-family adjustment if you are financially responsible for another child without a court order. The court shall deduct from the parent’s income the amount of financial support actually paid by the parent for the child or 75% of the support the parent should pay under the child support guidelines (before the adjustment), whichever is less. The court can deny the multi-family adjustment if it makes a finding that it would cause economic hardship to the child.
Does the judge have to follow the guidelines?
The judge may deviate to order a party to pay more or less than the guidelines suggest. For the judge to order a deviation, they must explain in writing their reasons for deviating from the guidelines.
What if I don’t have any income?
The court may impute their income if a party is voluntarily unemployed or underemployed. When a parent’s income is at or below 75% of the Federal Poverty Guideline for a one-person family, the court can order a $40 per month child support obligation per child, capped at $120.00. If a parent has no income for reasons beyond their control, such as disability or incarceration, the court can order them to pay $0 in child support.
If you have questions about child support, including what you may be obligated to pay or receive, do not hesitate to reach out to us to set up a consultation.
Key Take Aways
- Child support in Illinois is determined by calculating both parents’ gross income from all sources, excluding public assistance like SSI or SNAP.
- If a parent is voluntarily unemployed or underemployed, the court may impute income based on factors like earning history, job skills, and the local job market.
- Gross income is converted to net income using standardized charts, and parents are assigned a pro rata share of the support obligation based on their respective incomes.
- For equal parenting time (146-182 overnights), the basic support obligation is calculated and increased by 150% to account for shared household expenses.
- Courts may adjust support obligations if a parent supports other children (multi-family adjustment) or deviate from guidelines if they provide a written explanation.
- When income is very low, the court may order a minimal support payment, or $0 if unemployment is due to factors beyond a parent’s control like disability or incarceration.
Last Updated: September 8, 2026
