What is Commingled Property in an Illinois Divorce?

 Posted on May 08, 2026 in Property Division

When any couple gets divorced in Illinois, one of the many issues they will have to address is how property will be divided between the two of them. The property division process can be taxing, especially if spouses cannot agree on how the property should be distributed. In some cases, issues can arise when one spouse does not agree with the marital and non-marital property designations assigned to certain assets. 

Many couples have expensive and valuable assets, such as the family home, vehicles, and perhaps even a business or professional practice. Determining a correct designation for those assets is crucial to getting a fair distribution of marital property. However, determining what is and is not marital property is not always as clear-cut as you would think. At The Stogsdill Law Firm, P.C., our Wheaton, IL divorce lawyers have over 100 years of shared legal experience, allowing us to shed light on complex property matters.

How Do You Tell the Difference Between Marital and Separate Property in 2026?

In Illinois, only marital property is included in the division process. This means that any property or debts you and/or your spouse acquired during your marriage are fair game, with a few exceptions. Property is considered non-marital property acquired during the marriage if it was:

• A gift given to you only

• Acquired through legacy or descent

• Acquired in exchange for property you acquired before the marriage

• Property excluded from the marital estate by a valid prenuptial or postnuptial agreement

Even if you acquire this property during the course of the marriage, it is still considered the personal property of the person who received it. When marital property and non-marital property are mixed, they are considered to be "commingled." If an asset loses its identity as non-marital property, it becomes marital property. This means that both spouses are entitled to a portion of the commingled property's value.

What Happens to Commingled Property During Asset Division in Illinois?

Illinois courts use equitable distribution during asset division. This means the court divides marital property in a fair way, not always equally. A judge may look at each spouse’s income, needs, age, health, debts, work history, and role in the marriage. The judge may also consider how each spouse helped get, keep, or raise the value of the property. 

Illinois law says marital property must be divided in "just proportions" (750 ILCS 5/503). This can take each spouse’s needs into account after the divorce. However, the judge will not factor in any misconduct or fault behind the divorce when dividing commingled property.

Spouses do not have to let a judge decide every issue. Many couples settle outside of court through negotiation, mediation, or a written marital settlement agreement. A settlement is not subject to the same decision-making rules that a judge must follow at trial. Spouses may trade assets, divide accounts in a set way, or let one person keep disputed property.

How Does Property Become Commingled in an Illinois Divorce?

Commingled property is common in divorce. There are many ways that something that was once non-marital property can become marital property. One of the best examples of that is when there is a business involved. A spouse may have acquired the business prior to getting married, but the business likely increased in value throughout the marriage. The increase in value of the business can be subject to division and would likely require the business owner to reimburse his or her spouse for that value.

Illinois courts may recognize when one spouse, or the marital estate, helped improve or preserve the other spouse’s non-marital property. One spouse may help pay the mortgage on a home the other spouse owned before marriage. Marital money may be used for repairs, taxes, or loan payments.

Another example would be inheritance. If one spouse received a sum of money from a trust fund or inheritance and subsequently put that money into a joint bank account, it could be argued that the money is then the property of both spouses. You could also argue that anything purchased with the use of those funds would be considered marital property.

These facts do not always turn separate property into marital property. However, they may create a right to reimbursement. The spouse asking for credit usually needs clear records. The court will want to know what was paid, where the money came from, and whether the payment was meant as a gift. Without proof, the claim may fail.

Important Considerations When Using a Prenup To Protect Separate Property in Illinois

A prenuptial agreement can help protect separate property before marriage. It can say that certain assets, income from those assets, or increases in value will remain separate. This can help when one spouse owns a business, real estate, retirement savings, or family property before the wedding. For many couples, this is preferable to tedious litigation over who owns a particular asset.

However, a prenup is not automatically enforced. A court may reject part or all of it if problems exist. A prenup may be challenged if one spouse did not sign it voluntarily. Pressure right before the wedding can create problems. Allegations of threats, hidden assets, or false financial information can also jeopardize an agreement.

A court may also look at whether both people had a fair chance to understand the agreement. Each spouse should have time to review it. The agreement should be clear, complete, and signed well before the wedding.

Contact Our DuPage County, IL Divorce Property Division Attorneys Today

Even if an asset was originally considered non-marital property, it can take on characteristics of marital property. If you are unsure of the designation of your assets, you should discuss your situation with a knowledgeable Wheaton, IL property division lawyer. The team at The Stogsdill Law Firm, P.C. can help you classify your property so you receive a fair share of the marital estate. To schedule a consultation, call our office today at 630-462-9500.