Parenting time and child support in Illinois
Illinois uses a shared physical care calculation once each parent has the child for at least 146 overnights a year. Below that count the ordinary income shares calculation applies, so in Illinois the annual overnight count is the number that decides which calculation is used.
What is the parenting-time threshold in Illinois?
146
Illinois applies its shared physical care calculation when each parent has the child for at least 146 overnights a year. Below that count the ordinary Illinois income shares calculation applies instead, and above it the guideline recalculates on the basis that both households are running full time.
The Illinois count is of overnights across the whole year, so it is the annual rotation rather than a typical week that decides it. An Illinois schedule sitting close to the line is worth counting twice, because a handful of holiday nights either way changes which calculation the guideline uses.
- Illinois — 750 ILCS 5/505(a)(3.8), as published by the Illinois Department of Healthcare and Family Services (Income Shares FAQ). Verified .A 2026 amendment reported to lower the threshold to 110 overnights from January 1, 2027 is deliberately NOT recorded as a future change: ilga.gov, the only host carrying ILCS and Public Act text, refused every connection during verification, and no other primary source for it resolved. Secondary summaries are not a citation.
What to know before you file in Illinois
Illinois replaced the language of custody and visitation with allocation of parental responsibilities and parenting time, and the state courts publish a standardized parenting plan that every circuit court accepts. Filling in the Illinois plan is how a parent proposes the decision-making split and the schedule at the same time, in one document.
Because the Illinois calculation turns on a count of overnights, the plan has to describe the rotation precisely enough to be counted. An Illinois plan that says only "alternating weekends and shared holidays" cannot be counted by anyone; one that names the nights, the holiday rotation and the summer weeks can be counted by either parent.
Illinois expects a parenting plan to cover more than the calendar: transport, each parent’s right to information from schools and doctors, and the notice a parent must give before moving all belong in it. An Illinois plan that answers those in writing tends to need far fewer return trips to court later on.
The Illinois form
The Illinois statewide standardized parenting plan, published with the divorce and child support form suite, on which parents allocate decision-making responsibilities and set the parenting-time schedule.
Parenting Plan, Divorce With Children (statewide standardized form)