The Complete Illinois Divorce & Family Law Checklist for 2025

Summary

Case Summary: In re Marriage of Alpert Knight - Core Legal Insight:

In In re Marriage of Alpert Knight (2024 IL App (1st) 230629), the appellate court held that the paying parent's large income increase, well beyond the range the parties' settlement anticipated, was a substantial change in circumstances, and reversed the denial of a motion to increase child support. Income documentation from both the original order date and the present is what made that showing.

Why This Checklist Exists: Preparation matters in Cook County family law cases, and a lack of preparation can affect the outcome of an otherwise strong case. This checklist ensures you don't make those mistakes."

Whether you're facing a high-asset divorce, child custody dispute, or support modification, preparation is everything. This comprehensive Illinois divorce checklist covers every critical step. You'll learn what to do from the moment you decide to file through your final hearing.

30 Days Before Filing: Critical Preparation

Your Illinois divorce preparation begins well before you step into a courtroom. These first steps protect your interests. They also build the foundation for your entire case.

Financial Documentation Gathering

Imagine this scenario: Your spouse claims they earn $75,000 annually. However, you remember seeing bank deposits that suggest otherwise. Without proper documentation, you can't prove it. Start gathering these documents now:

• Gather tax returns: Collect the last 3 years of federal and state tax returns. Include all schedules and W-2s.
• Compile bank statements: Obtain 12 months of statements for all checking, savings, and money market accounts.
• Document investment accounts: Gather statements for brokerage accounts, 401(k)s, IRAs, and pension plans.
• Inventory real estate: Locate deeds, mortgage statements, property tax bills, and recent appraisals.
• List all debts: Credit card statements, auto loans, student loans, and personal loans with current balances.
• Document digital assets: Cryptocurrency wallets, PayPal, Venmo, Zelle accounts, and digital investment platforms.
• Photograph valuable property: Jewelry, art, collectibles, vehicles, and high-value household items.

Digital Security Measures

A common concern: A spouse discovers their partner has been reading their emails for months. Every strategy discussion with their attorney was compromised. Don't let this happen to you.

• Secure sensitive communications: Use encrypted email like ProtonMail or Tutanota for all attorney correspondence.
• Change passwords immediately: Update bank accounts, email, social media, and cloud storage. Use a password manager like 1Password or Bitwarden.
• Enable two-factor authentication: Add 2FA to all financial accounts, email, and social media platforms.
• Screenshot evidence: Capture text messages, emails, and social media posts with visible timestamps. Preserve metadata.
• Back up important files: Store copies of financial documents in secure cloud storage your spouse cannot access.
• Review shared device access: Check for shared Apple IDs, Google accounts, or location-sharing apps.

Personal Preparation Steps

• Open individual accounts: Establish checking and savings accounts in your name only. Choose a different bank than your joint accounts.
• Establish credit independently: Apply for a credit card in your name if you don't have one.
• Secure important documents: Gather birth certificates, passports, Social Security cards, and your marriage certificate.
• Create a support network: Identify trusted friends, family, or a therapist for emotional support.
• Research attorneys: Interview at least 3 Illinois family law attorneys before selecting representation.

At Filing: Required Documents for Illinois Divorce

When you're ready to file your Illinois divorce petition, you'll need specific forms and fees. Requirements vary by county. Always confirm current amounts with your local circuit clerk.

Core Filing Documents

• Petition for Dissolution of Marriage: The primary document that initiates your Illinois divorce case.
• Summons: Official notice to your spouse that divorce proceedings have begun.
• Financial Affidavit: A sworn statement of income, expenses, assets, and liabilities on the single statewide form (750 ILCS 5/501(a)(1)).
• Certificate of Dissolution: Required statistical information for state records.
• Parenting Plan (if children involved): Your proposed allocation of parental responsibilities and parenting time.
• Filing fee payment: Set by each county; confirm the current amount with your circuit clerk. Fee waivers are available for qualifying individuals.

Additional Documents for Specific Situations

• Emergency Motion for Temporary Orders: File this if you need immediate custody, support, or protection orders.
• Order of Protection Petition: Available if domestic violence is a factor. The clerk charges no fee to file it (750 ILCS 60/202(b)).
• Motion for Temporary Maintenance: Request spousal support during proceedings.
• Motion for Temporary Child Support: Request child support while your case is pending.

Discovery Phase: Evidence Collection Under Illinois Law

The discovery phase is where Illinois divorce cases are won or lost. Illinois Supreme Court Rules govern strict deadlines. Missing them can devastate your case.

Responding to Discovery Requests

Consider this example: One spouse failed to respond to interrogatories within the 28-day deadline. The court imposed sanctions. Their credibility was damaged for the rest of the case. Meet every deadline.

• Answer interrogatories within 28 days: These are written questions answered under oath. See Illinois Supreme Court Rule 213.
• Produce requested documents within 28 days: Use secure file transfer. Never use unencrypted email.
• Respond to requests to admit within 28 days: Failure to respond means automatic admission of the facts.
• Prepare for deposition: Meet with your attorney at least 48 hours before testimony.
• Review all responses with attorney: Do this before signing any discovery response.

Conducting Your Own Discovery

• Draft interrogatories: Create written questions about income, assets, debts, and relevant facts.
• Request document production: Ask for tax returns, bank statements, business records, and communications.
• Issue subpoenas if needed: Obtain third-party records from employers, banks, or business partners.
• Schedule depositions: Take sworn testimony from your spouse, witnesses, or experts.
• Retain experts if necessary: Consider forensic accountants, business valuators, custody evaluators, or real estate appraisers.

High-Asset Discovery Considerations

High-net-worth divorces require deeper investigation. Hidden assets are more common than you might think.

• Request trust documentation: Obtain trust agreements, K-1s, distribution records, and beneficiary designations.
• Subpoena business records: If your spouse owns a business, request 3-5 years of financials.
• Demand cryptocurrency disclosures: Request wallet addresses, exchange account statements, and transaction histories.
• Identify hidden assets: Work with a forensic accountant to trace undisclosed accounts.
• Obtain lifestyle analysis: Document your standard of living during marriage. This matters for maintenance calculations.

Cybersecurity Safeguards During Your Illinois Divorce Case

Digital evidence plays an increasingly critical role in Illinois family law cases. Protect yourself while preserving legitimate evidence.

Ongoing Security Protocols

• Enable two-factor authentication: Apply this to all accounts—financial, email, social media, and cloud storage.
• Monitor credit reports weekly: Identity theft and unauthorized accounts are common during divorces. Use AnnualCreditReport.com or a credit monitoring service.
• Use VPN for case documents: Never access sensitive files from public Wi-Fi without protection.
• Avoid social media discussions: Never discuss case details online. All posts are discoverable evidence.
• Document suspicious activity: Screenshot any evidence of your spouse accessing your accounts or tracking your location.
• Secure physical devices: Use passcodes, biometric locks, and encrypted storage on phones and computers.

Evidence Preservation Guidelines

• Do not delete anything: Destroying evidence can result in sanctions and adverse inferences.
• Preserve text messages properly: Use forensic backup tools, not just screenshots.
• Maintain email archives: Export important emails to PDF with full headers.
• Document chain of custody: Record when and how you obtained each piece of evidence.
• Consult attorney before accessing: Never access your spouse's accounts, devices, or private communications without legal guidance.

Child Custody Preparation Checklist

If children are involved in your Illinois divorce, custody requires specific preparation. Illinois now calls this "allocation of parental responsibilities."

Documentation for Custody Cases

• Create parenting history log: Document who handles daily care, school activities, and medical appointments.
• Gather school records: Collect report cards, attendance records, teacher communications, and IEP/504 plans.
• Compile medical records: Include pediatrician visits, specialist appointments, immunization records, and therapy notes.
• Document extracurricular involvement: Note who registers children, transports them, attends events, and pays fees.
• Preserve communication records: Save co-parenting app messages, texts, and emails about your children.
• Identify witnesses: List teachers, coaches, doctors, and family members who can speak to your parenting involvement.

Parenting Plan Considerations

• Draft proposed parenting schedule: Include regular schedule, holidays, summer, and school breaks.
• Address decision-making allocation: Cover education, healthcare, religion, and extracurricular activities.
• Include communication provisions: Specify phone/video calls and access to school/medical information.
• Plan for transportation: Determine who transports, exchange locations, and how costs are split.
• Consider right of first refusal: Address what happens when alternative childcare is needed.
• Address relocation provisions: Include notice requirements and distance limitations.

child support modification Checklist

If you're seeking to modify an existing Illinois child support order, you must document the substantial change in circumstances thoroughly. In In re Marriage of Alpert Knight (2024 IL App (1st) 230629), the mother's comparison of the father's income at judgment with his much higher later income was enough to show a substantial change on appeal.

Proving Changed Circumstances

• Gather income documentation: Compare current

References

• Illinois Supreme Court Rules: https://www.illinoiscourts.gov/supremecourt/rules/
• Illinois Department of Children and Family Services - Parenting Plans: https://www2.illinois.gov/dcfs/aboutus/pages/parentingplans.aspx
• American Bar Association - Family Law: https://www.americanbar.org/groups/family_law/
• Illinois State Bar Association - Divorce (Dissolution of Marriage): https://www.isba.org/

Written by Jonathan D. Steele

Chicago divorce attorney with cybersecurity certifications (Security+, ISC2 CC, Google Cybersecurity Professional Certificate). Illinois Super Lawyers Rising Star 2016-2025.

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For more insights, read our Divorce Decoded blog.