California Spousal Support Calculator
Temporary alimony while a divorce is pending, using the 40% / 50% guideline many California courts follow, plus what marriage length means for how long support lasts.
Temporary spousal support in California is commonly estimated as 40% of the higher earner's net income minus 50% of the lower earner's net income, after child support. There is no formula for long-term support. A judge weighs the factors in Family Code 4320.
Enter both spouses' net monthly income (after taxes, health insurance and mandatory retirement) and the length of the marriage up to separation.
Spousal Support Calculator
Estimated Temporary Spousal Support
Payer net after child support
Per year
How this is calculated
Temporary support (while the case is pending) is usually set with a guideline. Santa Clara County's Family Rule 3(C) states it as 40% of the payer's net income minus 50% of the recipient's net income, calculated on net income not allocated to child support. Many California courts use the same or a similar formula in their support software. Some counties use their own guideline, so check your local court rules.
If child support is also ordered, it is calculated first (see our child support calculator) and subtracted from the payer's net income before the 40% step.
Long-term (permanent) support after judgment has no formula. Courts are not supposed to use the temporary guideline for it. The judge weighs the factors in Family Code 4320, including each spouse's earning capacity, the marital standard of living, the length of the marriage, age and health, contributions to the other spouse's career, domestic violence history, and tax consequences.
How long support lasts. For a marriage under 10 years (measured from the wedding to the date of separation), a "reasonable period" for the supported spouse to become self-supporting is generally half the length of the marriage (Family Code 4320(l)). A marriage of 10 years or more is presumed to be of long duration, and the court keeps jurisdiction over support indefinitely (Family Code 4336). That does not mean support lasts forever. It means there is no automatic end date.
This estimate does not adjust for taxes. Under California law, spousal support is deductible by the payer and taxable to the recipient on the California return only for orders or agreements signed from 2019 through 2025. For those signed on or after January 1, 2026, California follows federal law: not deductible and not income.
Frequently Asked Questions
How is spousal support calculated in California?
For temporary support while a case is pending, many California courts use a guideline of about 40% of the higher earner's net income minus 50% of the lower earner's net income, after child support. Long-term support after judgment has no formula: the judge weighs the factors in Family Code 4320.
How long does spousal support last in California?
For marriages under 10 years, support often lasts about half the length of the marriage, measured from the wedding to the date of separation. For marriages of 10 years or more, the court keeps jurisdiction with no set end date, although support can still be reduced or ended later.
Is spousal support taxable in California?
It depends on when the order or agreement was signed. For agreements signed from 2019 through 2025, California lets the payer deduct it and taxes the recipient on the state return, even though the federal return does not. For agreements signed on or after January 1, 2026, California follows federal law: not deductible and not taxable.
Can spousal support be changed later?
Yes, unless the agreement says it cannot be modified. Either spouse can ask the court to change support when circumstances change, such as a job loss, retirement or a big change in income.
Does remarriage end spousal support in California?
Unless the parties agreed otherwise in writing, support ends when the supported spouse remarries or either spouse dies (Family Code 4337). Living with a new partner can also be grounds to reduce support (Family Code 4323).
This tool provides an educational estimate only and is not legal advice. Temporary support guidelines vary by county and are calculated with certified software that accounts for taxes. Final support is decided case by case under Family Code 4320. Talk to a family law attorney about your situation.