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Category: Family Law Finances

How is Alimony Calculated in Illinois?

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Written by Olivia St. Clair Long, JD on 6.21.22

Virtually every aspect of getting a divorce is stressful. And while you’re trying to move out of a home you probably bought together and figure out a practical custody arrangement, the issue of money will likely be a constant worry.

After all, how do people afford to live separately, especially if one spouse earns significantly more or has been the historical ‘breadwinner’?

Alimony in Illinois

In Illinois, spousal maintenance or alimony is available to help lesser-earning spouses (male or female) transition out of a marriage. Alimony is money paid from one spouse to the other as financial support during and/or after a divorce to allow the lesser-earning spouse time to get back on their feet, continue their education, and otherwise get on with life without unnecessary financial strain.

Unlike child support, alimony is not mandatory in Illinois. Determining if alimony is appropriate and calculating how much a spouse is entitled to could potentially represent one of the most contentious issues in your divorce.

Illinois Spousal Maintenance Calculator

Illinois uses a formula outlined in the Illinois Marriage and Dissolution of Marriage Act to calculate spousal maintenance. However, keep in mind there are various factors to consider in divorce, and spousal support can be significantly influenced by the division of marital property, debts, and other obligations.

To accurately estimate what you can expect to pay or receive in spousal support, it’s best to consult an experienced family lawyer.

Generally, monthly spousal support in Illinois is calculated in one of three ways:

  1. The court takes 33% of the payor’s net monthly income minus 25% of the payee’s net income to equal the alimony paid each month (the payor’s income and maintenance cannot exceed 40% of the total incomes).
  2. The amount of alimony is zero because it’s determined, either by the court or as part of a divorce agreement, that spousal maintenance is not warranted.
  3. An appropriate amount of alimony is calculated outside of the standard formula based on the unique circumstances of the divorcing spouses.


Divorcing spouses can also choose their alimony payments independent of the court. A judge must approve the agreement, but it’s typically honored if both spouses agree and the alimony is equitable.

Factors That Impact Alimony in Illinois

When spousal maintenance is left up to the court in Illinois, specific criteria must be met before determining the amount, type, and duration. Section 750 ILCS 5/504(a) of the Illinois Marriage and Dissolution of Marriage Act considers:

  • Each party’s needs
  • The duration of the marriage
  • Each party’s income, assets, and debts
  • The standard of living established during the marriage
  • The receiving party’s current and future earning capacity
  • Any constraints on the receiving party’s earning capacity due to delayed education, training, or employment because of the marriage and domestic duties.
  • Any constraints on the paying party’s earning capacity
  • The time necessary for the receiving party to get education, training, and employment
  • The effect of any child custody and placement arrangements on a party’s ability to maintain employment
  • Each party’s age, health, station, occupation, amount and sources of income, vocational skills, employability, estate, and liabilities
  • The receiving party’s contributions to the paying party during their education, training, career, or license
  • All sources of public and private income, such as disability and retirement income
  • The tax consequences to each party
  • Any valid agreement of the parties
  • Any other factors that the court expressly finds to be just and equitable

You can probably tell that a lot of nuances exist when calculating alimony. For example, courts in Illinois may break the standard guidelines when considerable assets are involved (combined income of $500,000 or more, if there’s a significant income disparity between the spouses, or when one spouse already pays child support or alimony from a prior relationship.

Types of Spousal Support in Illinois

Because spousal maintenance intends to help lesser-earning spouses transition out of a marriage, Illinois accepts four main types of alimony arraignments based on the needs and circumstances involved.

  • Temporary Support helps a lesser-earning spouse while a divorce is in progress. Temporary maintenance can be replaced with a formal alimony plan as part of the final divorce decree.
  • Rehabilitative maintenance assists the payee in securing their own earning power after a divorce. Rehabilitative support is paid to the lesser-earning spouse while going to school or job training. Once the recipient enters (or reenters) the workforce, the payer may ask the court to reduce or stop payment.
  • Reviewable maintenance is another temporary form of support. Adjusting the amount and duration depends on the spouse’s ability to achieve financial independence.
  • Permanent maintenance is based on the length of the marriage and for spouses who are unlikely to become financially self-sufficient. Permanent alimony ends when either spouse dies or if the recipient remarries.

How Long Does Alimony Last in Illinois?

Again, various outside factors will influence spousal support determinations and agreements made between the parties involved regarding alimony. However, the duration of alimony payments in Illinois is typically tied to the length of time two people are married. For example, under the current 2018 Illinois maintenance guidelines, if your marriage lasted less than five years, you will generally receive alimony payments for 20% of that time (1 year).

To get an idea of how long alimony may last in your case, the table below lays out the approximate duration based on the length of a marriage. These figures are meant to guide and are still subject to change and a judge’s final determination.

0-5 years — 20%                          13 years — 56%
5 years — 24%                              14 years — 60%
6 years – 28%                                15 years — 64%
7 years – 32%                                16 years — 68%
8 years – 36%                                17 years — 72%
9 years – 40%                                18 years — 76%
10 years – 44%                               19 years — 80%
11 years – 52%                                 20 or more years — 100% or Indefinitely

Work with a Lawyer to Ensure Your Alimony Is Correct

While Illinois divorce law sets guidelines regarding alimony, a lot goes into a spousal support agreement, and no two cases are the same. An online alimony calculator is an ok place to start, but you won’t get the whole picture. A lot will depend on your unique situation, your soon-to-be ex, and your willingness to negotiate on important considerations.

If you’re facing divorce and want to discuss what amount of alimony you can realistically expect, it’s always best to consult an experienced divorce lawyer. In Evanston, IL, and the Northshore area, contact O. Long Law or call 847-556-8846.

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