FAMILY LAW CALCULATORS

Alimony Duration Calculator — United States

Estimate how long alimony lasts and the monthly amount using common state durational factors and the AAML income-difference formula.

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Longer marriages generally produce longer alimony durations.

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Disclaimer: Alimony law varies enormously by state; this uses a common national formula. Educational estimate only. Not legal advice.

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Frequently Asked Questions

How long does alimony last in the US?
Duration varies by state, but a common guideline ties it to marriage length: for marriages under 10 years, alimony often runs about half the marriage length; for 10–20 year marriages, roughly 60–70%; and for marriages of 20+ years, many states allow long-term or permanent alimony. Some states, like Texas, impose statutory caps (e.g., a maximum of 5, 7, or 10 years depending on marriage length).
How is the amount of alimony calculated?
There is no national formula. Many practitioners use the American Academy of Matrimonial Lawyers (AAML) guideline: 30% of the payor's gross income minus 20% of the recipient's gross income, with a cap so the recipient's total income does not exceed roughly 40% of the couple's combined income. States like Illinois and New York have their own statutory formulas.
What is the difference between temporary, rehabilitative, and permanent alimony?
Temporary (pendente lite) alimony is paid during the divorce process. Rehabilitative alimony supports a spouse for a set period while they gain education or job skills to become self-supporting. Permanent (or long-term) alimony continues indefinitely, usually after long marriages, ending on remarriage, death, or a material change in circumstances.
Is alimony tax deductible in the US?
No, not for divorces finalized after December 31, 2018. The Tax Cuts and Jobs Act eliminated the alimony deduction for the payor and made payments non-taxable to the recipient for agreements executed in 2019 or later. Older orders may still follow the pre-2019 tax treatment unless modified.

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