What Is the Purpose of a Cohabitation Agreement in Illinois?

 Posted on August 14, 2025 in Cohabitation

A cohabitation agreement is a legal document signed by two people who live together but are not married. This agreement helps set clear expectations about each person’s responsibilities during the relationship. It also addresses what will happen if the relationship ends or if one partner passes away. It can cover things like property division, financial support, and other personal matters. If you are planning to live together in Illinois, talking to a DuPage County, IL family law attorney can help make sure your agreement is legally correct.

Is a Cohabitation Agreement Enforceable Under Illinois Law?

Cohabitation agreements in Illinois are treated as contracts, but their enforceability is limited. The agreement may be upheld for things like property division or asset agreements, but Illinois does not enforce financial support or palimony after a breakup. This is because Illinois law does not treat financial obligations between unmarried individuals the same way it does when a marriage ends.

Additionally, a court may refuse to enforce a cohabitation agreement if it violates public policy or is deemed unfair. For example, agreements that involve issues of child custody or child support are not enforceable. These matters are always determined based on the best interests of the child, as stated under the allocation of parental responsibilities section of the Illinois Marriage and Dissolution of Marriage Act.

What Are Some Common Reasons for a Cohabitation Agreement in Illinois?

Some common reasons why unmarried couples decide to sign a cohabitation agreement include:

• Clarifying financial responsibilities: The agreement can specify how household expenses, bills, and debts will be divided. The goal is to prevent misunderstandings or conflicts over financial obligations.

• Protecting property ownership: A cohabitation agreement can determine which assets belong to each person. You may find this useful if you already have property when you enter a relationship.

• Defining inheritance rights: Without a legal agreement, you may not automatically inherit property if your partner dies. A cohabitation agreement can protect both of you by outlining inheritance rights.

• Establishing rights upon separation: If the relationship ends, the agreement can outline how property will be divided and provide clear terms that foster realistic expectations.

Are There Disadvantages of Cohabitating Instead of Getting Married?

While cohabiting instead of marrying is a personal choice, there are some risks. One is the lack of automatic legal protection. When you marry, you automatically have rights to your spouse’s property if they die, unless stated otherwise in a will. If you live together without getting married and do not have a cohabitation agreement, you may not have any rights to your partner’s property if they pass away.

Keep in mind that Illinois does not recognize common law marriage. It was abolished under 750 ILCS 5/214 as of 1905. Therefore, even if a couple has lived together for a long time, they do not automatically gain the legal rights of married couples. This makes it even more important for cohabiting individuals to have a written agreement that spells out their rights.

Schedule a Free Consultation With a DuPage County, IL Cohabitation Agreement Attorney Today

If you are thinking about cohabiting in Illinois and want to protect your rights, you should speak with the experienced Wheaton, IL cohabitation agreement lawyers at Andrew Cores Family Law Group. We can help you create an agreement that addresses your needs and follows Illinois law. 

Attorney Andrew Cores, an Illinois Super Lawyer since 2012, offers expert guidance in this area. He is a Fellow for the Collaborative Law Institute of Illinois and has previously served on its TEC Committee. Contact us at 630-871-1002 today for a free consultation to find out how we can help you.