In Illinois, "maintenance," formerly known as "alimony," is the financial support one spouse may be ordered to pay the other spouse following a divorce or legal separation. Maintenance is awarded to a financially disadvantaged spouse, or the spouse that makes less money, to try to assure that spouse can meet their reasonable living expenses, with the goal of eventually becoming financially independent. Factors considered by a court in deciding whether maintenance is needed are:

•       The income and property of each spouse;
•      The standard of living established during the marriage;
•      The duration of the marriage; the physical and emotional condition of each party; and
•      The time necessary for the recipient spouse to acquire education or training to find better employment.

In Illinois in 2025, guidelines were established for determining maintenance, the amount of maintenance, and the duration of maintenance. Maintenance is calculated based on the combined gross annual incomes of the parties earning less than $500,000.00 per year and the calculation is 33.33% of the net annual income of the payor spouse minus 25% of the payee spouse's net annual income. However, the resulting maintenance amount when added to the payee's net annual income, cannot exceed 40% of the combined net income of both parties.

For marriages of 20 years or more, the court has discretion to order maintenance for a period equal to the length of the marriage or for an indefinite term.

If the combined gross annual income of the parties is in excess of $500,000.00, the court may consider the statutory guideline, but the court will try to assure the needs of the payee are met without unduly burdening the payor.

Courts may deviate from the statutory guidelines if the court believes the application of the guidelines are inappropriate, but the court must state, in writing, specific findings to justify such deviations.