Alimony is often one of the most stressful things to think about when going through a divorce. Knowing how long you might have to pay is important to planning your financial future. Known as spousal maintenance in Illinois, alimony is subject to a duration formula to help judges calculate how long it should last. Judges ultimately have discretion on whether spousal support is appropriate and how long it should last, but the law helps guide these decisions.
At Kulerski & Cornelison, our team serves families in DuPage and Cook counties. Let us help you with spousal support concerns, whether you may receive it or have to pay it in your Illinois divorce.
Illinois Alimony Duration Formula
If your marriage lasted less than 20 years, Illinois uses a formula to determine how long spousal maintenance should last. It multiple the years you were married by a percentage, as per the chart below:
| Length of Marriage | Duration of Your Alimony Payments |
| 0-5 Years | 20% of marriage length |
| 5-6 Years | 24% of marriage length |
| 6-7 Years | 28% of marriage length |
| 7-8 Years | 32% of marriage length |
| 8-9 Years | 36% of marriage length |
| 9-10 Years | 40% of marriage length |
| 10-11 Years | 44% of marriage length |
| 11-12 Years | 48% of the marriage length |
| 12-13 Years | 52% of the marriage length |
| 13-14 Years | 56% of the marriage length |
| 14-15 Years | 60% of the marriage length |
| 15-16 Years | 64% of the marriage length |
| 16-17 Years | 68% of the marriage length |
| 17-18 Years | 72% of the marriage length |
| 18-19 Years | 76% of the marriage length |
| 19-20 Years | 80% of the marriage length |
| 20+ | 100% of the marriage length or indefinite |
Can a Court Award Permanent Alimony in Illinois?
A court is permitted to award permanent alimony, or for periods longer than on the chart. For example, if a couple is married for 28 years, the court could grant alimony of 28 years, or could choose to make the spousal support indefinite.
Whether the court will do so depends on the individual facts of your case. It is best to talk to an attorney about your situation if you have been in a long-term marriage.
Types of Alimony in Illinois
The State of Illinois allows for several types of spousal maintenance. Each differs on how long it may last.
- Fixed-Term Maintenance
- Reviewable Maintenance
- Permanent Maintenance
- Temporary Maintenance
Can Spousal Maintenance End Early in Illinois?
Even if the court sets a specific period of time the alimony should last, it could end early if:
- The spousal support recipient gets remarried
- The receiving party begins to live with a romantic partner
- Either party dies
- There was a substantial change of circumstances that affects spousal maintenance
Can Alimony Be Modified?
Yes. Unless the maintenance order is non-modifiable by agreement, either party can request a modification if there’s a substantial change in circumstances. This includes changes in income, employment, health, or financial need.

Lump-Sum and Non-Guideline Maintenance
In some cases, spouses may agree to a lump-sum buyout of maintenance obligations. Courts may also deviate from the statutory formula if the guideline would be inappropriate or unfair. Factors include:
- Each party’s income and earning capacity
- Standard of living during the marriage
- Age and health of both spouses
- Contributions to the marriage
Learn More About Illinois Alimony and How Long It Might Last
How long you might pay alimony will depend a lot on how long you were married, and other circumstances of your joint lives. Your financial situation, ability to pay, and any negotiations may all be taken into account. Speak with your licensed Illinois spousal maintenance lawyer before making any decisions or assumptions about alimony.
At Kulerski & Cornelison, our family law attorneys are ready to help. Contact us today for a consultation of your case.
