Child Support in Sonoma County, California

Sonoma County sits in the Bay Area's northern reach. Its family courts and Local Child Support Agency handle support matters for families in Santa Rosa, Petaluma, and Rohnert Park, all through the Superior Court of California, County of Sonoma.

Child support in California follows one statewide guideline formula (Family Code section 4055), based mainly on both parents' net disposable incomes and the share of time the child spends with each parent, the timeshare. The guideline amount is presumed correct, and it works no differently in Sonoma County than anywhere else in California.

There are two paths to a support order. One parent can file a Request for Order (Form FL-300) along with an Income and Expense Declaration (Form FL-150) inside a divorce, parentage, or custody case, or the Local Child Support Agency (part of the California Department of Child Support Services) can open a case to set up and enforce support. Only the local logistics differ from county to county.

The result depends on accurate income and timeshare, so an estimate up front is useful. Try our free California Guideline Child Support Calculator at /tools/california-child-support-calculator, and note that parents who agree can submit a stipulation for a judge to sign instead of going to a hearing.

How child support is calculated in California

California sets child support with a statewide uniform guideline (Family Code section 4055) that applies the same way in Sonoma County as everywhere else. The formula is based mainly on two things:

1. Both parents' net disposable incomes.
2. The percentage of time the child spends with each parent (the timeshare).

The guideline amount is presumed to be correct, and courts use a calculator to run the numbers. Because the result depends on accurate income, the Income and Expense Declaration (Form FL-150) you file is what drives your number.

Where child support cases are handled in Sonoma County

Child support in Sonoma County is handled through the Superior Court of California, County of Sonoma, with the county seat in Santa Rosa, and the county's Local Child Support Agency, which is part of the California Department of Child Support Services. There are two common paths:

1. Either parent files a Request for Order (Form FL-300) with an Income and Expense Declaration (Form FL-150) inside a divorce, parentage, or custody case.
2. The Local Child Support Agency opens a case to establish, collect, and enforce support, often at no cost to the parents.

Because courthouse locations and the local agency office change over time, confirm current details using the official California Courts court finder:

Find the Sonoma County Superior Court (official California Courts finder)

Local notes for Sonoma County

In Sonoma County, family law matters run through the Superior Court and the county's Local Child Support Agency handles agency cases. Use the official California Courts court finder to confirm the right courthouse, and look up the agency through the California Department of Child Support Services, before filing.

The county's self-help center helps parents who represent themselves complete Form FL-150 and understand court procedure, but staff cannot give legal advice about your specific case. Because the guideline result is driven by the income you report, filling out the Income and Expense Declaration accurately is the most important step.

Under California law, support usually lasts until the child turns 18, or 19 if the child remains a full-time high school student living at home and is not self-supporting. When circumstances change, such as a shift in income or timeshare, either parent can request a modification.

Sonoma County Child Support FAQs