When Can You Ask the Court To Change a Custody Agreement in Illinois?

 Posted on September 08, 2025 in Child Custody

Parents who share custody of their children sometimes find that life changes impact their parenting. When this happens, the parenting plan that once fit the family’s needs may no longer serve the best interests of the child. If you need to modify your existing plan, an experienced Orland Park, IL child custody lawyer can guide you through the process and help you understand what the court requires to make a change.

Understanding Custody Agreements Under Illinois Law

In Illinois, the law uses the term "allocation of parental responsibilities" rather than "custody." This includes both decision-making authority and parenting time. Once a parenting plan has been entered by the court, it is legally binding.

Under 750 ILCS 5/610.5(a) of the Illinois Marriage and Dissolution of Marriage Act, courts generally require parents to wait two years before filing a request to change decision-making authority. Parenting time, however, can sometimes be adjusted sooner if there is a good reason.

What Counts as a "Substantial Change in Circumstances" in an Illinois Custody Modification Case?

The court will not approve a custody modification without proof of a "substantial change in circumstances." This standard is designed to provide stability for children, and common examples include:

• A parent relocating far enough away to disrupt the parenting schedule

• A significant shift in a parent’s work hours that makes the current schedule unworkable

• Serious health issues affecting a parent’s ability to care for the child

• Evidence of neglect, abuse, or ongoing substance abuse

• A parent’s repeated failure to follow the existing custody order

• The child’s needs evolving as they grow older and require different arrangements

• Both parents agreeing that the current plan no longer serves the child’s best interests

Under 750 ILCS 5/610.5(c), the court may also consider whether both parents agree to the change, which can make the process easier.

The Legal Process for Requesting a Custody Modification

To start, a parent must file a petition to modify the allocation judgment in the circuit court that issued the original custody order. This petition should clearly explain what has changed and why modifying the arrangement is in the child’s best interests.

The other parent has the right to respond, and the court may require both parties to attend mediation, under 750 ILCS 5/602.10, before a full hearing. However, if an agreement cannot be reached, a judge will hold a hearing and issue a decision. If you file the petition, you can use school records, medical reports, or witnesses to support your claims.

Contact a Joliet, IL Parental Responsibilities Attorney

To change a custody order in Illinois, you must show more than just a change in circumstances. You must also prove that the change benefits your child. Because the process is complex and emotionally charged, working with experienced Orland Park, IL child custody lawyers is the best way to present your case effectively.

At The Foray Firm, we are proud members of the Black Women Lawyers' Association, the Black Bar Association of Will County, the Cook County Bar Association, and the National Bar Association. With strong community ties and a deep understanding of Illinois family law, we are ready to stand by you and help you pursue a modification that truly supports your child’s best interests while protecting your parental rights. Call 312-702-1293 to schedule a consultation today.