How to change child support in Washington

The rule for changing support, the forms, and a ready letter to the agency.

Checked against official sources: Oct 25, 2026.

Short answer

To modify an order means to change the amount by a new order. You can ask to change support at any time if circumstances have substantially changed (quitting a job or cutting hours on purpose is not enough by itself).

Agency review
Every 3 years if a parent asks (federal law)
First form
FL Modify 501 Petition to Modify Child Support

When you can ask for a change in Washington

You can ask to change support at any time if circumstances have substantially changed (quitting a job or cutting hours on purpose is not enough by itself). After 1 year, you can ask without a substantial change if the order causes severe economic hardship or a child needs support past 18 to finish high school. After 24 months since the order or last change, you can ask for an adjustment based on changes in either parent's income or in the economic table. DCS can seek a change if the order is at least 15% above or below the standard calculation.

Law: RCW 26.09.170

Can I ask for a change? Check your situation

Washington's rule: You can ask to change support at any time if circumstances have substantially changed (quitting a job or cutting hours on purpose is not enough by itself). After 1 year, you can ask without a substantial change if the order causes severe economic hardship or a child needs support past 18 to finish high school. After 24 months since the order or last change, you can ask for an adjustment based on changes in either parent's income or in the economic table. DCS can seek a change if the order is at least 15% above or below the standard calculation.

Law: RCW 26.09.170

Until a new order is made, the current amount is still owed. A change can count only from the date the other parent gets notice of your request, so ask soon.

Law: 42 U.S.C. 666(a)(9)

How to ask in Washington: If you have a DCS case, ask DCS to review your order (administrative orders through DCS; court orders through the county prosecutor's office). Or file in superior court: Petition to Modify Child Support (FL Modify 501) for a substantial change, or Motion to Adjust Child Support Order (FL Modify 521) for the 24-month adjustment.

How a change is made in Washington

If you have a DCS case, ask DCS to review your order (administrative orders through DCS; court orders through the county prosecutor's office). Or file in superior court: Petition to Modify Child Support (FL Modify 501) for a substantial change, or Motion to Adjust Child Support Order (FL Modify 521) for the 24-month adjustment.

Write to the child support agency to ask for a review: Ask the agency to review (change) your order

What changed in 2024–2026 in Washington

2025 c 272 (effective Jan. 1, 2026) replaced the economic table (now presumptive up to $50,000 combined monthly net income), raised the self-support reserve and the presumptive-minimum threshold to 180% of the federal poverty guideline, and kept the $50 per child minimum. A further amended version of RCW 26.09.170 takes effect April 1, 2027, adding abatement to $50 per child per month while a paying parent is in court-ordered behavioral health treatment. The state support schedule forms (WSCSS) were updated in 2026.

Jail, prison and support

State guidelines may not treat time in jail or prison as choosing not to work, when support is set or changed.

Law: 45 CFR 302.56(c)(3)

In nearby states

Your next steps in Washington

  1. Read your current order

    Find the date and the amount on the order.

  2. Compare with the rule

    In Washington: You can ask to change support at any time if circumstances have substantially changed (quitting a job or cutting hours on purpose is not enough by itself).

  3. Show the change

    Papers that show the change make the request stronger.

  4. Send your request

    Request a review from Division of Child Support (DCS), Washington State Department of Social and Health Services (1-800-442-KIDS (5437)) · Apply online

  5. Talk to legal aid

    Ask for free help: WashingtonLawHelp.org (legal aid network).

Where to get free help in Washington

Questions about changing support in Washington

How often can I ask for a change in Washington?

You can ask to change support at any time if circumstances have substantially changed (quitting a job or cutting hours on purpose is not enough by itself). After 1 year, you can ask without a substantial change if the order causes severe economic hardship or a child needs support past 18 to finish high school. After 24 months since the order or last change, you can ask for an adjustment based on changes in either parent's income or in the economic table. DCS can seek a change if the order is at least 15% above or below the standard calculation.

How do I ask to change child support in Washington?

If you have a DCS case, ask DCS to review your order (administrative orders through DCS; court orders through the county prosecutor's office). Or file in superior court: Petition to Modify Child Support (FL Modify 501) for a substantial change, or Motion to Adjust Child Support Order (FL Modify 521) for the 24-month adjustment.

More for Washington

Sources

Sources

Last checked: Oct 25, 2026.

Federal sources