California Child Support — Calculator, Laws & Guide (2026)

Understanding California child support laws helps both custodial and non-custodial parents know their rights and obligations. This comprehensive California child support guide covers how payments are calculated, what income counts, when support can be modified, and how orders are enforced. Whether you are going through a divorce, seeking a modification, or dealing with non-payment, this guide explains California’s child support system in plain language.

Verified against California statutes and federal OCSE guidelines as of April 2026.

California Child Support Overview

California uses the income shares model for calculating child support. This model is based on the principle that children should receive the same proportion of parental income they would have received if the family were intact. Both parents’ incomes are combined, and the support obligation is divided proportionally.

California uses the statewide uniform guideline formula: CS = K[HN – (H%)(TN)], where K = amount of both parents’ income allocated for child support (varies by number of children and combined income), HN = high earner’s net monthly disposable income, H% = approximate percentage of time the high earner has primary physical responsibility for the children, and TN = total net monthly disposable income of both parties. More children increase the K factor. The formula automatically accounts for parenting time-share so the parent with more custody time receives more support. California also applies a Low Income Adjustment (LIA) when the obligor’s net disposable income falls below full-time minimum wage — the 2026 LIA threshold is 2929 per month based on the California minimum wage of 16.90 per hour.

How California Calculates Child Support

The California child support calculation considers multiple factors:

1. Determine each parent’s gross income — wages, salary, commissions, bonuses, self-employment income, investment income, and other sources.
2. Calculate combined parental income — add both parents’ adjusted gross incomes together.
3. Apply the guideline schedule — California’s guidelines provide a base support amount based on combined income and number of children.
4. Prorate between parents — each parent’s share is proportional to their percentage of the combined income.
5. Add healthcare and childcare costs — these are added to the base amount and divided proportionally.
6. Apply adjustments — parenting time credits, other child obligations, and special circumstances may adjust the final amount.

Online calculator: Use our child support estimator below to calculate your estimated obligation.

What Counts as Income in California

Annual gross income from whatever source derived under Family Code section 4058, including: salaries, wages, commissions, bonuses, rents, royalties, dividends, pensions, interest, trust income, annuities, workers’ compensation benefits, unemployment insurance benefits, disability insurance benefits, social security benefits, and spousal support received from a non-party. Business income is gross receipts minus required operating expenditures. Employee benefits and self-employment benefits may be included at court discretion. Excluded: child support received and public assistance based on need. Net disposable income is then calculated per Family Code section 4059 by deducting state and federal income taxes, FICA contributions, mandatory union dues, mandatory retirement contributions, health insurance premiums, state disability insurance, and hardship deductions.

Imputed income: YES. Under Family Code section 4058(b), courts may impute earning capacity to a voluntarily unemployed or underemployed parent. Courts consider: assets, residence, employment and earnings history, job skills, educational attainment, literacy, age, health, criminal record and other employment barriers, record of seeking work, local job market conditions, availability of employers, and prevailing earnings in the local community. Important exception: incarceration or involuntary institutionalization shall not be treated as voluntary unemployment for establishing or modifying support orders.

Deviation factors: Under Family Code section 4057, courts may deviate from the guideline formula for special circumstances including: parents have different time-sharing arrangements for different children; both parents have substantially equal time-sharing and one has a much higher or lower percentage of income used for housing; children have special medical or other needs requiring support above the formula amount; a child has more than two legal parents; the obligor qualifies for a Low Income Adjustment and guideline support exceeds 50% of net income after the adjustment (added effective September 1, 2024). The court must state deviation findings in writing or on the record.

Healthcare & Childcare in California Child Support

Health insurance: Courts must order health insurance coverage for the children if available at reasonable cost through a parent’s employment or group plan under Family Code section 3751. Reasonable uninsured healthcare costs for the children are a mandatory add-on to guideline support under Family Code section 4062(a). These costs are divided equally between parents unless one parent requests and documents a different apportionment. Emergency medical costs that precluded use of insurance or preferred providers are also addressed.

Childcare costs: Childcare costs related to employment or reasonably necessary education or training for employment skills are mandatory add-ons to guideline child support under Family Code section 4062(a). These costs are added on top of the base guideline amount and divided equally between parents, unless one parent presents documentation showing a different apportionment is more appropriate. The costs must be actually incurred.

When Does California Child Support End?

In California, child support generally ends when the child reaches 18 years old. If the child is still a full-time high school student at 18 and cannot support themselves, support continues until graduation or age 19, whichever occurs first. Support also terminates upon marriage, military enlistment, emancipation, or death. Support may continue past 18/19 for an incapacitated adult child who cannot be self-supporting, per Family Code section 3910.. However, support may continue or end earlier based on:

• The child graduates from high school (if still a minor)
• The child becomes emancipated (marriage, military service, self-supporting)
• The child has special needs requiring ongoing support
• College support: NO. California does not require parents to contribute to college or post-secondary education costs through child support orders. Support terminates at 18 (or 19 if still in high school). Parents may voluntarily agree to include college support in a marital settlement agreement or stipulation, but courts cannot order it.

Modifying California Child Support

When to modify: A modification may be requested when the recalculated support amount would differ from the current order by 20 percent or 50 dollars, whichever is less. Other qualifying changes include: substantial increase or decrease in either parent’s income, change in custody arrangement, change in time-sharing percentage, new support obligations for other children, or job loss. Cases are also eligible for review every three years regardless of changed circumstances. If the parties previously stipulated to a below-guideline amount, either party may request modification at any time without showing changed circumstances.

How to modify: Either parent may file a motion to modify with the Superior Court (family law division) or request a review through their local child support agency (LCSA). If both parents agree, they may file a Stipulated Agreement using Judicial Council form FL-350. If they disagree, the court conducts a hearing and decides based on evidence. Once modified, an Amended Income Withholding Order (FL-195) must be obtained. The modification is effective from the date of filing, not retroactively.

Either parent can request a modification. Changes are typically not retroactive to before the date of filing the modification request.

California Child Support Enforcement

California has multiple tools to enforce child support orders when a parent fails to pay:

• Earnings assignment orders/wage garnishment (up to 50% of disposable income
• or 65% for arrears under Family Code sections 5100-5110); federal and state income tax refund intercept (through IRS and Franchise Tax Board); driver’s license suspension (after 30 days delinquency with notice); professional and occupational license suspension; passport denial (when arrears exceed 2500
• through federal Passport Denial Program); bank account levy and freeze; property liens on real estate and vehicles; lottery winnings intercept; unemployment and disability benefits intercept; credit bureau reporting; contempt of court (penalties include jail
• fines
• and community service — used as last resort when other tools fail). All payments are processed through a centralized State Disbursement Unit as required by federal law.

Contact California Department of Child Support Services (DCSS), operating through a statewide network of 47 local child support agencies at the county level at https://childsupport.ca.gov/ for enforcement assistance.

Additional California rules: California is the only state that uses its guideline formula to adjust for low-income obligors rather than a self-support reserve (SSR) — the Low Income Adjustment (LIA) under Family Code section 4055(b)(7) creates a rebuttable presumption that the obligor is entitled to a reduction when net disposable income is below full-time minimum wage (2929 per month in 2026 based on 16.90 per hour). California’s K factor in the formula automatically adjusts the percentage of combined income devoted to support based on the number of children and total income level. Arrears accrue 10 percent annual interest that courts cannot waive. The guideline formula gives direct credit for parenting time-share rather than using a separate shared-custody adjustment. Hardship deductions are available under Family Code section 4071 for extraordinary healthcare expenses, uninsured catastrophic losses, minimum basic living expenses of children from other relationships, and other circumstances the court deems appropriate.

Official Sources & Resources

• California Department of Child Support Services (DCSS), operating through a statewide network of 47 local child support agencies at the county level: https://childsupport.ca.gov/
• Federal OCSE: acf.hhs.gov/css
• Cornell LII — Child Support: law.cornell.edu
• California Guidelines Statute: California Family Code sections 4050 through 4076 (Division 9, Part 2, Chapter 2, Article 2 — Statewide Uniform Guideline), with the primary formula at Family Code section 4055, income definition at section 4058, net disposable income deductions at section 4059, and mandatory add-ons at sections 4061-4062

Last verified April 2026. Contact us if you notice outdated information.

Estimate Your Child Support

Use our free child support estimator to calculate estimated monthly payments. Enter both parents’ incomes, number of children, and custody arrangement to see a personalized breakdown based on your state’s formula.

Related Guides

• California Divorce Process Guide
• California Child Custody Guide
• California Alimony Guide
• All Child Support Guides