The landscape of Illinois and DuPage County divorce law was fundamentally reshaped by major amendments to the Illinois Marriage and Dissolution of Marriage Act (IMDMA) in 2018 and 2019. These changes transitioned the state to a standardized, mathematical schedule for determining both the amount and the duration of maintenance (alimony).
The most significant shift was the move to a Net Income calculation. Because maintenance is no longer tax-deductible for the payer or taxable for the recipient at the federal level, the law now calculates awards based on what each spouse actually takes home after taxes.
Below, we outline the current formulas used to estimate maintenance awards. For a personalized analysis of your case, please contact our Oakbrook Terrace or Chicago offices.
Maintenance Estimator
Illinois Statutory Maintenance Formula (Net Income Basis)
How Maintenance is Determined: Amount and Duration
A statutory maintenance award in Illinois is broken down into two components:
- The Amount: The monthly or annual payment figure.
- The Duration: The length of time those payments will continue.
1. Calculating the Duration
The duration of maintenance is determined by the length of the marriage at the time the divorce is filed. To find the duration, multiply the number of years of marriage by the corresponding factor:
- Less than 5 years: 0.20
- 5 years: 0.24
- 6 years: 0.28
- 7 years: 0.32
- 8 years: 0.36
- 9 years: 0.40
- 10 years: 0.44
- 11 years: 0.48
- 12 years: 0.52
- 13 years: 0.56
- 14 years: 0.60
- 15 years: 0.64
- 16 years: 0.68
- 17 years: 0.72
- 18 years: 0.76
- 19 years: 0.80
- 20 or more years: The court may order permanent maintenance or a duration equal to 100% of the length of the marriage.
2. Calculating the Amount
For most couples with a combined gross income of less than $500,000, the statutory formula for the amount is:
(33.3% of the Payer’s Net Income) – (25% of the Receiver’s Net Income)
The 40% Rule (The Cap): The law stipulates that the recipient’s total net income (their own income plus the maintenance received) cannot exceed 40% of the combined household net income.
Examples of Maintenance Calculations
Two-Income Household
Consider a marriage of 15 years where both spouses earn an income:
- Spouse A (Payer): Annual Net Income of $120,000
- Spouse B (Receiver): Annual Net Income of $60,000
- Combined Net Income: $180,000
Calculating Amount:
- ($120,000 x 33.3%) = $39,960
- ($60,000 x 25%) = $15,000
- $39,960 – $15,000 = $24,960 (Raw Maintenance Amount)
Applying the 40% Cap:
- 40% of combined income ($180,000) = $72,000.
- Spouse B’s new income ($60,000 + $24,960) = $84,960.
- Since $84,960 exceeds the $72,000 cap, the award is reduced to $12,000 per year ($72,000 – $60,000).
Calculating Duration: 15 years of marriage x 0.64 factor = 9.6 Years.
Single-Income Household
Consider a marriage of 14 years where only one spouse earns an income:
- Spouse A (Payer): Annual Net Income of $100,000
- Spouse B (Receiver): No income
- Combined Net Income: $100,000
Calculating Amount:
- ($100,000 x 33.3%) = $33,300
- ($0 x 25%) = $0
- $33,300 – $0 = $33,300 (Raw Maintenance Amount)
Applying the 40% Cap:
- 40% of combined income ($100,000) = $40,000.
- Spouse B’s new income ($0 + $33,300) = $33,300.
- Because $33,300 is under the $40,000 cap, the full $33,300 per year is awarded.
Calculating Duration: 14 years of marriage x 0.60 factor = 8.4 Years.
Our maintenance calculator is intended only as an estimation tool and does not replace the advice of a qualified attorney.
Contact Our DuPage County Alimony Lawyers
The IMDMA and current Illinois maintenance laws were to standardize how support is determined. However, every divorce is unique. The court may deviate from these guidelines based on specific factors like the standard of living during the marriage, the age and health of the parties, or parental responsibilities.
If you have questions about your divorce or maintenance rights, contact Dolci Weiland & Sendlak at (630) 261-9098. We offer free initial consultations to review your case and explore your options.