Can child support be modified if my income changes?

What the Law Says

California law allows child support orders to be changed when there’s been a 'material change in circumstances' — such as a significant increase or decrease in income. The court must recalculate support using the state’s guideline formula unless both parents agree otherwise.

A modification request can be filed by either parent — or by the local child support agency — whenever there’s been a substantial change in income, custody, or other factors affecting the original order.

The law does not require a specific percentage change in income, but courts often consider a change of at least 10–15% significant. However, case law and administrative guidance emphasize that even smaller changes may qualify if they meaningfully affect the child’s needs or the paying parent’s ability to pay.

You must file a formal Request for Order (Form FL-300) with the court and serve it on the other parent. Temporary modifications are not allowed — only the court can change an existing order.

Statutory Text

A child support order may be modified or terminated upon a showing of changed circumstances.

— Family Code § 3651(a) — Modification or termination of order

Statutory Text

The court shall apply the statewide uniform guideline… and shall issue a child support order in accordance with that guideline.

— Family Code § 4053 — Guideline principles

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