How to File for Child Support in California Without an Attorney
Child support in California is not a negotiation — it is a formula. The court takes both parents' incomes, the percentage of time each parent has with the child, and certain deductions, and produces a number. Your job is to give the court accurate information. SharpeSystem helps you do that without an attorney.
How support is calculated
California uses the Dissomaster formula — a statewide calculation that considers each parent's gross income from all sources, the percentage of time the child spends with each parent (timeshare), tax filing status, mandatory deductions like union dues and health insurance, and hardship deductions in limited circumstances. The formula produces a monthly support amount. Judges rarely deviate from it.
The forms you need
File FL-300 to open a Request for Order for child support. Attach FL-150 — Income and Expense Declaration — which is the form that captures your financial information for the formula. If you are also asking for custody orders, attach FL-311. If both parents agree on an amount, you can use FL-350 (Stipulation to Establish Child Support) instead of going through a hearing.
What the court needs from you
Accurate income information — pay stubs, tax returns, bank statements. The court takes financial disclosure seriously. If you underreport income or omit sources, it will come out at the hearing. The other parent's attorney or the court can subpoena records. Be accurate from the start.
After the order is issued
Once a support order is entered, it is immediately enforceable. The court can order wage garnishment — the money comes directly out of the paying parent's paycheck before they see it. Non-payment can result in license suspension, tax refund interception, and contempt of court. The order must also be registered with the state using FL-355.
Modifying support later
Child support can be modified if there is a significant change in circumstances — a job loss, a substantial income increase, or a change in custody timeshare. File a new FL-300 requesting the modification. Support does not change automatically — you have to go back to court.
Filing fee
Filing FL-300 costs $435 to $450. Fee waivers available via FW-001.
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