How Does Cheating Influence a Divorce in Illinois?

 Posted on September 26, 2026 in Divorce

While Illinois is a no-fault divorce state, an affair can become relevant if it involves marital money or affects your children. No-fault means the court will not weigh who was to blame when deciding whether to grant the divorce, and a judge cannot punish a spouse for cheating by handing the other one a larger share of the property. What the affair cost the marriage financially, and whether it exposed the children to anything, are separate questions a court can take up.

If infidelity played a role in the end of your marriage in 2026, a Naperville, IL divorce attorney can explain what to expect and help you protect your interests.

Does Cheating Give You Grounds for Divorce in Illinois?

Illinois no longer uses adultery as a legal ground for divorce. Under 750 ILCS 5/401 of the Illinois Marriage and Dissolution of Marriage Act, "irreconcilable differences" is the only basis for ending a marriage.

This means you do not need to prove that your spouse had an affair to get divorced. You also do not need your spouse to admit to cheating. Instead, you must show that irreconcilable differences have caused the marriage to break down and that attempts to reconcile have failed or would not be practical or in the family’s best interests.

Can Cheating Affect Property Division in an Illinois Divorce?

Illinois courts typically divide marital property without considering marital misconduct. As a result, a spouse does not automatically receive more property just because the other spouse had an affair.

However, cheating can become relevant if a spouse used marital property to pay for the affair. Under 750 ILCS 5/503, courts consider each spouse’s dissipation of marital property when dividing assets. Dissipation generally involves using marital property for one spouse’s sole benefit and for a purpose unrelated to the marriage after the marriage has begun to break down.

For example, a spouse might have used marital funds to pay for:

• Hotel rooms or vacations with a new partner
• Expensive gifts for the other person
• Restaurant meals and entertainment
• Rent or other living expenses for the other person

Not every purchase connected to an affair will qualify as dissipation, as it depends on the timing of the spending and the source of the money. If dissipation is proven, the court can take the lost marital funds into account when dividing property.

Is There a Deadline for Claiming Dissipation in Illinois?

Illinois law places limits on when a spouse can raise a dissipation claim. A notice of intent to claim dissipation must be given no later than 60 days before trial or 30 days after discovery closes, whichever is later.

There are also limits on how far back a claim can reach. A dissipation claim cannot cover conduct more than five years before the divorce petition was filed. It also cannot cover conduct more than three years before the spouse claiming dissipation knew or should have known about it.

If you believe your spouse spent a large amount of marital money on an affair, financial documents like bank statements or credit card bills can help show where the money went.

Does Cheating Affect Spousal Maintenance in Illinois?

Under 750 ILCS 5/504, Illinois courts make maintenance decisions without regard to marital misconduct. Instead, courts look at financial factors, such as each spouse’s income, property, needs, earning ability, and the length of the marriage.

This means a spouse who had an affair is not automatically prevented from receiving maintenance. Likewise, the other spouse is not automatically entitled to a larger maintenance award because of the cheating.

Can an Affair Affect Parenting Time or Parental Responsibilities in Illinois?

In most cases, infidelity alone does not affect parenting time or parental responsibilities. Illinois courts make these decisions according to the child’s best interests.

The law also states that courts should not consider a parent’s conduct if it does not affect that parent’s relationship with the child. Having an affair does not, by itself, mean that someone is an unfit parent.

However, circumstances involving a new partner can matter if they affect the child’s safety or well-being. For example, the court can consider conditions that could put the child at risk, such as violence or abuse. The focus is on how the situation affects the child, rather than on punishing a parent for being unfaithful.

Contact a Naperville Divorce Lawyer

An affair can make divorce more challenging emotionally. When it involves marital spending or concerns about your children, you want an experienced lawyer to help you understand how those issues could affect your case.

Attorney Don Pesce has almost two decades of experience handling Illinois family law matters. For a free consultation, contact the DuPage County divorce attorneys at Pesce Law Group, P.C. or call 630-352-2240.