Spousal Support in Illinois: A Full Guide

Illinois calls alimony “maintenance.” Unlike states that give judges broad discretion over the amount and length of an award, Illinois uses a statutory guideline formula for most cases and a duration matrix tied to the length of the marriage. This guide explains who qualifies, how the formula works, how long payments last, and when they can be changed or ended under 750 ILCS 5/504.

Types of Maintenance in Illinois

Illinois recognizes several forms of maintenance, each with different rules for duration, modification, and enforcement:

• Temporary maintenance — Ordered while the case is pending under Section 501 to preserve the status quo. Temporary awards are discretionary and are not bound by the guideline formula. They end when the final judgment is entered.
• Fixed-term maintenance — A post-judgment award for a set number of months or years. Once the term expires, the obligation is permanently barred. Courts sometimes call this “rehabilitative” maintenance when the goal is helping the recipient become self-supporting.
• Reviewable maintenance — A fixed initial period with a stated review date. At the review hearing, the court re-evaluates need and ability to pay under the Section 510(a-5) factors and can extend, reduce, or terminate the award.
• Indefinite maintenance — No fixed end date. The award continues unless modified or terminated under Section 510. Courts most commonly use indefinite maintenance for marriages lasting 20 or more years.
• Maintenance in gross — A specific, nonmodifiable total dollar amount paid in installments, often used in place of a property distribution. Because it is a fixed sum, it cannot be modified after entry.

When Is Maintenance Awarded

A court first decides whether maintenance is appropriate by weighing the non-exclusive factors in Section 504(a). Unlike Texas or other fault-based states, Illinois courts decide maintenance without regard to marital misconduct. The most commonly invoked factors include:

• Income, property, and needs of each party
• Present and future earning capacity, including any impairment from domestic duties or delayed education
• Time necessary for the recipient to acquire education, training, or employment
• Standard of living established during the marriage
• Duration of the marriage
• Age and physical and emotional condition of both parties
• Contributions by the requesting spouse to the other's education, training, or career
• Tax consequences of the property division and maintenance award
• Any valid agreement between the parties

The factors overlap significantly with those courts consider when dividing marital property. Understanding how maintenance interacts with Illinois marital property division is important because property each spouse receives can reduce or eliminate the need for ongoing support.

The Guideline Formula

When the parties' combined gross annual income is below $500,000 and the payor has no prior child support or maintenance obligations, Illinois courts apply statutory guidelines under Section 504(b-1). The formula uses net income as defined by the child support statute (Section 505):

Guideline amount: 33.33% of the payor's net income minus 25% of the payee's net income. The result cannot cause the payee's total net income (their own net income plus maintenance) to exceed 40% of the parties' combined net income.

For example, if the payor earns $10,000 per month net and the payee earns $3,000 per month net, the raw formula produces $2,583 per month. But the 40% combined-income cap ($5,200) limits the payee's total to $5,200, reducing the award to $2,200 per month.

When combined gross income reaches $500,000 or the payor already has support obligations from a prior case, the guidelines do not apply. The court makes a non-guideline award after analyzing all Section 504(a) factors and must state what the guideline result would have been and why it deviated.

See how Illinois maintenance might apply to your situation:

How Long Does Maintenance Last

Duration is calculated by multiplying the length of the marriage (measured from the wedding to the date the petition was filed) by a factor that increases with marriage length:

• Under 5 years: multiply by .20
• 5 to under 6 years: multiply by .24
• 6 to under 7 years: multiply by .28
• 7 to under 8 years: multiply by .32
• 8 to under 9 years: multiply by .36
• 9 to under 10 years: multiply by .40
• 10 to under 11 years: multiply by .44
• 11 to under 12 years: multiply by .48
• 12 to under 13 years: multiply by .52
• 13 to under 14 years: multiply by .56
• 14 to under 15 years: multiply by .60
• 15 to under 16 years: multiply by .64
• 16 to under 17 years: multiply by .68
• 17 to under 18 years: multiply by .72
• 18 to under 19 years: multiply by .76
• 19 to under 20 years: multiply by .80
• 20 or more years: Court may order maintenance for a term equal to the marriage length or indefinitely

A 12-year marriage, for example, produces a duration of .52 × 12 = 6.24 years, or roughly 75 months. Courts may credit time already spent paying temporary maintenance against the guideline duration.

Interaction with Child Support

When both maintenance and child support are at issue, Illinois courts typically fix maintenance first, then calculate child support using the Income Shares model. Court-ordered maintenance paid in the same case is deducted from the payor's income and added to the recipient's income for child support purposes.

A safety valve applies: if guideline maintenance plus guideline child support would exceed 50% of the payor's net income, the court may deviate from one or both sets of guidelines. This prevents combined support obligations from consuming so much of the payor's income that they cannot cover their own basic expenses.

Modification and Termination

Either party can petition to modify or terminate a maintenance order by demonstrating a substantial change in circumstances. Section 510(a-5) lists factors courts must consider, including changes in income, employment, health, property acquired after the judgment, and whether the recipient has made reasonable efforts toward self-support.

Retirement is a common basis for modification petitions but is not an automatic ground for reduction or termination. Courts examine the retiree's age, health, motivation and timing, ability to pay after retirement, and the recipient's ability to provide for themselves.

Unless the parties agree otherwise in a written agreement approved by the court, maintenance terminates automatically upon:

• Death of either party
• Remarriage of the recipient — The recipient must give at least 30 days' advance notice of intent to remarry (or within 72 hours if the decision occurred within 30 days). The payor is entitled to reimbursement for any maintenance paid after the remarriage date.
• Cohabitation — If the recipient cohabits with another person on a resident, continuing, conjugal basis, the obligation terminates by operation of law as of the date cohabitation began. Courts apply a totality-of-the-circumstances test that looks at the length and nature of the relationship, time spent together, interrelation of personal and financial affairs, and other hallmarks of a marriage-like partnership. A purely platonic or economic living arrangement does not qualify.

Parties can also agree to make maintenance nonmodifiable in amount, duration, or both. If such a clause is included in the marital settlement agreement, the court generally cannot later change the terms, even if circumstances shift significantly. When weighing your options, see our guide on Illinois uncontested vs. contested divorce.

Tax Treatment

For divorce instruments executed after December 31, 2018, maintenance is not deductible by the payer and not taxable to the recipient under the federal Tax Cuts and Jobs Act. Orders entered before January 1, 2019 keep the old deductible/taxable treatment unless a later modification expressly elects TCJA rules. IRS Publication 504 covers these rules in detail.

Illinois imposes a flat 4.95% state income tax, but the state follows federal treatment for maintenance—no separate state-level deduction exists for post-2018 orders. Both parties should account for this when projecting post-divorce cash flow.

Frequently Asked Questions

Does adultery or marital misconduct affect maintenance in Illinois? No. Section 504(a) directs courts to decide maintenance “without regard to marital misconduct.” Neither infidelity nor other fault-based grounds create or block eligibility.

What if our combined income exceeds $500,000? The statutory formula does not bind the court. Instead, the judge sets a non-guideline award after weighing all Section 504(a) factors and must explain the deviation. Courts often use the duration matrix as a persuasive reference point even in high-income cases.

Can the court impute income if my spouse is voluntarily unemployed? Yes. Courts can impute income based on qualifications, work history, and the job market when a party is voluntarily unemployed or underemployed. The analysis is fact-specific and must consider health, abilities, and market conditions.

Will moving in with a roommate terminate my maintenance? Not automatically. The statutory test requires cohabitation on a “resident, continuing, conjugal basis”—a marriage-like partnership. A purely economic or platonic living arrangement does not trigger termination.