Divorce in Illinois (2026)

Illinois as a Pure No-Fault Divorce State

Illinois stands out nationally as one of a relatively small number of states that have completely abolished fault-based divorce. Since January 1, 2016, when sweeping amendments to the Illinois Marriage and Dissolution of Marriage Act (IMDMA) took effect, the only ground for divorce in Illinois is irreconcilable differences that have caused the irretrievable breakdown of the marriage (750 ILCS 5/401).

Before 2016, Illinois recognized multiple fault grounds including adultery, habitual drunkenness, mental cruelty, and physical cruelty. The legislature eliminated all of these, concluding that fault-based litigation increased costs, delayed proceedings, and harmed families without improving outcomes. Illinois joined a growing trend among states that have determined the adversarial process of proving fault does not serve the interests of divorcing families.

This means that neither spouse can raise the other’s misconduct as a basis for the divorce itself. A spouse’s behavior during the marriage may still be relevant in limited contexts, such as the dissipation of marital assets, but it cannot form the basis of the divorce petition. The sole question is whether the marriage has broken down irretrievably, and if the parties have lived separate and apart for at least six months, that breakdown is presumed. Importantly, “separate and apart” does not require living in different residences; spouses may live under the same roof while leading separate lives, and that period still counts toward the six-month requirement.

Residency and Filing Requirements

To file for divorce in Illinois, at least one spouse must have been a resident of the state for a minimum of 90 days before the petition is filed. There is no separate county residency requirement, making Illinois one of the more accessible states for filing. The case is typically filed in the circuit court of the county where either spouse resides.

If both spouses agree that the marriage is irretrievably broken, the court may waive the six-month separation period. When the parties do not agree, the six-month separation requirement serves as evidence that efforts at reconciliation have failed.

Equitable Distribution: How Illinois Divides Assets

Illinois follows the equitable distribution model. The court divides marital property in proportions it deems just, considering a list of statutory factors rather than defaulting to a fifty-fifty split. Relevant factors include:

• Each spouse’s contribution to the acquisition, preservation, or increase in value of marital property
• The duration of the marriage
• The economic circumstances of each spouse at the time of division
• Any prior obligations from a previous marriage
• Whether property was acquired before or during the marriage
• The age, health, and employability of each party

Non-marital property, such as assets owned before the marriage, inheritances, and gifts directed to one spouse, is generally not subject to division unless it has been commingled with marital assets.

Spousal Support (Maintenance)

Illinois uses a statutory formula for calculating maintenance when the combined gross income of both spouses is under a specified threshold (currently $500,000). The formula sets both the amount and the duration of maintenance based on the length of the marriage. For marriages of twenty years or more, the court may award indefinite maintenance.

Courts may deviate from the formula in cases involving significant disparity in income, advanced age, or other circumstances that make a formulaic result unjust. The goal of maintenance is to allow the lower-earning spouse to maintain a reasonable standard of living while transitioning toward financial independence.

The Illinois Divorce Process

1. Filing the Petition — One spouse files a Petition for Dissolution of Marriage with the circuit court and pays the filing fee.
2. Service of Process — The petition must be served on the other spouse, who then has thirty days to file an appearance and response.
3. Financial Disclosures — Both parties are required to exchange financial affidavits disclosing income, expenses, assets, and liabilities.
4. Parenting Plan (if applicable) — When children are involved, the parties must submit a proposed parenting plan or attend mediation to develop one.
5. Negotiation or Mediation — Most Illinois divorces settle through negotiation or mediation. Courts in many counties require mediation for custody and parenting disputes.
6. Trial (if needed) — If the parties cannot agree, a judge will hear evidence and decide contested issues at trial.
7. Judgment for Dissolution — Once all matters are resolved, the court enters a Judgment for Dissolution of Marriage.

When to Consult an Attorney

Although Illinois allows pro se filing, the IMDMA’s provisions on property classification, maintenance calculations, and parenting allocations involve significant complexity. Legal representation is strongly recommended when the marriage involves substantial assets, business ownership, disputes over parenting time, or situations where one spouse has significantly more financial knowledge or power than the other. An experienced Illinois family law attorney can ensure that your rights are protected and that financial disclosures are thorough and accurate.

Frequently Asked Questions

What are the residency requirements for an Illinois divorce?

At least one spouse must have been a resident of Illinois for a minimum of 90 days before filing. There is no separate county residency requirement. The spouses must have lived separate and apart for at least six months (though living under the same roof can qualify), or the six-month separation period may be waived if both spouses agree the marriage is irretrievably broken.

Is Illinois a community property or equitable distribution state?

Illinois follows equitable distribution. The court divides marital property in proportions it deems just, considering each spouse’s contributions, the duration of the marriage, economic circumstances, age, health, and employability. Non-marital property (pre-marriage assets, inheritances, gifts) is generally not subject to division unless commingled.

Is Illinois a no-fault divorce state?

Yes. Since January 2016, Illinois is exclusively no-fault. All fault-based grounds were eliminated, and the only standard is irreconcilable differences that have caused the irretrievable breakdown of the marriage. Neither spouse needs to prove misconduct.

How does Illinois calculate spousal maintenance?

Illinois uses a statutory formula under 750 ILCS 5/504 when combined gross income is under $500,000. The formula sets both the amount (33.33% of the payor’s net income minus 25% of the payee’s, capped so the payee does not exceed 40% of combined net income) and the duration (tied to marriage length by statutory multiplier, with indefinite maintenance possible for marriages of 20+ years).

Can I file a fault-based divorce in Illinois?

No. Since the 2016 amendments to the IMDMA, Illinois has eliminated all fault-based grounds for divorce. The only recognized ground is irreconcilable differences causing the irretrievable breakdown of the marriage under 750 ILCS 5/401. While you cannot file on fault grounds, a spouse’s misconduct may still be relevant in certain financial matters, such as claims of dissipation of marital assets under 750 ILCS 5/503(d)(2).

What happens if my spouse and I agree on everything?

If both spouses agree on all issues, including property division, support, and parenting arrangements (if applicable), the divorce can proceed as an uncontested matter. Both parties can waive the six-month separation requirement, and many agreed divorces in Illinois are finalized within two to four months. The court will review the agreement to confirm it is fair and, if children are involved, that the parenting plan serves the children’s best interests.

How This Guide Was Researched

This guide was developed through a detailed review of the Illinois Marriage and Dissolution of Marriage Act (750 ILCS 5/), with particular attention to the 2016 amendments that transformed Illinois into a purely no-fault divorce state. Property division rules were verified against 750 ILCS 5/503, and the maintenance formula was confirmed against 750 ILCS 5/504 and the statutory duration multipliers in Section 504(b-1). Filing procedures and fee information were cross-referenced with the Illinois Courts self-help portal and approved standardized divorce forms published by the Administrative Office of the Illinois Courts.

Sources and Legal References

This guide draws on the following Illinois statutes and official resources:

• 750 ILCS 5/401 — Dissolution of marriage; irreconcilable differences as the sole ground for divorce
• 750 ILCS 5/503 — Disposition of property and debts; equitable distribution framework and factors
• 750 ILCS 5/504 — Maintenance (alimony); statutory formula for amount and duration
• 750 ILCS 5/505 — Child support; income shares model and guideline calculations
• 750 ILCS 5/602.5 through 602.7 — Allocation of parental responsibilities and parenting time

Official Illinois Resources

• Illinois Courts — Self-Help
• Illinois Courts — Family Law Resources
• Illinois Divorce, Child Support & Maintenance Forms

For more about how we research our guides, see our editorial policy and sources methodology.

Related Guides

Illinois Divorce Guides

• Dividing Retirement Accounts in an Illinois Divorce
• Illinois Parenting Time Schedules

Other Illinois Family Law Guides

• Child Custody in Illinois
• Child Support and Alimony in Illinois

National Guides

• Contested vs. Uncontested Divorce
• Divorce Mediation vs. Litigation
• Complete Guide to Divorce
• Divorce Checklist