Child Support in Concord and Contra Costa County, California

Contra Costa County, seated in Martinez and made up of communities like Concord, Richmond, Antioch, Walnut Creek, and San Ramon, handles child support matters through the Superior Court of California, County of Contra Costa, and the Contra Costa County Department of Child Support Services (DCSS). Family law and child support cases are heard at the Peter L. Spinetta Family Law Center on Pine Street in Martinez, while DCSS runs enforcement and collection work from its own Martinez office. Families throughout the county's varied cities, from the industrial waterfront towns to the inland suburbs, all funnel into this same Martinez based system.

California sets child support the same way in Contra Costa County as it does everywhere else: through a statewide uniform guideline formula found in Family Code section 4055. The formula combines both parents' net disposable incomes with the timeshare, the percentage of time the child spends in each parent's care, into an amount the law presumes to be correct.

There are two ways a support order gets put in place here. A parent already involved in a divorce, parentage, or custody case can file a Request for Order (Form FL-300) with an Income and Expense Declaration (Form FL-150) at the Family Law Filing Counter of the Peter L. Spinetta Family Law Center in Martinez. Alternatively, the Contra Costa County Department of Child Support Services, the local branch of the statewide Department of Child Support Services, can open a case on its own to establish and enforce support. The forms are the same across California; the local piece in Contra Costa is that both paths, whether the courthouse or the DCSS office, run through Martinez.

Before you file, it's worth checking roughly what to expect. Our free California child support calculator uses the same income and timeshare inputs the court relies on. If both parents already agree on an amount, a written stipulation can be submitted for a judge's signature instead.

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 Contra Costa 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 Contra Costa County

Child support in Contra Costa County is handled through the Superior Court of California, County of Contra Costa, 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 Contra Costa County Superior Court (official California Courts finder)

Local notes for Contra Costa County

Contra Costa County hears family law and child support matters at the Peter L. Spinetta Family Law Center, 751 Pine Street in Martinez, which houses most of the county's family law courtrooms along with the Family Law Filing Counter where support paperwork is submitted. The Contra Costa County Department of Child Support Services (DCSS), based separately at 50 Douglas Drive in Martinez, handles establishing and enforcing support orders and is the office to contact if you want the county to open a case without a private family law filing. The court also accepts electronic filing for family law and DCSS cases through the statewide Odyssey eFileCA portal, so confirm current filing options directly with the court before submitting paperwork by mail or in person.

The court's Family Law Facilitator's Office, Contra Costa's version of a self-help center, assists parents representing themselves with completing Form FL-150 and related documents and explains the general filing process, but staff cannot give legal advice specific to your case. The office offers in-person drop-in assistance at the Martinez courthouse on weekday mornings along with online chat and scheduled appointments. Because the guideline number is driven directly by the income figures reported, completing that form accurately is the single biggest factor in the outcome.

As under California law statewide, child support in Contra Costa County 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 request a modification later if income or the parenting timeshare changes meaningfully.

Official child support resources in Contra Costa County

Contra Costa County's family law and child support cases are heard at the Peter L. Spinetta Family Law Center, 751 Pine Street in Martinez, which houses five of the county's seven family law courtrooms and the Family Law Filing Counter where Request for Order and related paperwork is filed.

Enforcement and collection work is handled separately by the Contra Costa County Department of Child Support Services (DCSS), based at 50 Douglas Drive, Suite 100, in Martinez. DCSS establishes paternity, sets support amounts, and collects and distributes payments, and can open a case on its own even when no other family law matter is pending.

Parents representing themselves can get free procedural help from the court's Family Law Facilitator's Office, which offers in-person drop-in assistance in Martinez on weekday mornings plus online chat and scheduled appointments for help with support, custody, and related paperwork. The court also accepts electronic filing for family law and Department of Child Support Services cases through the statewide Odyssey eFileCA portal.

• Contra Costa County Department of Child Support Services
• Peter L. Spinetta Family Law Center
• Family Law Facilitator (Self-Help)
• Court E-Filing Services (Odyssey eFileCA)

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

Contra Costa County Child Support FAQs