Child Support in San Rafael and Marin County, California

Marin County is a Bay Area county, serving families in San Rafael, Novato, and Mill Valley. Child support cases are handled by the Superior Court of California, County of Marin and the county's Local Child Support Agency.

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 Marin 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.

Because the number turns on income and timeshare, estimating early helps. Our free California child support calculator gives you a starting figure, and parents who agree can submit a written stipulation for a judge to sign.

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 Marin 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 Marin County

Child support in Marin County is handled through the Superior Court of California, County of Marin, 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 and local agency office details change over time, confirm current details using the official California Courts court finder:

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

Local notes for Marin County

In Marin 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.

Marin County offers self-help resources that assist self-represented parents with Form FL-150 and court procedure, though staff cannot give legal advice about your circumstances. Since the guideline amount depends on the income figures you provide, completing the Income and Expense Declaration accurately and completely matters most.

Child support in California generally continues until the child turns 18, or 19 if the child is still a full-time high school student living at home and not self-supporting. Either parent can ask the court to modify support when income or the parenting timeshare changes meaningfully.

Official child support resources in Marin County

Family law matters in Marin County, including child support, are handled by the Superior Court of California, County of Marin, through its Unified Family Court division. The court's family law division sits at the Civic Center, Hall of Justice, in San Rafael, the county seat.

The court's Legal Self-Help Center, which includes the Family Law Facilitator's Office, is also located at the Civic Center, Hall of Justice, in San Rafael. It assists self-represented parents with child support, child custody, divorce, and paternity paperwork, including completing the Income and Expense Declaration (Form FL-150), though staff cannot give legal advice about a specific case.

Marin County's local child support agency, part of the statewide Department of Child Support Services system, operates from an office in Novato. It can open a case to establish, collect, and enforce child support.

• Marin County Superior Court: Unified Family Court
• Marin County Superior Court: Legal Self-Help Center
• Marin County Superior Court: Family Court Services
• California Department of Child Support Services: Find My Local Agency

Local details reviewed July 2026. Offices and locations can change, so confirm with the official sites above before you file.

Marin County Child Support FAQs