Divorce in Illinois: Costs, Laws, and Calculators (2026)

Everything you need to understand the financial reality of divorce in Illinois. State-specific costs, formulas, and free calculators.

Avg. uncontested
$2,000 - $5,500
Avg. contested
$13,000 - $45,000
Typical timeline
4 - 14 months
DCE State Score
64 / 100

Illinois divorces typically cost 28% less than the national average of $12,900.

Illinois uses a statutory maintenance formula and requires marriage length of at least 5 years for guideline support.

Illinois is a no-fault only state. The only ground for dissolution is "irreconcilable differences." The state uses a maintenance formula based on the income difference between spouses and a duration multiplier tied to marriage length, which provides more predictability than purely discretionary states. Illinois courts apply the "best interests of the child" standard without a statutory presumption of equal time, giving judges significant discretion in custody matters. Cook County (Chicago) has heavily congested courts, particularly for contested cases, and attorney rates in Chicago run significantly higher than downstate.

Key Fact

Illinois maintenance duration formula: for a 10-year marriage, maintenance lasts approximately 4 years; for 20 years, approximately 10 years, scaling based on a statutory multiplier table.

Recent Development

Illinois enacted significant changes to its income shares child support model in recent years, aligning more closely with actual expenditure data for families at different income levels.

Illinois Divorce Quick Facts

Verified statutory data, attorney rates, and procedural rules for Illinois.

Property division system
Equitable Distribution (judicial discretion)
Alimony formula type
Statutory Formula
Child support formula
Income Shares Model
Mandatory waiting period
None
Residency requirement
90 days
Mediation required
No
Equal parenting presumption
No
Fault divorce available
No
Collaborative divorce available
Yes
Filing fee range
$289 - $388
Attorney hourly rates
$250 - $500/hour
Data last verified
January 1, 2025

DCE State Score Breakdown

Our proprietary index ranks every state on cost, complexity, and timeline. Higher is more favorable.

Overall DCE State Score

64/ 100

A score of 64 means Illinois is roughly average in terms of divorce cost and complexity.

Cost Score

24/ 40

Based on filing fees, attorney rates, and total typical costs in Illinois.

Complexity Score

30/ 30

Reflects judicial discretion, mandatory mediation, and procedural hurdles.

Timeline Score

10/ 30

Driven by waiting periods and average case duration from filing to decree.

Divorce Calculators for Illinois

All 15 calculators preconfigured with Illinois statutory data.

Illinois Divorce Laws Overview

Property Division

Illinois uses equitable distribution to divide marital property. This does not mean equal, it means fair, based on the circumstances. Judges consider factors including each spouse's income and earning capacity, contributions to the marriage, length of the marriage, and the economic circumstances of each spouse. Outcomes can vary significantly from case to case.

Spousal Support (Alimony)

Illinois uses a statutory formula to calculate alimony, which makes spousal support more predictable than in purely discretionary states. The formula typically considers the income difference between spouses and the length of the marriage. Courts have limited discretion to deviate from the formula without documented justification.

Child Support

Illinois uses the Income Shares Model for child support. Both parents' gross incomes are combined, the total support obligation is determined from a guideline table, and each parent's share is proportional to their share of the combined income. The paying parent pays their share to the receiving parent.

Custody and Parenting Time

Illinois courts determine custody based on the best interests of the child. While there is no statutory presumption of equal time, courts generally favor arrangements that allow both parents meaningful involvement in the child's life.

This estimate is for planning purposes only and does not constitute legal or financial advice. Consult a licensed family law attorney in your state for guidance specific to your situation.

Recent Law Changes in Illinois

All state updates

Notable updates to Illinois family law that affect divorce outcomes and costs.

Illinois Continues to Refine Maintenance Formula Application

Moderate

Effective January 2023

Illinois couples with combined income near or above the statutory threshold should expect outcomes to depend more on judicial discretion. Documenting marital standard of living and each spouse's earning trajectory is increasingly important for predictable awards.

Frequently Asked Questions

How much does a divorce cost in Illinois?
An uncontested divorce in Illinois typically costs $2,000 - $5,500. Contested cases run $13,000 - $45,000, depending on attorney involvement, custody disputes, and the complexity of the marital estate. Court filing fees alone are $289 - $388.
How long does a divorce take in Illinois?
Illinois requires a 0-day waiting period after filing. Uncontested cases finalize in roughly 4 months on average, while contested cases take about 14 months from filing to final decree.
How is property divided in Illinois?
Illinois uses equitable distribution. Marital assets are divided based on what the court considers fair, not necessarily equal. Judges weigh income, contributions, length of marriage, and the economic circumstances of each spouse.
How is child support calculated in Illinois?
Illinois uses the Income Shares Model. Illinois uses the Income Shares Model for child support. Both parents' gross incomes are combined, the total support obligation is determined from a guideline table, and each parent's share is proportional to their share of the combined income. The paying parent pays their share to the receiving parent.
How is alimony determined in Illinois?
Illinois alimony follows a statutory formula approach. Illinois uses a statutory formula to calculate alimony, which makes spousal support more predictable than in purely discretionary states. The formula typically considers the income difference between spouses and the length of the marriage. Courts have limited discretion to deviate from the formula without documented justification.

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