Imputing Income for Child Support in Illinois

What Imputed Income Means

When a parent's actual earnings don't reflect what they could reasonably be making, the court can assign a higher income figure for child support purposes. That assigned figure is called imputed income. Illinois courts do this under 750 ILCS 5/505 when a parent is voluntarily unemployed or voluntarily underemployed — meaning they've chosen to earn less than their capacity without a legitimate reason. A court may impute income only after an evidentiary hearing or by agreement of the parties, and the imputation must be accompanied by specific written findings.

The distinction matters because the Income Shares Model calculates child support based on both parents' net incomes. If one parent quits a $90,000 salary to work part-time at $25,000 right before a custody filing, the child support obligation based on actual income would be artificially low. Imputation corrects for that.

When Courts Impute Income

Illinois judges look for a pattern of voluntary income reduction, not temporary setbacks. A parent laid off during a recession and actively job-hunting is not voluntarily underemployed. A parent who left a management role to become a freelance artist six months before filing is a different story.

Common situations where courts impute income:

• A parent quits or takes a demotion shortly before or after a support petition is filed
• A parent with professional credentials or significant work history chooses not to work at all
• A parent takes cash-only or under-the-table work to suppress documented earnings
• A parent transfers assets or business income to reduce reportable personal income

Courts do not treat every reduction as voluntary. A genuine disability, primary caregiving of a very young child, or enrollment in a degree program may be relevant to the court's analysis, but none automatically prevents imputation.

How the Court Calculates Imputed Income

There is no single formula. The judge evaluates what the parent could reasonably earn based on:

• Employment history and credentials — degrees, licenses, certifications, and prior salary levels
• Age and physical capacity — a 28-year-old with an engineering degree is treated differently than a 62-year-old with a chronic back injury
• Local job market conditions — the court considers what jobs are realistically available in the parent's geographic area
• Past earning patterns — tax returns and other financial records showing prior earnings establish a useful baseline

The court may rely on expert testimony from a vocational evaluator — a professional who assesses the parent's skills, experience, and the current labor market to produce a specific earning capacity figure. These evaluations typically cost $2,000-$5,000.

What Evidence You Need

If you're requesting imputation, the burden is on you to show the other parent is earning below capacity without good reason. Useful evidence includes:

• The other parent's recent tax returns and W-2s showing the income decline
• LinkedIn profiles or resumes documenting credentials and work history
• Job postings in their field showing available positions and salary ranges
• Testimony about lifestyle spending that doesn't match reported income
• Documentation of voluntary career changes (resignation letters, social media posts about "taking time off")

If you're the parent whose income might be imputed, keep records of your job search — applications, interviews, rejection letters — and any legitimate reasons for reduced earnings.

Imputation and SB3524 Changes

Starting January 1, 2027, Senate Bill 3524 adds specific protections for parents at the lowest income levels. A parent whose gross income is at or below 100% of the Federal Poverty Guidelines for a single-person household will have a rebuttable presumption of a minimum support obligation of $40 per month per child, capped at $120 per month total. Parents incarcerated for more than 180 continuous days will have a rebuttable presumption of inability to pay any support.

These provisions don't eliminate imputation — a court can still impute income above the poverty threshold if the evidence supports it. But they establish a floor that protects genuinely low-income parents from support orders they cannot meet.

How Imputed Income Affects Your Parenting Plan

The income figure used in the child support calculation — whether actual or imputed — feeds directly into the parenting plan's financial structure. If you're negotiating a shared care arrangement with 146 or more overnights (110 starting in 2027), the support offset depends on accurate income figures for both parents.

Our Illinois Child Custody & Parenting Plan Guide includes worksheets for documenting both parents' income sources and modeling support under different overnight schedules — a useful baseline whether you're the parent requesting imputation or defending against it.

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