How Alimony Is Calculated in 2026
Alimony, also called spousal support or spousal maintenance, is a payment from one spouse to the other after a separation or divorce. Unlike child support, which follows a published state formula in all 50 states, alimony is discretionary in most of the country. Judges apply a list of statutory factors and reach a number that fits the facts of the marriage.
Because discretion produces wide variation, attorneys and mediators rely on guideline formulas as a starting point. This calculator gives you those starting points so you can see the realistic range before you negotiate or go to court.
The Formulas Courts and Attorneys Use
The AAML guideline takes 30 percent of the paying spouse's gross income and subtracts 20 percent of the receiving spouse's gross income. The result is capped so that the receiving spouse's total income does not exceed 40 percent of the couple's combined income. This is the most widely cited national guideline and the default in this calculator.
One third of the income difference is a common rule of thumb in states with no formula at all. If one spouse earns $7,000 per month and the other earns $3,000, the $4,000 gap produces roughly $1,333 per month in support.
The Massachusetts approach sets general term alimony at 30 to 35 percent of the difference in gross incomes, and the award may not exceed the receiving spouse's demonstrated need. Illinois uses a similar structure with 33.3 percent of the payor's net income minus 25 percent of the payee's net income, capped at 40 percent of combined net income.
The Texas cap is the strictest common rule. Spousal maintenance is limited to the lesser of 20 percent of the paying spouse's average gross monthly income or $5,000 per month, and eligibility itself is narrow.
How Long Alimony Lasts
Duration is usually a function of the length of the marriage. A widely used range is 0.3 to 0.5 years of support for every year of marriage. A 10 year marriage often produces 3 to 5 years of support. Marriages of 20 years or more are treated differently in many states, where support can run for half the length of the marriage or be awarded indefinitely until death, remarriage, or retirement.
Short marriages, generally under five years, frequently produce no alimony at all or only short rehabilitative support intended to let a spouse finish training or re-enter the workforce.
Alimony and Child Support Together
When both alimony and child support are in play, sequence matters. Most courts set spousal support first, then treat it as income to the recipient and a deduction for the payor when running the child support guideline. That means alimony can noticeably lower the child support number even though it raises the total amount transferred.
Enter your child support order in the calculator above to see the combined monthly outflow. If the combined figure leaves the paying spouse with less than about half of their gross income, courts typically reduce the alimony component rather than the child support component, because child support has priority.
To estimate the child support side of the equation, use the income shares calculator, the joint custody calculator, or your state guideline page.
Tax Treatment of Alimony
The Tax Cuts and Jobs Act changed the rules for any divorce or separation agreement executed after December 31, 2018. Alimony under those agreements is not deductible by the payor and is not reported as income by the recipient. Agreements finalized before 2019 generally keep the old treatment unless they were modified and the modification expressly adopts the new rules. This matters when comparing older settlement figures to current ones, because a pre-2019 payment of $2,000 per month was worth considerably less after tax to the payor.
Modifying or Ending Alimony
Most alimony orders can be modified when circumstances change substantially. Job loss, a serious medical condition, good faith retirement, or a significant raise for either spouse are the usual grounds. Alimony almost always terminates on the death of either spouse or the remarriage of the recipient, and many states also allow termination or suspension when the recipient cohabits with a new partner in a marriage like relationship.
Some settlement agreements make alimony non-modifiable in exchange for a lower amount or a shorter term. Read the language of any agreement carefully before signing, because a non-modifiable term survives even a total loss of income.
Using This Calculator
Pick the method that matches your state or your attorney's approach, enter both gross monthly incomes, set the length of the marriage, and add any child support already ordered. The result shows the guideline amount, the amount after a realistic affordability cap, the likely duration range, and the estimated total transfer over the life of the award.
Alimony outcomes vary widely by judge and jurisdiction. Use this estimate to prepare, then confirm the numbers with a licensed family law attorney in your state.