California Guideline Child Support

California courts determine child support according to a complicated but standardized “guideline” formula found in Family Code § 4055.

Principles of Guideline Child Support

California guideline seeks to encourage fair and efficient settlements of conflicts between parents and seeks to minimize the need for litigation. In implementing the statewide uniform guideline, the Court must adhere to the following principles:

  • Guideline seeks to place the interests of children as the top priority.
  • Guideline child support is presumptively correct. Only under special circumstances should child support fall below the guideline However, the presumption is rebuttable in some rare cases.
  • Child support orders must ensure that children actually receive fair, timely, and sufficient support reflecting the high standard of living and child raising costs in California.

California Guideline Factors

California guideline child support considers several factors, including:

  • Custodial Timeshare: Custodial timeshare is the amount of time the child spends with each parent. Whether parents share joint custody or one parent has “sole” physical custody, there is typically some custodial timeshare percentage that applies based on visitation.
  • Annual gross income: Gross income includes income from ALL sources, including but not limited to: wages, salaries, bonuses, commissions, royalties, rents, dividends, pensions, interest, trust income, annuities, workers’ compensation, unemployment, disability, social security and spousal support from another marriage.
  • Earning capacity: If one parent is unemployed, the court MAY consider that parent’s earning capacity in lieu of actual income. The court does this in the best interest of the children, so that neither parent can voluntarily avoid employment. If earning capacity is imputed to the custodial parent, however, the supporting parent generally must contribute to childcare costs.
  • Tax Factors: Gross income is reduced by actual tax liability, as determined by the guideline calculation software. Tax liability is based on each parent’s tax filing status, number of exemptions and qualifying deductions, and may differ from the amount withheld from paycheck withholding.
  • Allowable child support deductions: Each parent is allowed deductions for state and federal income tax liability, FICA, mandatory union dues, mandatory retirement contributions, pre-tax health insurance premiums for the parent and child, any child support or spousal support already being paid, necessary job-related expenses, and certain California adjustments to income. Further deductions, known as “hardships”, may be available for extraordinary medical expenses or catastrophic losses.

Child Support Add-Ons

Certain other expenses are considered child support “add-ons”. Some expenses are mandatory child support add-ons, meaning that the court must include them in guideline child support if the expenses exist. These expenses include childcare costs related to employment or reasonably necessary job training and reasonable uninsured health care costs for the children. Other child support add-ons are at the court’s discretion. These include costs related to “special” needs or education of the children and travel expenses for visitation.


Lisa L. Fiance, Esq.Lisa L. Fiance, Esq. is a family law attorney, divorce mediator, and the owner of Epiphany ADR in beautiful Oceanside, CA. The information contained in this article is intended as general information and does not constitute legal advice. If you have legal questions about child support, you should consult with legal counsel in the state in which you reside.