Divorce in Illinois — the plain-English overview

Illinois rewrote its divorce statute in 2016 — clearing out a lot of older terminology and replacing custody language with new "parental responsibilities" concepts. The rules below shape almost every Illinois divorce today. None of this replaces talking to an Illinois family-law attorney about your specifics, but knowing the starting framework helps you read your own paperwork.

Where you file

Illinois divorces — formally called dissolution of marriage proceedings — are filed in the Circuit Court of the county where either spouse resides. At least one spouse must have been an Illinois resident for 90 days before judgment is entered (750 ILCS 5/401(a)).

Cook County (which contains Chicago) handles a huge share of the state’s divorces and has its own dedicated Domestic Relations Division. Suburban Cook and the collar counties (DuPage, Will, Lake, Kane, McHenry) have their own family-law divisions with their own local rules. Downstate, family cases often share a courtroom with other civil matters.

How long it takes

Illinois is one of the more procedurally fast states for no-fault, uncontested divorces. There is no mandatory statutory waiting period after filing before a final judgment can be entered.

There’s a wrinkle: if the divorce is contested on the grounds of irreconcilable differences, Illinois requires the spouses to have lived separate and apart for at least 6 months before the court will grant the divorce, after which the separation creates an irrebuttable presumption of irreconcilable differences (750 ILCS 5/401). Practically speaking, this matters only when one spouse refuses to acknowledge that the marriage is irretrievably broken — which is rare. Most Illinois divorces never hit the 6-month rule.

Property — what state law assumes

Illinois is an equitable distribution state. The court divides marital property fairly, considering factors including each spouse’s contribution to acquiring and preserving the property, the duration of the marriage, each spouse’s economic circumstances, custodial provisions for any children, and the value of separate property each spouse retains (750 ILCS 5/503).

The line between marital and non-marital property is where Illinois divorces most often get complicated. Pre-marriage assets that grew during the marriage, businesses started before the marriage that expanded during it, and accounts that mixed pre-marital and marital deposits all need careful tracing.

Custody — the starting framework

Illinois retired "custody" in 2016. The framework now is:

• Allocation of parental responsibilities — equivalent to legal custody. The court (or the parents’ agreement) assigns decision-making authority across four specific areas: education, healthcare, religion, and extracurricular activities (750 ILCS 5/602.5). Responsibilities can be joint across all four, split (one parent has education, the other has healthcare, etc.), or sole to one parent.
• Parenting time — equivalent to physical custody / visitation. Set in a parenting plan that lays out the schedule, holidays, transportation, and rules.

Illinois has no statutory presumption in favor of either parent getting more time. The court applies a list of best-interest factors and approves what the parents agree to whenever possible. If the parents can’t agree on a parenting plan within 120 days of filing, the court can appoint a Guardian ad Litem or child representative to investigate and recommend.

Filing fees and fee waivers

Filing fees vary by county. In Cook County, the divorce petition filing fee is approximately $334. The responding spouse’s appearance fee is around $251. Smaller counties tend to charge somewhat less.

If you can’t afford the fees, Illinois has a statewide Application for Waiver of Court Fees (form AOIC SC-FA-1 or the local equivalent) under 735 ILCS 5/5-105. If granted, the court waives the filing fee and other court-imposed costs. The application asks about income, household size, and assets.

What this page can’t tell you

Illinois has 102 counties and 24 judicial circuits, and procedure varies in ways that affect real cases:

• Cook County’s Domestic Relations Division has its own forms, calendars, and pretrial conference procedures that don’t apply downstate.
• Whether your county requires mediation before contested parenting-time hearings (many do; some don’t).
• Whether your court accepts e-filing for self-represented parties (most do now, but the platform and procedure vary).
• How fast judgments actually issue once paperwork is submitted.

The Illinois Courts Self-Help Center (illinoiscourts.gov/self-help) hosts the statewide forms and procedural guides. Your county’s Circuit Clerk is the authoritative source for local rules and fee schedules. For anything strategic — especially around parental responsibilities, business valuations, or maintenance — talk to an Illinois family-law attorney.

Statutes referenced

• Residency & irreconcilable-differences waiting period — 750 ILCS 5/401
• Equitable distribution — 750 ILCS 5/503
• Allocation of parental responsibilities — 750 ILCS 5/602.5
• Parenting time — 750 ILCS 5/602.7
• Court-fee waiver — 735 ILCS 5/5-105

These are the controlling statutes for the facts on this page. State law changes; the linked text always reflects current law.