How Alimony Is Calculated in California: Temporary vs. Long-Term
California treats support during the divorce and support after it completely differently. Only one of them has a formula.
Temporary spousal support (while the divorce is pending) is usually set with a guideline: about 40% of the higher earner's net income minus 50% of the lower earner's, after child support. Long-term support after the judgment has no formula: a judge weighs the factors in Family Code 4320, and marriages of 10+ years have no set end date.
Temporary support: the 40/50 guideline
While a case is pending, courts need a fast, predictable number. Santa Clara County's Family Rule 3(C) states the guideline many courts use: 40% of the payer's net income minus 50% of the recipient's net income, calculated on income not already allocated to child support. Many other courts use the same or a similar formula in their support software, and some counties have their own. Check your local rules.
Example: the higher earner nets $10,000 a month and pays $1,500 in child support; the other spouse nets $3,000. Temporary support = 40% × $8,500 − 50% × $3,000 = $1,900 a month.
Long-term support has no formula
After judgment, courts are not supposed to reuse the temporary guideline. Instead a judge weighs the circumstances in Family Code 4320, including:
- each spouse's earning capacity and the job market for their skills;
- the standard of living during the marriage;
- contributions to the other spouse's education or career;
- the payer's ability to pay, and each spouse's assets and debts;
- the length of the marriage, age and health;
- documented domestic violence;
- tax consequences and the balance of hardships;
- the goal that the supported spouse becomes self-supporting within a reasonable time.
That is why two couples with identical incomes can walk out with different orders.
How long alimony lasts: the 10-year rule
For marriages shorter than 10 years (measured from the wedding to the date of separation, not the divorce), a "reasonable period" for the supported spouse to become self-supporting is generally half the length of the marriage (Family Code 4320(l)). A six-year marriage often means about three years of support.
A marriage of 10 years or more is presumed to be of long duration (Family Code 4336). The court keeps jurisdiction indefinitely, so there is no automatic end date, though support can still be reduced or ended later as circumstances change.
How spousal support is taxed
Federal law stopped letting payers deduct alimony for agreements signed after 2018. California did not follow that change for years: for orders and agreements signed from 2019 through 2025, the payer still deducts support on the California return and the recipient reports it as California income. Under SB 711, agreements signed on or after January 1, 2026 follow the federal rule in California too: no deduction, no income.
Ending or changing support
Unless the parties agreed otherwise in writing, support ends when the supported spouse remarries or either spouse dies (Family Code 4337). Either spouse can ask the court to modify support after a material change, such as job loss, retirement, or the supported spouse living with a new partner (Family Code 4323).
Estimate temporary support
Our Spousal Support Calculator applies the 40/50 guideline with child support deducted first, and shows what the length of your marriage means for duration.
Frequently Asked Questions
How is alimony calculated in California?
Temporary alimony during the case is usually estimated at 40% of the higher earner's net income minus 50% of the lower earner's net income, after child support. Final (long-term) alimony has no formula: the judge weighs the factors in Family Code 4320.
How long do you have to be married to get alimony in California?
There is no minimum. Any spouse can request support, but the length of the marriage affects how long it lasts: generally about half the marriage for marriages under 10 years, and no set end date for marriages of 10 years or more.
What is the 10-year rule for alimony in California?
A marriage of 10 years or more, from the wedding to separation, is presumed to be of long duration. The court then keeps jurisdiction over support indefinitely instead of setting an automatic end date.
Is alimony taxable in California?
For agreements signed from 2019 through 2025, yes on the California return (deductible for the payer, income for the recipient), even though it is not on the federal return. For agreements signed on or after January 1, 2026, California follows federal law and it is neither deductible nor taxable.
Does cohabitation end alimony in California?
Not automatically, but when the supported spouse lives with a romantic partner, the law presumes they need less support, which can justify reducing or ending it (Family Code 4323).
This article is for general information only and is not legal advice. Guidelines vary by county and final support is decided case by case. Consult a family law attorney.