A clearer Illinois Family Law & Divorce page: property timeline, support records, and before the record drifts

Illinois reformed its divorce law significantly in 2016 through Public Act 99-0090, which eliminated all fault-based grounds for divorce and replaced them with a single no-fault ground: irreconcilable differences. The same legislation replaced the terms "custody" and "visitation" with "allocation of parental responsibilities" and "parenting time," reflecting a more child-centered framework. Illinois is an equitable distribution state for property division, and the law provides structured frameworks for both spousal maintenance (formerly "alimony") and child support.

No-Fault Divorce: Irreconcilable Differences

Under 750 ILCS 5/401, the sole ground for divorce in Illinois is irreconcilable differences — the marriage has irretrievably broken down and efforts at reconciliation would be impractical and not in the best interests of the family. If both spouses agree the marriage is irretrievably broken, a divorce can proceed without any waiting period. If one spouse contests the irreconcilable differences ground, there is a rebuttable presumption: if the spouses have lived separate and apart for at least 6 months, the court presumes irreconcilable differences exist. The 6-month separation creates an automatic presumption — but the divorce can proceed faster if both parties agree.

Equitable Distribution of Marital Property

Under 750 ILCS 5/503, marital property is divided equitably — fairly but not necessarily 50/50. Illinois courts consider: each spouse's contribution to acquisition of marital property; the value of property assigned to each spouse; the parties' economic circumstances; duration of the marriage; obligations from prior marriages; tax consequences; whether one parent will be the primary caregiver; dissipation of assets; and other relevant factors. Separate property (pre-marital property, gifts, inheritances) is not subject to division but can be lost through commingling. Illinois courts are not required to start from a 50/50 split; they are required to reach a fair result based on all factors, which in many cases results in roughly equal division for long marriages but can be quite unequal for short marriages or where one spouse was primarily responsible for building wealth.

Allocation of Parental Responsibilities

Illinois's 2016 reform replaced "legal custody" and "physical custody" with "allocation of parental responsibilities" and "parenting time." Parental responsibilities are allocated based on the best interest of the child (750 ILCS 5/602.5), considering: each parent's wishes; the child's wishes (given appropriate weight by age); the child's adjustment to home, school, and community; the mental and physical health of all parties; domestic violence; the child's relationship with each parent; and willingness to facilitate the child's relationship with the other parent. "Significant decision-making responsibilities" (formerly legal custody) can be allocated jointly or to one parent for decisions about education, health care, religion, and extracurricular activities. Courts can — and frequently do — allocate different decision categories differently between parents.

Illinois Child Support: Income Shares Model

Illinois uses the Income Shares Model for child support (750 ILCS 5/505). Both parents' net incomes are combined; the child support obligation is calculated based on that combined income using statutory guidelines tables; and each parent contributes proportionally to their share of combined income. The non-primary caregiver parent (the one with less parenting time) typically pays the proportional share to the primary caregiver. When parenting time is more equally shared, the calculation adjusts to account for the direct expenses each parent incurs while caring for the child. Illinois guidelines tables are published by IDHFS and updated periodically. Child support in Illinois also includes add-ons for health insurance, work-related childcare, and extraordinary medical expenses.

Illinois Spousal Maintenance (Formerly Alimony)

Illinois provides a formula for maintenance in cases where combined gross income is under $500,000 and there is no reason to deviate from the formula (750 ILCS 5/504(b-1)): annual maintenance = (33⅓% of payor's net income) minus (25% of payee's net income), provided the maintenance amount does not exceed 40% of the combined net income. Duration guidelines: multiply the length of the marriage by a factor (e.g., 0.20 for 5-year marriages, 0.32 for 10-year marriages, 0.44 for 15-year marriages, through permanent maintenance for marriages of 20+ years). Maintenance terminates on the death of either party, the payee's remarriage, or a court finding of cohabitation with a romantic partner on a resident basis.