How Much Child Support Will I Have to Pay?

 Posted on January 17, 2026 in Child Support

When parents separate or divorce, figuring out child support can feel confusing. Many parents are worried about how much child support they will have to pay. Many parents also worry if their spouse will be required to pay enough. If you are going through this in 2026, our Naperville, IL family law attorneys can help you understand how Illinois courts calculate child support and what you might pay or receive.

How Does Illinois Determine Child Support?

Illinois uses a specific formula, called the Income Shares Model, to calculate child support amounts. This model is based on the idea that children should get the same amount of money they would have received if their parents had stayed together. Understanding how this calculation works can give you peace of mind and help you plan for your future.

Under 750 ILCS 5/505, Illinois looks at both parents' incomes and combines them. There are two formulas that can be used to figure out net income: the "standardized tax amount formula" and the "individualized tax amount formula." The standardized tax formula is more common and used for anyone who takes the standard tax deduction. The individualized tax formula is used for people who have more complicated tax situations.

The state then uses a chart called the Schedule of Basic Child Support Obligations to figure out how much it costs to raise a child at that income level. Each parent pays a part based on what percentage of the total income they earn. For example, if the parents' combined income is $6,000 per month and one parent earns $4,000 while the other earns $2,000, the first parent would have to pay about 67 percent of the child support amount. The other parent would cover about 33 percent. The amount of parenting time each parent has can further affect these calculations. 

Illinois updates its Schedule of Basic Child Support Obligations regularly. This means the amounts are based on current information about how much it costs to raise children in Illinois today.

Can the Court Change the Child Support Amount for Special Circumstances?

Illinois judges can adjust child support amounts if using the standard formula would not be fair in your situation. The judge must explain in writing why the standard calculation does not work for your case.

Courts might increase child support if your child has special needs or needs ongoing medical treatment. They might decrease it if paying the standard amount would not leave you enough money to meet your own basic needs.

If one parent is not working or working less than they could, the court might assign them child support based on what they should be able to earn. This is called "imputing income." The court looks at education, work history, and available jobs in the area to decide what someone could reasonably earn.

What If My Income Changes After Illinois Child Support Is Ordered?

Child support orders can be modified when things change. If you lose your job, get a big raise, or have other major financial changes, you can ask the court to review your child support amount. Other big changes – called a "substantial change of circumstances" – could be moving to a new city, the child or parent getting a new disability, or issues of abuse showing up.

Illinois also allows child support orders to be reviewed every three years without a substantial change of circumstances. Either parent can request this review to make sure the amount still makes sense based on current incomes and needs.

Keep in mind that you cannot quit your job or take a lower-paying position just to reduce your child support payments. The court will look at whether income changes were voluntary and whether you are acting in good faith.

Call a DuPage County, IL Child Support Lawyers Today

Understanding how Illinois calculates child support is important for planning your financial future after separation or divorce. The Naperville family law attorneys at Pesce Law Group, P.C. have over 20 years of experience and can walk you through what child support may be for your specific case. This will help you understand what to expect down the road. Contact us today at 630-352-2240 for a free consultation to discuss your child support questions.