Alimony, also called spousal support or maintenance, is one of the most unpredictable parts of a divorce. In some states the calculation is essentially arithmetic. In others, two judges in the same county can produce wildly different orders on identical facts. Knowing which kind of state you are in changes how you should approach the case, what to ask your attorney, and what offers to take seriously in negotiation.
This guide breaks down the three formula types, walks through the math in each formula state, lists the discretionary factors used everywhere else, and explains how to come up with a realistic estimate before you spend money on a consultation. For a state-specific estimate, use our Alimony Calculator.
The three approaches states use
Alimony statutes fall into three categories.
Formula states apply a guideline calculation, often based on a percentage of income or a function of the income difference between spouses. Judges can deviate from the guideline, but only with a written explanation. These states produce the most predictable outcomes. Examples include Colorado, Illinois, Massachusetts, New Hampshire, and New York (for cases under the income cap).
Discretionary states give the judge full authority to decide whether alimony is owed, how much, and for how long. The statute lists factors the judge must consider, but does not constrain the result with a formula. Most states fall in this group, including Texas, Florida, California, Pennsylvania, Georgia, North Carolina, and most of the South and West.
Hybrid states use a guideline or rule of thumb for some types of alimony (typically temporary support during the case) but leave permanent post-divorce alimony to the judge's discretion. California and New Jersey are good examples: the temporary support guideline is well known and rarely deviated from, but final orders are case-by-case.
The practical effect is significant. In a formula state, your attorney can usually quote you a reasonably narrow range for both the amount and duration after a fifteen-minute conversation. In a discretionary state, the same attorney may give you a range four to six times wider.
Formula states: how the math actually works
These five examples cover the most-used alimony formulas in the country.
Colorado
Colorado uses a formula for marriages of three years or more, capped at combined incomes of $240,000 per year (above the cap, judges have full discretion).
Amount: 40% of higher earner's monthly gross income, minus 50% of lower earner's monthly gross income, with the requirement that the lower earner not end up with more than 40% of combined gross income.
Duration: A sliding scale starting at 31% of marriage length for a 3-year marriage and rising to 50% for a 20-year marriage. Marriages over 20 years can produce indefinite alimony at the judge's discretion.
Example: Higher earner makes $10,000/month, lower earner makes $4,000/month. 40% of $10,000 = $4,000. 50% of $4,000 = $2,000. Initial result: $2,000/month. Cross-check: combined income is $14,000; recipient's 40% cap is $5,600. Recipient already has $4,000 from earnings, leaving $1,600 of capacity for alimony. The order is reduced to $1,600/month. After a 10-year marriage, alimony lasts 4.5 years.
Illinois
Illinois uses a formula for combined gross incomes under $500,000 per year.
Amount: 33.3% of payer's net income, minus 25% of payee's net income. The result cannot make the payee's total income exceed 40% of the parties' combined net income.
Duration: A sliding scale from 20% of marriage length (under 5 years) to 100% (20+ years).
Example: Payer's net income $7,000/month, payee's $3,500/month. 33.3% of $7,000 = $2,331. 25% of $3,500 = $875. Initial result: $1,456/month. Cross-check: combined net is $10,500; payee's 40% cap is $4,200. Payee already nets $3,500, leaving $700 of capacity. Order is reduced to $700/month.
Massachusetts
Massachusetts uses a guideline of 30% to 35% of the difference between the spouses' gross incomes. The result cannot exceed the recipient's actual need.
Duration: A scale tied to marriage length: up to 50% of months married for marriages 5 years or less, rising to indefinite for marriages over 20 years.
Example: Higher earner $9,000/month, lower earner $3,000/month. Difference: $6,000. 32.5% (midpoint): $1,950/month. After a 12-year marriage, support lasts up to 80% of months married, or about 9.6 years.
New Hampshire
New Hampshire's formula caps alimony at 23% of the difference between the parties' gross incomes (with allowable offsets for taxes, health insurance, and child support).
Duration: Generally 50% of marriage length, with extensions possible in long marriages.
New York
New York uses a two-part formula based on payer income up to a $228,000 cap (the cap is updated periodically).
Without children (no child support): 30% of payer's income minus 20% of payee's income, OR 40% of combined income minus payee's income, whichever is less.
With child support: 20% of payer's income minus 25% of payee's income, OR the same combined-income cap.
Above the income cap, judges may use the formula or apply discretion.
Example (no children): Payer $9,000/month, payee $3,000/month. Calculation A: 30% of $9,000 = $2,700, minus 20% of $3,000 = $600. Result: $2,100. Calculation B: 40% of $12,000 = $4,800, minus payee's $3,000 = $1,800. Lower of the two: $1,800/month.
Discretionary states: the factors that actually matter
In a state without a formula, the judge weighs statutory factors. The list varies but almost always includes:
- Length of the marriage. The single most important factor. Short marriages (under 7 years) rarely produce long-term alimony. Long marriages (over 15 years) often do.
- Standard of living during the marriage. Used as a benchmark for what the supported spouse should be able to maintain, at least in the short term.
- Each spouse's earning capacity. Not just current income but what each spouse could reasonably earn given education, work history, and the local job market.
- Contributions to the marriage. Career sacrifices, support of the other spouse's education or career, child-rearing, homemaking.
- Age and health. Older or less healthy spouses are more likely to receive longer support.
- Financial resources. Assets received in the property division, separate property, expected inheritances.
- Tax consequences. Particularly relevant after the 2018 tax law change.
- Fault. A minority of states (including Georgia, North Carolina, and Virginia) consider marital misconduct. Most states do not.
The factors get applied through case law and local norms, which is why local family law attorneys are so much more accurate than out-of-state lawyers when estimating discretionary cases.
How long alimony lasts
Duration follows three rough patterns regardless of state:
- Short marriages (under 5 years): Usually no alimony, or short rehabilitative support of 1 to 2 years.
- Mid-length marriages (5 to 15 years): Alimony lasting 25% to 50% of the marriage is common. Most states discourage indefinite support in this range.
- Long marriages (15+ years): Alimony often lasts 50% of marriage length or longer. Marriages over 20 years can produce indefinite ("permanent") alimony, though "permanent" almost always ends at retirement age, remarriage, or death.
Many states have explicit duration caps tied to marriage length. Florida and Massachusetts both eliminated permanent alimony in recent reforms; both now cap duration based on marriage length.
Types of alimony
Most states recognize several types, and the type affects both amount and duration:
- Temporary (pendente lite) alimony. Paid during the divorce case, before the final order. Often calculated using a guideline even in discretionary states.
- Rehabilitative alimony. Time-limited support to allow the recipient to retrain or finish a degree. Common in mid-length marriages.
- Permanent or long-term alimony. Available after long marriages. Increasingly restricted in modern statutes.
- Reimbursement alimony. A payment to compensate one spouse for funding the other's education or training during the marriage. Used in places like Massachusetts and New Jersey.
- Lump-sum alimony. A one-time payment in lieu of ongoing support. Often used when one spouse wants a clean break.
If the case settles, the parties can structure alimony any way they want, including combining types.
How to estimate alimony before the first attorney meeting
You can produce a reasonably good estimate yourself with three pieces of information:
- Your state's category. Formula, discretionary, or hybrid.
- The income difference between spouses. Gross monthly income for each.
- The marriage length. Years from wedding to date of separation (or filing, depending on the state).
If you are in a formula state, run the math from the section above. If you are in a discretionary state, a useful starting point is 25% to 35% of the income difference, applied for 30% to 50% of the marriage length. That range will almost certainly bracket the actual order in a typical case.
Our Alimony Calculator handles all of this automatically and applies your state's specific rules.
When alimony ends
Alimony orders end on:
- A date specified in the order. Most modern alimony orders have explicit end dates.
- Remarriage of the recipient. Almost universal across states, though it is sometimes waivable.
- Cohabitation. Many states allow modification or termination if the recipient cohabits with a new partner. The standard varies (some require a "marriage-like" relationship; others apply a financial-dependence test).
- Death of either party. Orders end at death unless secured by life insurance.
- Court modification. A substantial change in circumstances (job loss, retirement, disability, significant income change) can support a modification motion.
Modification standards vary. Some states allow modification of any alimony order; others (notably for non-modifiable settlements) hold the parties to whatever they agreed to.
Tax treatment after 2018
The Tax Cuts and Jobs Act of 2017 changed alimony tax treatment for any divorce finalized after December 31, 2018:
- Payer: No longer deductible. You pay alimony out of after-tax income.
- Recipient: No longer counted as taxable income.
For divorces finalized before 2019, the old rules still apply unless the order is modified and the modification specifies the new rules.
This change increased the after-tax cost of paying alimony significantly. A payer in the 32% bracket who used to pay $3,000 per month at an after-tax cost of about $2,040 now pays the full $3,000. Many post-2018 cases negotiate lower amounts to reflect the lost deduction.
Run your numbers
Alimony is one of the most consequential pieces of a divorce settlement. A few hundred dollars per month over ten years is over $100,000 of value. Take the time to model multiple scenarios. Our Alimony Calculator will show you a state-specific estimate, and the Divorce Cost Estimator puts that alongside the rest of your costs.
This estimate is for planning purposes only and does not constitute legal or financial advice. Consult a licensed family law attorney in your state for guidance specific to your situation.