How Long Does Maintenance Last in Illinois?
Last reviewed: March 2026
Illinois uses statutory formula to determine maintenance duration. Duration multiplier starts at 0.20 for <5yr marriage, increases by 0.04 per year bracket up to 0.80 for 19-20yr; 20+yr = indefinite (Source: 750 ILCS 5/504(b-1)(1.5))
How Illinois determines maintenance duration
Illinois is an equitable distribution state. Illinois refers to spousal support as “maintenance”. Illinois has a statutory formula that determines the maximum duration of maintenance based on the length of the marriage.
Source: 750 ILCS 5/504(b-1)(1.5)
Formula: 33.3% of higher income minus 25% of lower income. Capped so recipient gets no more than 40% of combined income.
Estimated maintenance duration by marriage length
The table below shows estimated maximum maintenance duration for different marriage lengths in Illinois.
| Marriage length | Est. max maintenance duration |
|---|---|
| 5 years | 1.2 years |
| 10 years | 4.4 years |
| 15 years | 9.6 years |
| 20 years | Indefinite (court discretion) |
| 25 years | Indefinite (court discretion) |
When does maintenance end in Illinois?
Maintenance in Illinois typically ends when:
- The court-ordered term expires
- The recipient spouse remarries
- Either party dies
- A court modifies or terminates the order due to a significant change in circumstances
In some cases, cohabitation with a new partner may also be grounds for modification or termination of maintenance in Illinois.
Is maintenance taxable in Illinois?
For divorce agreements finalized after December 31, 2018, maintenance is not deductible by the payer and not taxable to the recipient under federal tax law (Tax Cuts and Jobs Act). This applies in Illinois and all other states.
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