California Guideline Child Support Calculator

Under federal law, every single state is required to have a formula that determines the correct amount of child support that should be awarded. California is no exception. The California Guideline Child Support Calculator is based on California Child Support Guidelines and can be used to estimate the amount of child support that may be ordered in your case. It is important to remember the Court Commissioner or Family Law Judge has the final authority to determine the amount of a child support order. This calculator provides only an estimate and is not a guarantee of the amount of child support that will be ordered. Other factors may affect the amount of child support awarded.

However, just because California uses a formula, doesn’t mean using the formula is easy. As expert California family lawyers, we often see self-represented parties, attorneys, and even judges overlook some important tweaks to the formula that can result in substantial changes in the ultimate support amounts awarded. We will address three of these factors below:

1) Discounting of Social Security/California SDI

The vast majority of California residents pay into social security. Many, however, do not. Those who contribute to a federal, state, or city pension do not contribute to social security or to California SDI. Unless the proper adjustment is made, any program used to calculate child support will assume that these individuals contribute to these programs. The social security contribution is rather significant: individuals who pay into the system contribute 6.2 percent of their income up to $117,000 to social security. Without making the proper adjustment, any child support program may incorrectly reduce an individual’s income available support by the same percentage. This can result in a change of hundreds of dollars per month.

2) 401k deductions as an adjustment to income

Those who are required to contribute to mandatory retirement plans (incidentally the same individuals that typically don’t contribute to social security and California SDI in item #1 above) are entitled to a deduction for those contributions under Family Code section 4059(c). This a well-known deduction to most lawyers and judges.

However, those who contribute to employer-sponsored 401k plans also require an adjustment to their incomes. If one consistently contributes to a traditional 401k plan, those amounts (up to $18,000 per year, not counting catch up contributions for older individuals) are tax deductible to that individual and could result in a substantial increase to the contributor’s income available for support at the end of the year. This is one of the most overlooked adjustments to child support that we see.

3) Itemized deductions (home mortgage interest and property tax deduction)

Those who are not represented by an attorney typically overlook these very important deductions. Most child support programs will help with this. For example, many of the child support programs will automatically assume high earners in California will itemize (because they pay substantial California state income tax), but these programs can’t automatically input someone’s home mortgage interest and property tax deductions for obvious reasons. The home mortgage interest and property tax deductions can be considerable and can greatly increase an individual’s income available for support.


Our office is well-versed in handling child support matters. Nancy J. Bickford is the only Certified Family Law Specialist (CFLS) in San Diego County who is also a licensed Certified Public Accountant (CPA) with a Master of Business Administration (MBA). Don’t settle for less when determining your rights. Call 858-793-8884 in Del Mar, Carmel Valley, North County or San Diego.

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