The divorce process in Illinois starts with a 90-day residency requirement and ends with a judge signing a Judgment of Dissolution of Marriage. In between, you file a petition citing irreconcilable differences, serve your spouse, exchange financial information, and resolve property division, support, and parenting arrangements either by agreement or at trial. Uncontested cases can finish in a few months. Contested ones often run past a year.
Who Can File and on What Grounds
At least one spouse must have lived in Illinois for 90 consecutive days before the petition is filed or before the court enters the final judgment.1Illinois General Assembly. Illinois Code 750 ILCS 5/401 – Dissolution of Marriage Active-duty time stationed in Illinois counts. You file in the circuit court of the county where either spouse lives.
Illinois is a no-fault state. The only recognized ground is irreconcilable differences, and the court does not investigate who caused the breakdown. If you and your spouse have lived separate and apart for at least six continuous months before the judgment is entered, the law treats that as conclusive proof that irreconcilable differences exist, and your spouse cannot contest it.2Illinois General Assembly. Illinois Code 750 ILCS 5 – Illinois Marriage and Dissolution of Marriage Act You can be “separate and apart” while still living under one roof if the marital relationship has genuinely ended.
A Faster Track for Couples Who Qualify
If your marriage was short, your finances are simple, and you have no children, you may qualify for joint simplified dissolution. Both spouses file together and skip most of the discovery and litigation a standard case involves. Every one of these conditions must be met at filing:3Illinois General Assembly. Illinois Code 750 ILCS 5/452 – Joint Simplified Dissolution
- No children were born or adopted during the marriage, and the wife is not pregnant.
- The marriage lasted eight years or less.
- Total marital property, after subtracting debts, is worth less than $50,000. Neither spouse owns real estate or retirement benefits, except IRAs with a combined value under $10,000.
- Combined gross annual income is under $60,000, and neither spouse individually earns more than $30,000.
- Neither spouse seeks maintenance.
- You already have a written agreement dividing all assets worth more than $100 and allocating debts.
Miss any one of those thresholds and you use the standard process described below.
Filing the Petition and Financial Affidavit
The case opens with a Petition for Dissolution of Marriage. It names both spouses, states where and when you married, and lists any minor children.4Illinois Courts. Petition for Divorce – Divorce No Children Under 18 There is a separate petition form for cases involving children under 18. You also prepare a Summons, which is how the court formally notifies your spouse. Standardized versions of these forms are posted on the Illinois Courts website.5Office of the Illinois Courts. Divorce, Child Support, and Maintenance
Both spouses must complete a Financial Affidavit, a Supreme Court-approved form required in every Illinois circuit court.6Illinois Courts. Financial Affidavit – Family and Divorce It covers every income source, your monthly expenses, and a full inventory of assets and debts, with supporting pay stubs, tax returns, and bank statements attached when you have them. Cases involving children require supplemental forms covering child support calculations and health insurance.7Office of the Illinois Courts. Financial Affidavit Treat this document carefully. Intentionally or recklessly entering inaccurate or misleading information can bring significant penalties and sanctions, including an order to pay the other side’s attorney fees.
Illinois requires all civil filings to go through the statewide eFileIL system using an approved Electronic Filing Service Provider. You cannot bring paper into the clerk’s office.8Office of the Illinois Courts. Circuit Court E-Filing Filing fees vary by county and typically run into the hundreds of dollars. If you cannot afford the fee, you can submit an Application for Waiver of Court Fees through the same system.9Office of the Illinois Courts. Supreme Court Fee Waiver
Serving Your Spouse
After the court accepts your filing, your spouse must be formally served with the petition and summons. You have a few options:
- Hire the county sheriff to hand-deliver the documents. Fees vary by county, typically under $100, sometimes plus mileage.
- Use a licensed private process server, which can help when the sheriff’s office has limited hours or your spouse is hard to track down.
- Ask your spouse to sign an Entry of Appearance acknowledging receipt, which eliminates the need for formal service when they cooperate.
If your spouse cannot be located after a genuine search, Illinois allows service by publication. You file an affidavit explaining your diligent inquiry, and notice is published in a newspaper in the county where the case is pending. Within 10 days of the first publication, the clerk mails a copy to the last known address.10Illinois General Assembly. Illinois Code 735 ILCS 5/2-206 – Service by Publication Courts scrutinize whether you genuinely tried other methods first.
Getting Support or Protection While the Case Is Pending
Divorce cases often take months, and you can ask the court for interim orders under 750 ILCS 5/501. The court decides these requests on a summary basis, relying mainly on financial affidavits rather than a full evidentiary hearing.11Illinois General Assembly. Illinois Code 750 ILCS 5/501 – Temporary Relief Available relief includes:
- Temporary maintenance or child support so neither spouse goes without basic financial support during the case.
- Restraining orders stopping either spouse from transferring, hiding, or disposing of property outside the normal course of daily life.
- Orders prohibiting a parent from removing a child from the court’s jurisdiction for more than 14 days.
- Orders prohibiting a spouse from striking or interfering with the personal liberty of the other spouse or any child.
If one spouse needs a lawyer but cannot afford one, the court can award interim attorney fees. These awards do not lock in who ultimately pays legal costs; the final judgment can reallocate them.11Illinois General Assembly. Illinois Code 750 ILCS 5/501 – Temporary Relief
What Gets Decided Before Judgment
Property and Debts
Illinois is an equitable distribution state. The court divides marital property fairly, which is not necessarily 50/50. Marital property includes almost everything either spouse acquired during the marriage, including debts. Non-marital property is set aside and returned to the owning spouse.12Illinois General Assembly. Illinois Code 750 ILCS 5/503 – Disposition of Property and Debts The main non-marital categories are property owned before the marriage, gifts or inheritances received by one spouse, property excluded by a valid prenuptial or postnuptial agreement, property acquired after a judgment of legal separation, and the increase in value of non-marital property.
Judges weigh statutory factors including each spouse’s contribution to acquiring or preserving property (contributions as a homemaker count), each spouse’s economic circumstances, the length of the marriage, and whether either spouse wasted marital assets, which the statute calls dissipation. A dissipation claim requires a notice of intent filed at least 60 days before trial.12Illinois General Assembly. Illinois Code 750 ILCS 5/503 – Disposition of Property and Debts
Retirement accounts need extra care. Dividing them usually requires a Qualified Illinois Domestic Relations Order (QILDRO) for state pensions or a federal Qualified Domestic Relations Order (QDRO) for private plans like 401(k)s. A badly drafted order can mean losing retirement money permanently.
Spousal Maintenance
Maintenance is not automatic. The court first decides whether a spouse qualifies, then applies a statutory formula when the couple’s combined net annual income is $500,000 or less. The monthly payment equals 33.33% of the paying spouse’s net income minus 25% of the receiving spouse’s net income, capped so the receiving spouse’s total income after maintenance does not exceed 40% of the couple’s combined net income.13Illinois General Assembly. Illinois Code 750 ILCS 5/504 – Maintenance
Duration is set by multiplying the length of the marriage by a statutory factor that grows with the length of the marriage. A 10-year marriage, for example, uses a 44% multiplier, producing roughly 4.4 years of maintenance. At 20 years or more, the court may order maintenance for a period equal to the marriage length or order it indefinitely. When combined income is above $500,000, the court has discretion to set maintenance without following the formula.13Illinois General Assembly. Illinois Code 750 ILCS 5/504 – Maintenance
Child Support
Illinois uses an income shares model that approximates what both parents would have spent on the children if they still lived together. Each parent’s net income is calculated and combined, the basic support obligation is pulled from a schedule published by the Illinois Department of Healthcare and Family Services based on combined income and number of children, and the obligation is split proportionally. When one parent has 146 or more overnight stays per year, the formula shifts to account for shared physical care. Childcare, health insurance premiums, and uninsured medical expenses are divided in proportion to income.14Illinois General Assembly. Illinois Code 750 ILCS 5/505 – Child Support The guidelines carry a rebuttable presumption, so the calculated amount stands unless the court finds it inappropriate after considering factors like special medical needs or extraordinary educational expenses.
Parenting Time and Decision-Making
Illinois no longer uses the words custody and visitation. The law allocates parenting time (the schedule of when each parent has the children) and significant decision-making responsibilities (who decides education, healthcare, and religious upbringing). Both are governed by the best interests of the child.15Illinois General Assembly. Illinois Code 750 ILCS 5/602.7 – Best Interests of Child
Parents must file a Parenting Plan covering, at minimum, how significant decisions will be allocated and the parenting time schedule. If parents cannot agree, the court orders mediation unless impediments like a history of domestic violence make mediation inappropriate. An agreement reached in mediation becomes a binding court order once entered.16Illinois General Assembly. Illinois Code 750 ILCS 5/602.10 – Parenting Plan A right-of-first-refusal clause, which requires the parent who has the children to offer the other parent the chance to step in before using a third-party caregiver, is not automatic and has to be negotiated into the plan.
Discovery and Settlement
After the initial filings, both sides exchange information through discovery. This goes beyond the Financial Affidavit and can include credit card statements, property appraisals, and business valuations. When one spouse owns a business or holds complex investments, discovery can stretch for months and may require appraisers or forensic accountants.
Most Illinois divorces settle. The settlement takes the form of a Marital Settlement Agreement (MSA), a detailed contract covering bank accounts, real estate, retirement funds, debts, and maintenance. When children are involved, the Parenting Plan is filed alongside the MSA. Both become enforceable court orders once the judge approves them. Issues that cannot be settled go to trial, where a judge hears evidence and applies the statutory factors. Trials are expensive, which is why even high-conflict cases often settle on most issues and litigate only the sticking points.
The Prove-Up Hearing and Final Judgment
Once every issue is resolved, by agreement or by trial, the case moves to a prove-up hearing. This is a brief court appearance where the petitioner testifies to confirm the marriage, residency, the breakdown of the relationship, and the terms of the settlement. The judge reviews the MSA and Parenting Plan to confirm they are fair and consistent with Illinois law.2Illinois General Assembly. Illinois Code 750 ILCS 5 – Illinois Marriage and Dissolution of Marriage Act If satisfied, the judge signs the Judgment of Dissolution of Marriage, which officially ends the marriage.
Either party has 30 days after judgment to file a post-trial motion asking the court to reconsider or modify its ruling.17Illinois General Assembly. Illinois Code 735 ILCS 5/2-1202 – Post-Trial Motions After that window closes, or once any motion is resolved, the judgment is final. If a spouse received a default judgment because they never responded, the same 30-day deadline applies for a motion to vacate, and the odds of overturning a default drop sharply after that.