California Child Support Modification

Statutes

• Cal. Fam. Code § 4055 — Statewide Uniform Child Support Guideline

  California child support is calculated by the formula CS = K[HN - (H%)(TN)], where HN is the high earner's net monthly disposable income, H% is the approximate percentage of time the high earner has or will have primary physical responsibility for the children, and TN is both parties' total net monthly disposable income. K equals one plus H% (if H% is 50 percent or less) or two minus H% (if H% is over 50 percent), times a fraction set by income bracket (for example 0.250 when total net disposable income is $5,001-10,000 a month), and the result is multiplied for additional children (1.6 for two children, 2 for three). If the result is positive the higher earner pays it to the lower earner; if negative, the lower earner pays the absolute value to the higher earner. When the obligor's net disposable income is below the monthly gross income of full-time minimum wage (40 hours a week, 52 weeks a year), there is a rebuttable presumption that the obligor is entitled to a low-income adjustment, which may be rebutted by evidence that applying it would be unjust and inappropriate in the particular case. This version of the formula became operative September 1, 2024. In a default, or when a party fails to appear, and there is no evidence of time-share, H% is set at zero if the noncustodial parent is the higher earner or 100 if the custodial parent is the higher earner, and the non-defaulting party's statement of the time-share is sufficient evidence.

• Cal. Fam. Code § 4057 - Guideline Amount Presumed Correct; Rebuttal Factors

  The amount produced by the guideline formula in § 4055(a) is presumed to be the correct child support. It is a rebuttable presumption affecting the burden of proof, overcome only by admissible evidence that applying the formula would be unjust or inappropriate because a listed factor is found by a preponderance of the evidence, and the court must state the required information in writing or on the record. The factors are a stipulated different amount, a deferred sale of the family home whose rental value exceeds its carrying costs, an extraordinarily high-income payer whose formula amount would exceed the children's needs, a parent not contributing to the children's needs at a level matching that parent's custodial time, a low-income payer whose formula amount exceeds 50 percent of net disposable income, or special circumstances (such as different time-shares for different children, equal time-share with very different housing costs, special medical or other needs, or more than two parents). This version became operative September 1, 2024.