Grounds for Divorce in Illinois: No-Fault, Fault and Separation Requirements
Illinois has one ground for divorce: irreconcilable differences. Six months of living separate and apart makes it irrebuttable, so a spouse cannot block the case, and marital property is divided without regard to marital misconduct.
What are the grounds for divorce in Illinois?
One: irreconcilable differences (750 ILCS 5/401(a)). There are no fault grounds in the section.
| Ground | Section | What the statute says |
|---|---|---|
| Irreconcilable differences | 401(a) | Irreconcilable differences have caused the irretrievable breakdown of the marriage and reconciliation efforts have failed or would be impracticable and not in the family’s best interests |
| Six months apart | 401(a-5) | Living separate and apart for a continuous period of not less than 6 months immediately preceding the judgment is an irrebuttable presumption |
Is Illinois a no-fault state?
Yes. The only ground is irreconcilable differences, so a spouse does not have to prove adultery, cruelty or any other conduct to obtain a divorce.
Is there a separation requirement in Illinois?
Not as a condition of filing. Six months of living separate and apart makes the irreconcilable differences requirement irrebuttably met, and the Illinois divorce timeline calculator shows that date.
Does fault matter to property and maintenance in Illinois?
Not to property: the court divides marital property “without regard to marital misconduct” in just proportions, though it considers dissipation of the marital property (750 ILCS 5/503(d)). Maintenance is decided under section 504 (5/504). See the Illinois property division calculator and the Illinois alimony calculator.
Does fault matter to the children in Illinois?
The court may not consider conduct of a parent that does not affect that parent’s relationship to the child, but it considers the occurrence of abuse against the child or another member of the child’s household as one of the parenting-time factors (750 ILCS 5/602.7(b)-(c)). See the Illinois parenting time calculator.
Can my spouse stop an Illinois divorce?
Not after six months apart. Before then, the court must find irreconcilable differences, but a spouse’s disagreement does not by itself stop the case.
What must the court find about reconciliation in Illinois?
Besides irreconcilable differences, the court must determine that efforts at reconciliation have failed or that future attempts at reconciliation would be impracticable and not in the best interests of the family (401(a)). After six months apart, the presumption makes the first part of the finding automatic.
What must be settled before the judgment in Illinois?
Before a judgment of dissolution, the court must have considered, approved, reserved or made provision for the allocation of parental responsibilities, the support of any child, the maintenance of either spouse and the disposition of property (401(b)). That is why a short ground does not make a short case.
Does dissipation matter in an Illinois divorce?
Yes, to property. Dissipation by a party of the marital property is a factor in dividing it, and a party who claims it must give notice that identifies the period when the marriage began undergoing an irretrievable breakdown, the property and the dates (503(d)). See the Illinois property division calculator.
Is there a separate fault-based procedure in Illinois?
Not in section 401, which lists irreconcilable differences as the ground. Conduct matters elsewhere, such as dissipation in property and abuse in parenting factors, but it is not a ground a spouse has to prove to be divorced.
Do the grounds change the timeline in Illinois?
Only the six-month presumption does: it makes the finding automatic. The 90-day residence rule applies in every case.
Frequently asked questions
What is the ground for divorce in Illinois?
Irreconcilable differences have caused the irretrievable breakdown of the marriage.
Is Illinois a no-fault divorce state?
Yes. Section 401 lists irreconcilable differences as the ground, with no fault grounds.
Is a separation period required for an Illinois divorce?
No, but six months apart makes the ground irrebuttable.
Does adultery matter in an Illinois divorce?
Not to property: marital property is divided without regard to marital misconduct.
Can my spouse contest an Illinois divorce?
Not after six months of living apart.
Official sources
- 750 ILCS 5/401: dissolution of marriage
- 750 ILCS 5/503: disposition of property and debts
- 750 ILCS 5/609.2: parent’s relocation
- 750 ILCS 5/602.7: allocation of parenting time
- 750 ILCS 5/505: child support
- 750 ILCS 5/504: maintenance
A local family law attorney can review your situation — many offer a free consultation.
This is general information, not legal advice. It is based on the cited Illinois statutes, rules and court opinions, and every case turns on its own facts. Confirm how the law applies to your situation with a licensed Illinois attorney.