How long does alimony last in Illinois?

Duration depends on marriage length. Under 5 years: 20% of marriage length. 5-6 years: 24%. 6-7 years: 28%. And so on, up to marriages of 20+ years where courts may award permanent maintenance or maintenance for the length of the marriage.

Can a working spouse get maintenance in Illinois?

Yes. Maintenance is based on income disparity, not unemployment. If your spouse significantly out-earns you, you may qualify for maintenance even with your own income. The formula accounts for both incomes.

Can maintenance be modified after divorce?

Yes, unless the divorce agreement explicitly states maintenance is non-modifiable. Either party can petition for modification based on substantial change in circumstances—job loss, retirement, significant income change, or recipient's cohabitation.

Does maintenance end if my ex remarries?

Yes. Under Illinois law, maintenance automatically terminates upon the recipient's remarriage. Cohabitation (living with a romantic partner on a continuing, conjugal basis) may also be grounds for termination or modification.

Illinois Maintenance (Alimony)

Q: How is maintenance calculated in Illinois?

For combined gross income under $500,000, Illinois uses a formula: 33.33% of the payor's gross income minus 25% of the recipient's gross income. The result cannot exceed 40% of combined gross income. Duration is based on length of marriage.

How spousal support is calculated, how long it lasts, and when it can be modified. The complete guide to Illinois maintenance law.

Key Point: In Illinois, alimony is called "maintenance." For divorces with combined gross income under $500,000, courts use a statutory formula. The formula determines both the amount AND duration of payments.

The Illinois Maintenance Formula

Under 750 ILCS 5/504, when combined gross income is under $500,000:

AMOUNT

(33.33% × Payor's Gross) - (25% × Recipient's Gross)

Result cannot exceed 40% of combined gross income

Example Calculation

Scenario: Husband earns $180,000/year, Wife earns $60,000/year, married 12 years

Combined Gross Income	$240,000/year
33.33% of Husband's Income	$60,000
25% of Wife's Income	$15,000
Calculated Maintenance	$45,000/year ($3,750/mo)
40% Cap Check	$96,000 (passes)

Duration (12-year marriage): 12 × 0.40 = 4.8 years of maintenance

Duration Guidelines

The length of maintenance depends on how long you were married:

Marriage Length	Duration Multiplier	Example
0-5 years	20% (0.20)	4 years → 0.8 years
5-6 years	24% (0.24)	5.5 years → 1.3 years
6-7 years	28% (0.28)	6.5 years → 1.8 years
7-8 years	32% (0.32)	7.5 years → 2.4 years
8-9 years	36% (0.36)	8.5 years → 3.1 years
9-10 years	40% (0.40)	9.5 years → 3.8 years
10-11 years	44% (0.44)	10.5 years → 4.6 years
11-12 years	48% (0.48)	11.5 years → 5.5 years
12-13 years	52% (0.52)	12.5 years → 6.5 years
13-14 years	56% (0.56)	13.5 years → 7.6 years
14-15 years	60% (0.60)	14.5 years → 8.7 years
15-16 years	68% (0.68)	15.5 years → 10.5 years
16-17 years	76% (0.76)	16.5 years → 12.5 years
17-18 years	84% (0.84)	17.5 years → 14.7 years
18-19 years	92% (0.92)	18.5 years → 17 years
19-20 years	100% (1.00)	19.5 years → 19.5 years
20+ years	Court discretion	Permanent or = marriage length

20+ Year Marriages: Courts have discretion to award permanent (indefinite) maintenance OR maintenance for the length of the marriage. This is where negotiation and litigation strategy matter most.

When the Formula Doesn't Apply

The statutory formula is a starting point, not a guarantee. Courts can deviate in several situations:

High-Income Cases ($500K+ Combined)

When combined gross income exceeds $500,000, courts have complete discretion. They consider:

• Standard of living during the marriage
• Each party's needs and resources
• Present and future earning capacity
• Career sacrifices made during marriage
• Age, health, and employability
• Tax consequences to each party

Factors That Can Increase Maintenance

Stay-at-Home Parent

Sacrificed career advancement for family. May need longer duration to rebuild earning capacity.

Supported Spouse's Career

Put spouse through professional school or relocated for their career opportunities.

Health Issues

Physical or mental health conditions limiting employment potential.

Older Spouse

Limited time to rebuild career or retirement savings. Courts consider age and employability.

Factors That Can Reduce/Eliminate Maintenance

Short Marriage

Marriages under 5 years rarely result in significant maintenance awards.

Similar Incomes

When both spouses earn comparable amounts, maintenance may not be warranted.

Substantial Property Award

Receiving significant assets in property division may reduce need for maintenance.

Voluntary Unemployment

Refusing to work when capable may result in imputed income, reducing the award.

Temporary vs. Permanent Maintenance

Temporary (Pendente Lite)

Awarded during the divorce process to maintain status quo.

• Requested via motion early in case
• Based on immediate financial need
• Ends when final judgment entered
• Often different amount than final award

Permanent (Post-Decree)

Awarded as part of final divorce judgment.

• Uses statutory formula or court discretion
• Duration based on marriage length
• Modifiable unless agreement says otherwise
• Terminates on remarriage or death

Modification & Termination

When Maintenance Can Be Modified

Unless your agreement explicitly states maintenance is non-modifiable, either party can petition for modification based on:

• Job loss or significant income reduction
• Retirement (planned, not strategic)
• Recipient's increased income
• Health changes affecting earning capacity
• Recipient's cohabitation with new partner

Automatic Termination Events

Remarriage

Recipient remarries

Death

Either party dies

Cohabitation*

Conjugal relationship

Cohabitation Warning: Under 750 ILCS 5/510(c), maintenance terminates if the recipient lives with another person "on a resident, continuing conjugal basis." This requires more than casual dating—courts look at shared finances, exclusivity, and relationship duration.

Tax Implications (Post-2018)

Important Change: For divorces finalized after December 31, 2018, maintenance is NOT tax-deductible for the payor and NOT taxable income for the recipient. This changed under the Tax Cuts and Jobs Act.

This means:

• Payors: You cannot deduct maintenance payments on your federal taxes
• Recipients: You don't report maintenance as income
• Planning impact: The "true cost" of maintenance to payors increased significantly
• Pre-2019 divorces: Old rules still apply unless you modify the agreement

Frequently Asked Questions

How is maintenance calculated in Illinois? +

For combined gross income under $500,000: (33.33% of payor's gross) minus (25% of recipient's gross), capped at 40% of combined income. Duration is based on marriage length using statutory multipliers. Above $500,000, courts have discretion.

How long does maintenance last? +

Duration depends on marriage length using multipliers: 5 years = 20%, 10 years = 40%, 15 years = 68%, etc. For marriages 20+ years, courts may award permanent maintenance or maintenance equal to the marriage length.

Can a working spouse get maintenance? +

Yes. The formula subtracts 25% of the recipient's income from 33.33% of the payor's income. So even with income, you may qualify if there's significant disparity. Maintenance is about equalizing the standard of living, not supporting the unemployed.

Is maintenance tax-deductible? +

For divorces after December 31, 2018: No. Maintenance is not deductible for the payor and not taxable for the recipient. Divorces finalized before 2019 follow the old rules unless modified.

Can maintenance be modified? +

Yes, unless the agreement explicitly says it's non-modifiable. Either party can petition based on substantial change: job loss, retirement, significant income changes, or recipient's cohabitation with a new partner.

Does maintenance end if my ex moves in with someone? +

Potentially. Illinois law allows termination if the recipient cohabits "on a resident, continuing conjugal basis." This requires proving a committed romantic relationship with shared living—not just roommates or casual dating.

Questions About Maintenance?

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This article is for informational purposes only and does not constitute legal advice. No attorney-client relationship is created by reading this content.