Which State Decides Custody? How the UCCJEA Works in Illinois

How Illinois Law Works

• Illinois has adopted the Uniform Child-Custody Jurisdiction and Enforcement Act (UCCJEA), which nearly every state also follows.
• The child’s home state, based on six consecutive months of residence before filing, has first priority to decide custody.
• The state that issued a custody order generally keeps exclusive authority to change it while a parent or the child still lives there.
• Illinois courts can act temporarily in an emergency to protect a child who is present in the state.
• International abduction cases may fall under the Hague Convention, which focuses on returning the child rather than deciding custody.

What Is the UCCJEA?

The UCCJEA is a uniform law that tells courts which state has authority to decide custody matters so that two states don’t issue competing orders. Illinois adopted it as 750 ILCS 36, and it applies to both initial custody decisions and later modifications.

Why the Law Exists

Before the Uniform Act, a parent could sometimes move a child to a new state and ask a local court for a better result. The UCCJEA removes that incentive by setting clear priority rules and requiring states to enforce each other’s orders.

It replaced an older uniform act whose looser standards sometimes let two states claim authority over the same child.

How It Fits Illinois Terminology

Illinois no longer uses the word “custody” in its divorce statute, and instead speaks of the allocation of parental responsibilities and parenting time. The UCCJEA still uses “child-custody determination,” and that term covers Illinois orders on decision-making and parenting time.

How Is a Child’s Home State Determined?

A child’s home state is the state where the child lived with a parent, or someone acting as a parent, for at least six consecutive months immediately before the case was filed. The Illinois act spells out a few details that often decide close cases:

• For a child younger than six months, the home state is where the child has lived since birth.
• Temporary absences, such as vacations or summers with the other parent, count as time in the home state.
• A state can remain the home state for six months after the child leaves, as long as a parent still lives there.
• The date of filing controls, so the six-month count looks back from the day the case is opened.

Consider a family that lived in Lake County for years before one parent moved with the child to Wisconsin while the other parent stayed. For six months after that move, Illinois remains the home state, so a case filed in Lake County during that window usually belongs in Illinois.

When There Is No Home State

When no state qualifies as the home state, an Illinois court can decide custody if the child and at least one parent have a significant connection to Illinois and substantial evidence about the child is available here. This situation often arises when a family moved recently or split time between states.

Significant Connection Jurisdiction

Courts look at where the child goes to school, sees doctors, attends activities, and has family ties. A child who moved to Elgin three months ago, after years of moving between states, may still have the strongest connection to Illinois.

The ties of a grandparent or other adult acting as a parent can count when the child lives with that person.

When a Court Declines to Hear the Case

An Illinois court that has jurisdiction can still decline it as an inconvenient forum under Section 207. The court weighs several factors, including:

• Whether domestic violence has occurred and which state is better positioned to protect the child
• How long the child has lived outside Illinois
• The distance between the courts and the financial circumstances of each parent
• Where the evidence and witnesses are located, and any agreement the parents made

A court may also refuse jurisdiction under Section 208 when a parent created it through unjustifiable conduct, such as hiding a child in a new state to build up residence time.

Does Illinois Keep Jurisdiction After a Parent Moves Away?

Illinois keeps exclusive, continuing jurisdiction over its own custody order as long as the child or a parent still lives in Illinois. Under Section 202, that authority ends only when an Illinois court finds the connection is gone or when the child and both parents have all left the state.

What This Means for Modification

Another state cannot modify an Illinois order while Illinois keeps that authority. If a Colorado court issued the original order and one parent still lives there, an Illinois court cannot change it unless Colorado gives up its authority, even after the child moves to McHenry County. To modify an existing custody order, a parent starts in the state that holds that authority.

Where Relocation Fits

Moving with a child raises a separate question, with its own rules for moving out of state with your child under Illinois law. Jurisdiction answers which court decides, not whether the move itself is allowed.

Emergency Jurisdiction When a Child Is at Risk

An Illinois court can take temporary emergency jurisdiction when a child is in Illinois and has been abandoned, or when the child, a sibling, or a parent faces mistreatment or abuse. Section 204 allows that authority even when another state would normally decide custody.

How Long an Emergency Order Lasts

An emergency order is temporary by design. If another state has jurisdiction, the Illinois order generally lasts only until that state’s court acts, and the Illinois judge must contact the other court to coordinate.

What It Does Not Do

Emergency jurisdiction protects a child in the moment, but it does not move the whole case to Illinois. The parent seeking protection still needs to address the long-term custody question in the proper state.

What Happens When Parents File in Two Different States?

When parents file in two different states, the courts are required to communicate and sort out which one has priority under the UCCJEA. An Illinois court cannot proceed if a case was already properly started in a state with jurisdiction.

The process usually unfolds in this order:

1. The Illinois court checks for any pending case in another state, using the information each parent must provide when filing.
2. The judges communicate directly, and the parents may be given a chance to present facts and arguments.
3. The court with home-state or other priority jurisdiction keeps the case.
4. The other court stays or dismisses its proceeding, sometimes after entering a temporary order.

Filing first rarely changes the outcome because priority comes from jurisdiction rather than speed. Accurate dates for every move and address change are among the most useful evidence a parent can bring.

Registering and Enforcing an Out-of-State Custody Order in Illinois

An out-of-state custody order can be registered in an Illinois circuit court, and once registered, it is enforced like an Illinois order. Article 3 of the act sets out how registration and enforcement work:

1. A parent files a request with copies of the order and a sworn statement that it hasn’t been modified.
2. The court serves notice on the other parent.
3. The other parent has 20 days after service to contest registration on narrow grounds, such as a lack of jurisdiction in the original court.
4. If registration is not contested or the challenge fails, the order is confirmed.
5. For urgent enforcement, a petition for expedited enforcement generally leads to a hearing on the next judicial day after service.

Illinois courts enforce registered orders but cannot modify them unless Illinois independently has modification jurisdiction. When a child is likely to suffer serious physical harm or be removed from the state, Section 311 allows a court to issue a warrant to take physical custody.

When Does the Hague Convention Apply Instead?

The Hague Convention applies when a child under 16 is wrongfully taken to or kept in a different country that is a treaty partner with the United States. It provides a civil return remedy, and custody itself is then decided by the courts of the child’s habitual residence.

This table compares the two frameworks:

Under the federal Hague implementing law, Illinois state courts and federal courts share jurisdiction over these return cases. Illinois courts can also enforce a Hague return order as if it were a custody determination.

Defenses a Court May Consider

A Hague court can refuse return in limited situations, such as when the case was filed more than a year after the removal and the child is now settled, or when return would expose the child to a grave risk of harm. The parent opposing return carries the burden of proving these exceptions.

When the Other Country Is Not a Treaty Partner

If the other country has not partnered with the United States under the Convention, the return remedy is not available. Illinois still treats a foreign country like another state under the UCCJEA, but enforcing an Illinois order abroad depends on that country’s own courts.

Illinois Custody Jurisdiction Questions Answered by Our Barrington Attorneys

Does the UCCJEA apply to child support?

No, the UCCJEA does not govern child support. Interstate support cases fall under a separate uniform law, the Uniform Interstate Family Support Act, which has its own rules for which state can set and change a support order.

Can parents agree to let a different state decide custody?

Parents cannot create jurisdiction by agreement alone if the UCCJEA doesn’t give that state authority. An agreement can still matter because Illinois courts consider it when deciding whether another state is the more convenient forum.

Is taking a child to another state without permission a crime in Illinois?

It can be. Illinois treats concealing, detaining, or removing a child in violation of a court order as a form of child abduction, and federal law separately criminalizes removing a child from the United States to obstruct parental rights.

Do Illinois judges talk to judges in other states?

Yes, the UCCJEA allows an Illinois judge to communicate directly with a judge in another state about jurisdiction. The parents may be allowed to take part, and the court keeps a record of any communication that goes beyond scheduling.

Will another state enforce an Illinois custody order?

Yes, every state that follows the UCCJEA must recognize and enforce a valid Illinois custody order, and the federal Parental Kidnapping Prevention Act requires every state to honor those orders. A parent in another state typically registers the Illinois order there before seeking enforcement.

Starting From Clarity

Questions about which state decides custody often feel bigger than they are because the rules are more predictable than they first appear. Once the right court is clear, the energy can go to the parenting plan and the child’s stability instead of a fight over location.

The Law Offices of Lawrence S. Manassa, P.C., works with families in Barrington and across Lake, Kane, McHenry, and northwest Cook counties. If a custody question crosses state lines, call 847-221-5511 to schedule a free consultation at our Barrington office.