Illinois Child Custody Laws: How Custody Is Decided

Illinois no longer awards "custody" of a child. Instead, an Illinois court divides parental authority into two separate pieces: parenting time (the schedule of when the child is physically with each parent) and significant decision-making responsibilities (who has the legal authority to decide the child's education, health care, religion, and extracurricular activities). A judge allocates both based on what is in the child's best interests. If you and the other parent agree in writing and the court approves your parenting plan, the two of you decide these things yourselves; otherwise, a circuit court judge decides for you.

"Custody" Became "Allocation of Parental Responsibilities"

Illinois law replaced the old custody/visitation framework with the "allocation of parental responsibilities." That allocation has two parts: parenting time and significant decision-making responsibilities. Significant decision-making specifically covers education, health, religion, and extracurricular activities. Parents can also share day-to-day "caretaking functions" for a child — things like meals, hygiene, bedtime routines, and care when a child is sick — separately from who holds the legal decision-making authority.

You will see this terminology throughout an Illinois family law case: the "allocation judgment" is the court order that spells out each parent's parenting time and decision-making responsibilities.

How Illinois Decides Parenting Time

Illinois law starts from a presumption that both parents are fit. The court is not allowed to place restrictions on a parent's parenting time unless it finds, by a preponderance of the evidence, that the parent's exercise of parenting time would seriously endanger the child's physical, mental, moral, or emotional health. Short of that finding, the court allocates parenting time according to the child's best interests, weighing the factors set out in the parenting-time statute.

In practice, this means Illinois courts do not start from an assumption that one parent — such as the mother — automatically gets more time, and they are not supposed to punish a fit parent by cutting them out of the schedule. A parent seeking to restrict the other parent's time carries the burden of proving serious endangerment.

Decision-Making Responsibilities: Who Decides the Big Things

Separately from the day-to-day schedule, the court allocates who has the authority to make significant decisions in four areas: education, health, religion, and extracurricular activities. Parents can be given decision-making authority jointly, the responsibility can be split by subject (for example, one parent decides health care and the other decides schooling), or one parent can be given sole significant decision-making authority. As with parenting time, the standard the court applies is the child's best interests.

Moving With Your Child: Illinois's Relocation Rules (Time-Sensitive)

If a parent with parenting time responsibilities wants to move with the child, Illinois law treats certain moves as a "relocation" that requires formal notice — and the mileage threshold depends on which county the child currently lives in. Under Illinois law, a move counts as a relocation if it is:

• More than 25 miles from the child's current home, if that home is in Cook, DuPage, Kane, Lake, McHenry, or Will County;
• More than 50 miles from the child's current home, if that home is in any other Illinois county; or
• More than 25 miles to a new residence located outside Illinois.

Distance is measured using an internet mapping service and surface roads (not a straight line "as the crow flies").

This is time-sensitive: a parent who has been allocated a majority of the parenting time — or either parent, if parenting time is equal — may seek to relocate, but Illinois law requires at least 60 days' written notice before the move, unless that much notice is impracticable. The notice must be filed with the clerk of the circuit court. A relocation under this rule is automatically treated as a "substantial change in circumstances," which is significant because it is what allows a court to revisit the existing allocation order. If you are the parent planning to move, or the parent who just found out the other parent plans to move, the 60-day notice clock is the single most important date to track — talk to the Illinois circuit court clerk's office or a family law attorney promptly rather than assuming the move can happen informally.

Changing a Custody Order Later: Modification Rules

Illinois draws a sharp line between modifying decision-making responsibilities and modifying parenting time:

• Significant decision-making responsibilities: Generally, no motion to modify decision-making may be filed earlier than 2 years after the existing order's date. The court can allow an earlier motion only if affidavits show reason to believe the child's present environment may seriously endanger the child's mental, moral, or physical health.
• Parenting time: Parenting time can be modified at any time, without waiting 2 years and without a showing of serious endangerment — the standard is simply a showing of changed circumstances that necessitates modification to serve the child's best interests.
• Illinois law also allows minor modifications, and modifications that just reflect the actual parenting arrangement the parents have followed for the prior six months, to be made without the changed-circumstances showing otherwise required.

If your situation has changed and you are unsure which category your request falls into — or whether the 2-year bar applies to you — that timing distinction is worth confirming directly with the circuit court before you file anything.

When Another State, a Tribe, or Another Country Is Involved

A few federal laws layer on top of Illinois's own rules in cross-jurisdiction situations:

• Interstate custody disputes: The federal Parental Kidnapping Prevention Act (28 U.S.C. § 1738A) requires every state to give full faith and credit to a custody or visitation order issued by the child's home state, and it forbids a second state from modifying that order while the original state still has jurisdiction. This dovetails with the state-enacted Uniform Child Custody Jurisdiction and Enforcement Act, which governs which state's courts have authority to decide custody in the first place.
• Native American children: If the case involves a Native American child, the federal Indian Child Welfare Act (25 U.S.C. §§ 1901–1923) sets minimum federal standards, gives tribes notice and a jurisdictional role, requires "active efforts" to keep the family together, applies a heightened burden of proof, and sets placement preferences favoring relatives and tribal homes.
• International abduction: If a child has been wrongfully taken to, or kept in, the United States from another country, the International Child Abduction Remedies Act (22 U.S.C. § 9001 et seq.) implements the Hague Convention and provides a federal court process to seek the child's return to their country of habitual residence. That process decides return of the child — not who should ultimately have custody.

If a Parent Is in the Military

A servicemember whose military duties materially affect their ability to appear in an Illinois custody case can request a stay under the federal Servicemembers Civil Relief Act (50 U.S.C. § 3932). The stay must be for at least 90 days and is meant to protect deployed or active-duty parents from a default judgment or from being forced to litigate a divorce, custody, or support case while unable to participate.

What You Can Do in Illinois

1. Identify what's actually in dispute. Decide whether you're contesting parenting time, significant decision-making, or both — the rules and deadlines differ for each.
2. Try a written parenting plan first. If you and the other parent can agree, a court-approved written parenting plan lets the two of you set the allocation instead of a judge deciding it for you.
3. If a move is coming, count the days. If your move (or the other parent's) crosses the relevant mileage threshold for your county, calendar the 60-day written notice requirement and file it with the circuit clerk as soon as the move is realistic — don't wait until it's imminent.
4. Check the modification timeline before you file. If you're trying to change decision-making responsibilities, confirm with the circuit court whether the 2-year waiting period applies to your order, or whether your facts support an earlier endangerment-based filing.
5. Flag cross-border or military issues early. If another state, a tribe, another country, or a servicemember parent is involved, say so up front — these federal laws can change which court can act and on what timeline.
6. Confirm current local procedure. Circuit court filing procedures and local forms vary; contact your Illinois circuit court clerk's office (or an Illinois family law attorney) to confirm current requirements before you file.

This article is general information about Illinois law, not legal advice for your situation — confirm current details with an Illinois court or attorney.