Illinois HFS•Income Shares Model
Illinois Child Support Calculator
Estimation using the "Shared Care" (146 Overnights) logic and HFS Gross-to-Net conversion tables.
Important: This calculator provides general estimates only and does not constitute legal advice. Use of this calculator does not create an attorney-client relationship with Steele Family Law or Beermann LLP. Results do not account for judicial discretion or case-specific factors. For advice regarding your specific situation, consult a licensed Illinois attorney.
1. Financial Inputs
$
Approx. Net: $0
$
Approx. Net: $0
$
$
2. Parenting Time (Overnights)
The 146 Night Rule: If each parent has the children for at least 146 overnights per year, the "Shared Care" formula applies, significantly reducing the support obligation.
Parent A: 290 nights
Parent B: 75 nights
Estimated Monthly Obligation
$0
Paid by Parent A
Basic Support Obligation (Combined)
$0
Shared Care Multiplier
None
Health Insurance Credit
-$0
Schedule Consultation
*Estimates based on HFS 2025 Schedule.
Understanding the "Income Shares" Model
Since 2017, Illinois has used the "Income Shares" model (750 ILCS 5/505). This philosophy holds that a child should receive the same proportion of parental income that they would have received if the parents lived together.
The Critical "146 Night" Cliff
The most litigated number in Illinois child support is 146. This is the threshold for "Shared Physical Care."
- Under 146 Nights: The parent with the majority of time receives the full basic support amount (prorated by income).
- 146 Nights or More: The Basic Support Obligation is multiplied by 1.5 (to account for duplicated household costs), and the obligation calculates across both parents based on time spent.