Quick answer: How is alimony calculated? It depends on the state. A few states set a statutory formula or advisory guideline for the amount, such as Illinois, New York and Colorado, and some cap the amount or the duration, such as Texas and Florida. Most others have the judge weigh factors like the length of the marriage, each spouse's income and need, and set both amount and term.
On this page:
- Two ways states set alimony
- States with a formula or guideline
- Caps and limits on amount and duration
- When the judge decides: the factors
- How long alimony lasts
- How alimony fits with property and child support
- How to estimate your alimony
Two ways states set alimony
Alimony is financial support from one spouse to the other after a marriage ends. The Legal Information Institute notes that, depending on the state, it can rest on factors such as the age of the parties, the length of the marriage and their incomes. States then take one of two paths. Some write a formula or guideline into law so the amount can be computed. Others list factors and leave the amount and the term to the judge. Because the law differs so much, the Alimony Calculator works state by state: it applies the formula where there is one and shows the statute and factors where there is not.
States with a formula or guideline
These four show how different a formula can look.
| State | What the law sets | Binding? |
|---|---|---|
| Illinois | Guideline maintenance of 33 1/3% of the payor’s net income minus 25% of the payee’s, capped so the payee does not exceed 40% of combined net income; applies below a combined income ceiling | Guideline; the court may depart after weighing statutory factors (750 ILCS 5/504) |
| New York | The lower of two amounts: 20% of the payor’s income minus 25% of the payee’s when child support is paid for children of the marriage and the payor is the non-custodial parent (otherwise 30% minus 20%), and 40% of combined income minus the payee’s income, up to an income cap | Formula, adjustable on listed factors (DRL 236(B)(6)) |
| Colorado | Advisory amount of 40% of combined monthly income minus the lower earner’s income, with an advisory term, for marriages of three years or more up to an income ceiling | Advisory only; no presumptive amount or term (C.R.S. 14-10-114) |
| Texas | No formula, but a cap: the lesser of $5,000 a month or 20% of the obligor’s average monthly gross income, and only if eligibility grounds are met | Binding cap (Tex. Fam. Code ch. 8) |
A formula is a starting point, not a promise. Courts in these states can still adjust for the facts, and the figure also depends on what counts as income and how each state treats taxes, which is why it helps to read whether alimony is taxable before comparing numbers.
Caps and limits on amount and duration
Even where there is no formula, a state may limit what a court can order. Texas allows maintenance only if the spouse seeking it will lack enough property to meet minimum reasonable needs and one of its eligibility grounds applies, such as a disability or a marriage of ten years or more where the spouse cannot earn enough. Florida limits durational alimony: it may not follow a marriage lasting under three years, and it may not exceed 50 percent of the length of a short-term marriage, 60 percent of a moderate-term marriage or 75 percent of a long-term marriage (Fla. Stat. 61.08). These limits can matter more than any formula, so check them for your state on its calculator page.
When the judge decides: the factors
In states without a formula the law lists factors, and the judge weighs them. The Institute’s list is typical: the parties’ ages, the length of the marriage, degrees earned, and their net monthly incomes and expenses. Colorado, for example, awards maintenance only if the spouse seeking it lacks sufficient property and cannot support himself or herself or is the custodian of a child. Because nothing converts the factors into a number, no calculator can predict a discretionary award, and honest tools show the factors and limits instead of a figure. Plan around ranges and talk to a local attorney about how your court tends to rule.
How long alimony lasts
The Institute notes that the duration of alimony is often based on the length of the marriage: the longer the marriage, the longer the payments. Several states turn that idea into a table. Illinois multiplies the length of the marriage by a factor from .20 for marriages under five years up to .80 for 19 to under 20 years, and for marriages of 20 years or more the court may order maintenance for a period equal to the length of the marriage or for an indefinite term. Texas caps maintenance at 5, 7 or 10 years depending on the length of the marriage, unless a disability or the care of a young child prevents earning enough. Some awards also end automatically, for example on the death of either party.
How alimony fits with property and child support
Alimony is rarely decided alone. Illinois treats each party’s property as the first factor in setting maintenance, and if guideline maintenance and child support together exceed 50% of the payor’s net income the court may set non-guideline amounts for either. New York calculates maintenance before child support and treats an award of maintenance as a factor in the equitable distribution of property. In practice, spouses often trade one against the other, so look at how your state divides property and how child support is calculated together with alimony.
How to estimate your alimony
Start with your state in the Alimony Calculator, then run the Property Division Calculator and the Child Support Calculator so the three numbers fit together. If an order is already in place and your situation changes, see whether you can modify alimony. The family law calculators cover every state, and our methodology page explains how each figure is verified. For advice on your own case, talk to a licensed family law attorney in your state.