Civil Unions in Illinois

What a civil union is in Illinois

A civil union is a legal relationship between two people, of either the same or opposite sex, established under the Illinois Religious Freedom Protection and Civil Union Act (750 ILCS 75/10). The Act took effect on June 1, 2011, and it still provides for civil union licenses today.

The steps look much like getting married:

• Both partners complete and sign an application, pay the fees and appear before the county clerk, who issues a license and a certificate of civil union once satisfied that the civil union is not prohibited (750 ILCS 75/30(c)).
• The license becomes effective in the county where it was issued one day after it is issued, and it expires 60 days after it becomes effective (75/30(d)).
• The civil union may be certified by, among others, a judge, a county clerk in counties with 2,000,000 or more inhabitants, a public official who can solemnize marriages, or under the practices of a religious denomination. The person who performs it sends the certificate to the county clerk within 10 days (750 ILCS 75/40).

Some civil unions are prohibited, including one entered before both partners turn 18, one entered before an earlier marriage, civil union or similar relationship of either partner is dissolved, and one between close relatives or first cousins (750 ILCS 75/25). Religious bodies are free to choose whether to solemnize or officiate a civil union (75/15).

Rights and duties of civil union partners

A party to a civil union is entitled to the same legal obligations, responsibilities, protections and benefits that the law of Illinois gives to spouses, whether they come from statute, administrative rule, policy, common law or any other source of civil or criminal law (750 ILCS 75/20).

The definitions section adds to that. Since the Act took effect in 2011, it has said that a party to a civil union is included in any definition or use of terms such as "spouse," "family" and "next of kin." Since January 1, 2026, the list also includes "marriage," "married," "husband" and "wife," and the rule applies whether the partners are of the same sex or different sexes (750 ILCS 75/10, as amended by Public Act 104-40). In plain terms, when an Illinois law speaks about spouses, it generally includes civil union partners too.

That equal treatment comes with the duties of a marriage, not only the benefits. It also means ending the relationship takes a court case, just as a divorce does. If you have children, read our guide to the Illinois Parentage Act of 2015, which explains how parentage is established.

Civil union vs. marriage in Illinois

Under Illinois law, a civil union and a marriage carry the same legal obligations, responsibilities, protections and benefits. The differences are mostly practical.

• Who can choose it. Illinois marriage law speaks of a marriage between 2 persons (750 ILCS 5/201), and a civil union is open to couples of the same or opposite sex, so many couples can choose either one.
• Paperwork. A civil union has its own application, license and certificate (75/30).
• Outside Illinois. Section 20 is a rule of Illinois law. Federal agencies and other states apply their own rules, so a civil union may not be treated as a marriage for every federal or out-of-state purpose. Check with the agency involved, or a tax professional, before you rely on a civil union for a federal benefit or a tax filing.

Couples who live together without a marriage or civil union should read our guide to common law marriage in Illinois.

Converting a civil union to a marriage

Yes, you can turn a civil union into a marriage. Parties to a civil union may apply for and receive a marriage license and have the marriage solemnized and registered, as long as they are otherwise eligible to marry and are the same two people who are in the civil union. The fee for the marriage license application is waived (750 ILCS 75/65(a)).

Once the partners marry, as of the date stated on the marriage certificate, they are no longer considered to be in a civil union but are in a legal marriage (75/65(c)). The statute also had a one-year window after June 1, 2014, when couples could have a civil union designated and recorded as a marriage, effective on the date of the civil union, by signing and returning a marriage certificate (75/65(b)). That window has closed, so today the path is a new marriage license.

You do not need to dissolve the civil union first; Section 65 lets the same two partners marry while they are in the civil union. If you are thinking about converting while a dissolution case is pending, talk with a lawyer before you act.

Civil unions and domestic partnerships from other states

Illinois recognizes a civil union from another state, and a substantially similar legal relationship other than a common law marriage, as a civil union, if it was legally entered into there (750 ILCS 75/60). A registered domestic partnership from another state can qualify if it is substantially similar; ask a lawyer to compare it.

Marriages from other places are treated as marriages. A marriage legally entered into in another jurisdiction, whether of the same sex or different sexes, is recognized in Illinois as a marriage, as long as it is not a common law marriage (75/60).

How to dissolve a civil union in Illinois

A civil union ends through a court case for dissolution of the civil union, using the same grounds and procedures as a divorce.

Grounds and procedure

A court enters a judgment of dissolution of a civil union if, when the case begins, it meets the grounds for dissolution in Section 401 of the Illinois Marriage and Dissolution of Marriage Act, and Sections 401 through 413 of that Act apply (750 ILCS 75/45). The Section 401 ground is irreconcilable differences that have caused an irretrievable breakdown, after efforts at reconciliation have failed or would be impracticable. One partner must also have lived in Illinois, or been stationed here in the armed services, for 90 days (750 ILCS 5/401(a)). Living separate and apart for at least six continuous months before the judgment creates an irrebuttable presumption that the ground is met (401(a-5)).

Section 45 also says that anyone who enters a civil union in Illinois consents to the jurisdiction of Illinois courts for any action relating to it, even if one or both partners later leave the state. Because the Section 401 grounds include the residence rule, ask a lawyer how these two rules fit your facts if neither of you lives in Illinois now. A civil union can also be declared invalid under Sections 301 through 306 of that Act, the rules for declaring a marriage invalid (75/45); see our annulment page.

In Cook County, the Domestic Relations Division hears dissolution of civil unions and invalidity of civil unions. The case starts with a petition; see the petition for dissolution.

Property, support and children

The same issues come up as in a divorce. The maintenance statute names dissolution of a civil union directly (750 ILCS 5/504(a)), and through Sections 10 and 20 of the Civil Union Act, the rules written for spouses on property, support and parenting generally apply to civil union partners as well. Cook County's financial disclosure rule expressly covers cases about the disposition of property in a civil union (Cook County Circuit Court Rule 13.3.1(a)). For an overview of these rules, read our guide to the Illinois Marriage and Dissolution of Marriage Act.

Getting help

The firm can explain how the law applies to your civil union, help with an agreed dissolution, or represent you in a contested case. Chicago Family Attorneys handles family law only, for clients in Chicago and Cook, DuPage, Lake and Will Counties, from its office in Chicago.

Published fees include an uncontested divorce at a $1,500 flat fee (court filing fees not included). Full representation is an initial payment of $1,500 to $2,500, then $500 to $650 per month beginning 30 days after the initial payment while representation remains active. Ask which service fits an agreed civil union dissolution. Fees are confirmed in writing before you engage the firm, and no lawyer can promise a particular result.

Consultations are by phone; a free weekend consultation is available by Zoom. Call 312-965-5618, or visit our LGBTQ family law and Chicago divorce attorneys pages.