AlimonyCalcByState
🏙️ IL Pre-Filled
Illinois Spousal Maintenance Calculator 2026
Estimate spousal support payments in Illinois based on both incomes and marriage length. Illinois laws are already loaded.
Spousal Maintenance
Term Used in IL
Statutory Formula
Calculation Type
Yes
Permanent Available
No-Fault
Fault Considered
Estimate Only: This calculator provides a general estimate. Illinois spousal maintenance is calculated by formula but still subject to judicial discretion. Consult a family law attorney for advice specific to your situation.
⚖️ Illinois Spousal Maintenance Calculator
Illinois Spousal Maintenance Estimator
Enter both spouses’ monthly gross incomes and marriage length — Illinois’s approach is pre-loaded.
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Est. Monthly Spousal Maintenance
$0
Per month estimate
Est. Annual Amount
$0
Per year estimate
Est. Duration
—
Based on Illinois norms
Est. Total Paid
$0
Over full duration
⚠️ Remember: This is an estimate only. Illinois judges consider many factors beyond income alone — including each spouse’s earning capacity, age, health, standard of living, and contributions to the marriage. Always consult a Illinois family law attorney.
Illinois Spousal Maintenance Facts
Official Term
Spousal Maintenance
Calculation Method
Statutory Formula
Typical Amount
33.3% of payor’s net minus 25% of recipient’s net
Duration Rule
Multiplier of marriage length (0.20x for 3 yrs to 1.0x for 20+ yrs)
Permanent Available?
Yes — available for long marriages
Fault Considered?
No — no-fault state
Key Law Note
Illinois has a statutory formula for both the amount and duration of spousal maintenance.
What to Know About Illinois Spousal Maintenance
- →Illinois uses a clear formula: 33.3% of payor’s net income minus 25% of recipient’s net income.
- →Illinois duration multipliers range from 0.20 for a 3-year marriage up to permanent for 20+ year marriages.
- →Illinois uses a statutory formula as a starting point — but judges can adjust based on the specific circumstances of your case.
Frequently Asked Questions
How is spousal maintenance calculated in Illinois?
Illinois uses a statutory formula to calculate spousal maintenance. The standard approach is: 33.3% of payor’s net minus 25% of recipient’s net. Courts may deviate from this formula based on specific circumstances.
How long does spousal maintenance last in Illinois?
Illinois spousal maintenance duration: Multiplier of marriage length (0.20x for 3 yrs to 1.0x for 20+ yrs). Permanent spousal maintenance is available in Illinois for long marriages where one spouse cannot become self-supporting.
Does fault affect spousal maintenance in Illinois?
Illinois is a no-fault state for spousal maintenance purposes. Marital misconduct such as adultery does not affect whether support is awarded or the amount.