California Child Support Calculations
By Susan Buckner, J.D. | Legally reviewed by FindLaw Staff | Last reviewed February 21, 2025
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In California, courts base child support orders on the parent's income and the child's needs. California child support guidelines ensure that both parents support the child and that the child enjoys the same standard of living as before the parents divorced or separated.
The child support formula balances the amount of time the noncustodial parent spends with the child and the total net income of both parents. The theory is that the custodial parent contributes most of the child's basic needs. But, California law allows judges to adjust the support amount based on the parents' agreements or ability to pay.
California Guidelines for Calculating Child Support
In the early days of divorce and child support, one parent, usually the mother, had the majority of parenting time, and the other parent paid most or all the child support. Today, joint custody arrangements are the rule. Parents are likely to pay equal child support unless one parent earns significantly more than the other.
California child support calculations use a guideline formula to determine the amount of support the higher earner pays to the lower earner. This formula takes into account all required deductions from the parents' income,
Primary Considerations for Support Determinations
A child support case is separate from divorce or child custody. Either parent or the child's legal guardian may open a case with the Department of Child Support Services. The local child support agency manages the case in the child's county of residence. When a parent or guardian goes to court, they should have all relevant information to help the court determine the necessary amount of child support. You should get legal advice from a family law attorney to ensure you have all the necessary information.
FindLaw's child support checklist can help you gather the information your lawyer will need to help you in your child support case.
Determining Factors for Child Support
California Family Code Section 4053 states that both parents' primary duty is the care and support of their minor children. To determine the amount of support, courts may consider:
- Both parents' gross income, including money from any source, such as wages, rental income, pensions, trusts, and so on
- The number of children the parents have together
- The custody timeshare agreement, whether court-ordered or decided between the parents
- Health insurance considerations
- Mandatory payroll deductions, such as union dues, SSI, and income tax deductions
- Health care, child care, and other costs
In some situations, a judge may deviate from the guideline amount. If parents have agreed on a figure that meets all other legal requirements, the judge can accept that figure. If one parent makes a substantially higher or lower amount than the other, the judge may order a different support payment in the interest of fairness.
How Support Gets Calculated
The actual formula for calculating child support is CS = K[HN – (H%)(TN)].
- CS is the amount of child support.
- K is the total income of both parents.
- HN is the higher-earning parent's net monthly disposable income. "Disposable income" means the total income minus all required deductions such as state and federal income tax, employer health insurance premiums, other spousal support payments, etc.
- H% is the percentage of time the higher-earning parent spends with the child.
- TN is the combined net disposable income for both parents.
The formula may seem confusing and arbitrary, but California courts find it consistently results in fair and equitable support payments for most families. The Child Support Guideline Calculator provided by DCSS can give parents an idea of their support obligations, with the disclaimer that it is only an estimate until a judge issues a final order.
When Child Support Ends
Parents must support their child until (Family Code § 3901):
- The child graduates from high school or reaches the age of 19, whichever comes first
- The child legally marries if under 18
- The child legally emancipates
- The child enters military service
- The child dies
Parents may request, and judges may order, extended support for adult children with special needs who have no other means of earning a living (Family Code § 3910).
Related Resources
- Child Support Enforcement in California
- How Do I Get Child Support in California?
- California Child Support Modification
- California Child Support Payment
Get Legal Advice From a California Family Law Attorney
Child support is a very contentious part of divorce and separation. Even if you and your spouse have negotiated the rest of your divorce, you should consult a California family law attorney with any questions about your child support order or payments.
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