Alimony Calculator

The Alimony Calculator (also called a spousal support calculator) helps you estimate monthly alimony payments based on both spouses' incomes, the length of the marriage, and other factors. It uses two widely referenced calculation methods — the AAML formula and the income-difference percentage method — to give you a range of estimates.

How Is Alimony Calculated?

Unlike child support, there is no single nationwide formula for calculating alimony in the United States. Each state has its own guidelines, and judges have significant discretion. However, two common approaches are frequently referenced:

AAML Formula (American Academy of Matrimonial Lawyers)

This formula calculates alimony as 30% of the payer's gross income minus 20% of the recipient's gross income. The result is then capped so the recipient's total income (their own income plus alimony) does not exceed 40% of the combined marital income.

One-Third Income Difference Method

This simpler approach sets alimony at approximately one-third (33.3%) of the difference between the two spouses' incomes. It provides a quick estimate that falls within the range used by many state guidelines.

Factors That Affect Alimony

Alimony Duration Guidelines

The length of alimony payments typically correlates with marriage duration:

• Short marriages (under 5 years): Support for approximately 30–40% of the marriage length
• Medium marriages (5-10 years): Support for approximately 40% of the marriage length
• Long marriages (10-20 years): Support for approximately 60–80% of the marriage length
• Very long marriages (20+ years): Potentially permanent or indefinite alimony in many states

Tax Treatment of Alimony

The tax treatment of alimony changed significantly with the Tax Cuts and Jobs Act (TCJA) of 2017:

• Agreements after Dec 31, 2018: Alimony is not tax-deductible for the payer and not taxable income for the recipient
• Agreements before Jan 1, 2019: Alimony is tax-deductible for the payer and is taxable income for the recipient (unless the agreement has been modified to adopt the new rules)

Types of Alimony

• Temporary Alimony: Paid during divorce proceedings before a final settlement
• Rehabilitative Alimony: Short-term support to help a spouse become self-sufficient through education or training
• Permanent Alimony: Ongoing support, typically for long marriages where one spouse cannot become self-supporting
• Lump-Sum Alimony: A one-time payment instead of ongoing monthly payments
• Reimbursement Alimony: Compensates a spouse who supported the other through education or career advancement

How to Use This Calculator

1. Enter incomes: Input each spouse's gross monthly income. The calculator will automatically identify the higher earner as the potential payer.
2. Enter marriage duration: Input the number of years the marriage lasted. This affects both the estimated payment amount and duration.
3. Select children status: Indicate whether there are minor children and which spouse has primary custody.
4. Select agreement date: Choose the tax treatment era — post-2018 (not deductible) or pre-2019 (deductible) — for accurate financial analysis.
5. Review results: Compare the two calculation methods, analyze the income impact, review the payment timeline, and read the personalized insights.

Frequently Asked Questions

How is alimony calculated in the US?

There is no single federal formula. Most states consider income disparity, marriage duration, standard of living, age and health of both spouses, and each spouse's earning capacity. Common formulas include the AAML method (30% of payer's income minus 20% of recipient's income) and the one-third income difference method.

Is alimony tax-deductible?

For agreements executed after December 31, 2018, alimony is NOT tax-deductible for the payer and NOT taxable income for the recipient. For pre-2019 agreements, the old rules (deductible/taxable) still apply unless modified.

How long does alimony last?

Duration depends primarily on marriage length. Short marriages typically receive support for about 30–40% of the marriage duration, while long marriages (20+ years) may qualify for permanent alimony in some states.

What is the difference between alimony and child support?

Alimony is paid from one spouse to another to maintain the lower-earning spouse's standard of living. Child support is specifically for children's expenses. They are calculated separately, and a spouse may receive both.

Can alimony be modified or terminated?

Yes. Alimony can typically be modified if there is a substantial change in circumstances such as job loss, significant income change, retirement, or disability. Alimony usually terminates upon remarriage, cohabitation (in many states), or death of either party.