Child Support Basics in Illinois: How The Income Shares Model Works
- Nefertiti Mason
- 4 hours ago
- 1 min read

Introduction
Child support is designed to help meet a child’s financial needs after parents separate. Illinois uses an “income shares” model to calculate child support, which takes both parents’ incomes into account.
Understanding how this model works can help parents know what to expect.
What Is the Income Shares Model?
The income shares model estimates the amount parents would spend on their child if they lived together. That amount is then divided proportionally between the parents based on income and parenting time.
Factors Considered in Child Support Calculations
Illinois child support calculations may consider:
Each parent’s income
The number of overnights with each parent
Certain child-related expenses
Support amounts are calculated using state guidelines, though courts may adjust them in certain situations.
Modifications and Changes
Child support orders may be modified if there is a substantial change in circumstances, such as a job change or a significant shift in parenting time.
How Child Support Fits Into Your Family Law Roadmap
Child support decisions often occur alongside parenting plans and other family law matters. Understanding how support is calculated can help parents make informed decisions throughout their family law roadmap.
Frequently Asked Question
How does Illinois calculate child support under the income shares model?Illinois calculates child support by considering both parents’ incomes, parenting time, and certain expenses to determine a support amount that reflects the child’s needs.
Please call Larimer Law LLC today at (773) 902-0200 or email clerk@larimerlawllc.com to set up a free consultation with Angela Larimer to explore your specific family law needs. We are here for you when you need us!


