Updated September 1, 2026. Quick answer: When Illinois's statutory guideline applies, the amount starts with 33 1/3% of the payor's net annual income minus 25% of the payee's net annual income.
This page is limited to the controlling Illinois alimony rule captured below. It does not substitute a generic gray-divorce checklist for the state-specific answer.
The state rule that changes the answer
- When Illinois's statutory guideline applies, the amount starts with 33 1/3% of the payor's net annual income minus 25% of the payee's net annual income.
- The result is capped so the payee's net income plus maintenance does not exceed 40% of the parties' combined net income.
- For a marriage of 20 years or more, the court may set maintenance for the marriage length or for an indefinite term.
Build the later-life review sheet
Copy each factor, threshold, formula, or procedure named in the controlling section into a separate field before comparing possible support structures. Do not add an input the source does not name.
Label each entry as eligibility, amount, duration, termination, or required finding, as applicable. That keeps a threshold rule from being presented as a guaranteed result.
Keep adjacent divorce questions with their owners
This page does not restate property-division, QDRO or pension, Social Security or Medicare, estate, divorce-statistics, or debt content.
Primary source and verification
The controlling source used here is 750 Ill. Comp. Stat. 5/504. Confirm the current official text and the facts of the order before acting; this is a source-backed planning guide, not individualized legal advice.