California calculates alimony using each spouse’s net disposable income, not gross income. Net disposable income is what’s left after specific mandatory deductions come out of total earnings, and it’s the figure the court plugs into the guideline formula for temporary spousal support during a pending divorce. For long-term support set in the final judgment, net income still matters, but it becomes one factor among many the judge weighs rather than the input to a formula.
What Gross Income Includes
The calculation starts with gross income. Under California Family Code Section 4058, gross income is defined broadly and pulls in earnings from nearly every source:
- Salaries, wages, commissions, and bonuses from employment
- Self-employment earnings after documented business expenses
- Investment income, including interest, dividends, and rental property
- Retirement distributions, Social Security benefits, and disability payments
That total is the top of the ledger. Nothing has been subtracted yet, and no court would set support from this figure alone, because it doesn’t reflect what either spouse actually has to spend.1California Legislative Information. California Family Code – Section 4058
Deductions That Turn Gross Into Net
Family Code Section 4059 lists what comes out to get to net disposable income. These are mandatory, not discretionary, and voluntary spending doesn’t qualify:
- State and federal income tax liability
- Social Security and Medicare payroll taxes
- Mandatory union dues
- Mandatory retirement contributions required as a condition of employment
- Health insurance premiums
- Child or spousal support already being paid under another court order
Car payments, credit card balances, voluntary 401(k) contributions above what an employer requires, and personal savings all stay in the net figure. They’re expenses the spouse chose, and the court doesn’t shield them from the support calculation.2California Legislative Information. California Family Code – Section 4059
The number left after these mandatory deductions is what the court treats as available for support.
How Net Income Drives Temporary Support
While the divorce is pending, most California courts order temporary spousal support using a guideline formula that runs directly on net monthly income. The common version:
Support equals 40% of the higher earner’s net monthly income, minus 50% of the lower earner’s net monthly income.
Take a couple where Spouse A has $6,000 in net monthly income and Spouse B has $4,000. Forty percent of $6,000 is $2,400. Fifty percent of $4,000 is $2,000. The temporary support order would be $400 per month from A to B.3Judicial Branch of California. Temporary Spousal Support
Local courts sometimes use slightly different percentages, and most judges run the numbers through software like DissoMaster or Xspouse rather than doing arithmetic on the bench. The formula is a starting point. A judge can move off it based on the facts of the case, but the input that starts the calculation is always net, never gross.
How Net Income Fits Into Long-Term Support
Temporary support and long-term support work differently. When the divorce is finalized, there is no formula. Family Code Section 4320 lists more than a dozen factors the judge must consider to reach an amount that’s “just and reasonable”:
- The marital standard of living
- Each spouse’s earning capacity
- Career sacrifices made during the marriage, especially time spent on domestic duties or supporting the other spouse’s career
- The paying spouse’s ability to pay, including income, assets, and obligations
- The length of the marriage
- Age and health of each spouse
- Any documented history of domestic violence
- Tax consequences of the support order
- The goal of the supported spouse becoming self-supporting
Net income shows up inside “ability to pay” and inside the tax-consequences factor, but it doesn’t control the result on its own.4California Legislative Information. California Family Code – Section 4320 Two couples with identical net incomes can end up with very different long-term orders based on the length of the marriage, career sacrifices, or health issues.
Vocational Evaluations
When one spouse argues the other could be earning more, or when the supported spouse claims an inability to work, the court can order a vocational evaluation. A vocational expert reviews education, work history, transferable skills, and the local job market to estimate realistic earnings. The report gives the judge objective data, and it often reshapes the net-income figure the court uses.
Imputed Income When a Spouse Underearns
Because the calculation depends on net income, a spouse could try to lower support by quitting a job or taking a pay cut. California courts address this by imputing income. If a spouse is voluntarily unemployed or working below their capacity, the judge can assign an earning figure based on what that person could reasonably make given skills, education, and work history. The court then treats that imputed number as the starting point for the net calculation.1California Legislative Information. California Family Code – Section 4058
Imputation cuts both ways. A supporting spouse who takes a low-paying job to reduce their obligation can be treated as still earning their prior income. A supported spouse who refuses to look for work despite being able to can have income assigned to them, which lowers the support they receive.
Proving the Numbers: Financial Disclosures
The net-income figure only works if the court has accurate numbers to work with. Both spouses must file and exchange an Income and Expense Declaration (Form FL-150). Under California Rules of Court Rule 5.260, this form is required for any hearing involving spousal support, and it must have been completed within the past three months to be considered current.5Judicial Branch of California. California Rules of Court Rule 5.260 – General Provisions Regarding Support Cases
On the FL-150, each spouse lists every income source, itemizes monthly expenses, and discloses assets and debts. Supporting documentation isn’t optional. Pay stubs from the last two months and the most recent federal tax return must be brought to the hearing.6California Courts. FL-150 Income and Expense Declaration
Penalties for Hiding Income
Family Code Section 2107 gives the court real teeth on disclosure. A spouse who doesn’t comply faces sanctions that include paying the other side’s attorney’s fees and investigation costs, and the sanctions must be “sufficient to deter repetition of the conduct.” In serious cases, the judgment itself can be set aside, and intentional fraud can reopen the case after the divorce is final.7California Legislative Information. California Family Code – Section 2107 A spouse who’s caught hiding assets also loses credibility on every other contested issue in the divorce, from custody to property division.
If you’re preparing for a spousal support hearing in California, the practical takeaway is this: gather your pay stubs, tax returns, and records of every mandatory deduction. The gross number on your W-2 is not what the court will use. What matters is what’s left after taxes, required insurance and retirement, and any existing support orders come out, because that’s the figure the guideline formula and the Section 4320 analysis both rely on.