Washington lawChild SupportMarriageVisitationDaubert Standard

How to Modify Child Support in Washington

September 21, 2026 · LawDiver Research Team

Substantially changed circumstances at any time (§ (5)(a)); severe economic hardship of either party after one year (§ (7)); and — after 24 months — adjustment without any showing of changed circumstances based on income changes or changes in the economic table (§ (9)). A child reaching age 12 or changing age group may also warrant adjustment. That is what separates Washington modifying child support from a generic national summary. Read RCW 26.09.170(5), (7), (9) before the background sections below. File a petition/motion to adjust filed in superior court, or a DCS administrative process. Only installments accruing after the petition may be modified (§ 26.09.170(1)(a)); arrears are protected. DCS may seek administrative modification of IV-D orders.

What counts as a change in Washington

Facts that most often support modification:

Income changes. Job loss, demotion, retirement, disability, or a significant raise on either side. Voluntary quits and deliberate underemployment usually backfire — courts may impute income.
Parenting-time shifts. A new custody order, a child moving households, or substantial unexercised visitation.
The child's needs. New medical or educational expenses, health-insurance changes, or a child reaching an age that changes the guideline bracket.
Guideline updates. In many states, a recalculated guideline amount that differs from the current order by the statutory margin is itself the change — RCW 26.09.170(5), (7), (9) controls how that math works here.
Incarceration, military deployment, or other statutory events that Washington treats as qualifying changes.

Facts that rarely work: a short gap between jobs, a new partner's income (usually not imputed to a parent), lifestyle choices, or the passage of time alone where Washington still requires a showing.

Step-by-step: how to file

A petition/motion to adjust filed in superior court, or a DCS administrative process. The typical sequence:

Confirm jurisdiction. Washington courts modify their own orders; if the child and parties have moved, the Uniform Interstate Family Support Act (UIFSA) determines which state may act. Generally the issuing state keeps exclusive continuing jurisdiction until all parties and the child have left, or the parties agree in writing to transfer.
Gather financial proof. Two to three years of tax returns, recent pay stubs, proof of benefits or disability, health-insurance costs, and child-care invoices. Expect a financial affidavit or worksheet under RCW 26.09.170(5), (7), (9).
File the modification request. A petition/motion to adjust filed in superior court, or a DCS administrative process.
Serve the other parent. Service starts the retroactivity clock in most states — delays cost you.
Exchange discovery. Interrogatories, document requests, and sometimes a vocational evaluation if underemployment is disputed.
Negotiate or litigate. Many modification cases settle at mediation or a case-management conference; a stipulated modification must still be approved and entered by the court.
Get the new order entered. Support does not change until a judge signs — keep paying the existing order until then.

When the change takes effect (retroactivity)

Only installments accruing after the petition may be modified (§ 26.09.170(1)(a)); arrears are protected.

This is the single most expensive mistake in modification practice. If circumstances changed in January but the motion is filed in June, the months in between are almost always governed by the old order. Filing promptly — even before you have perfect evidence — protects the effective date.

A concrete Washington scenario

Here is one way the Washington pieces fit together. Change any fact and the statute may point somewhere else.

A parent in Washington lost income after the last child-support order and wants the number changed.

File in the superior court that entered the decree, or the Division of Child Support (DCS) for Title IV-D cases using a petition/motion to adjust filed in superior court, or a DCS administrative process.
Prove the Washington standard: Substantially changed circumstances at any time (§ (5)(a)); severe economic hardship of either party after one year (§ (7)); and — after 24 months — adjustment without any showing of changed circumstances based on income changes or changes in the economic table (§ (9)). A child reaching age 12 or changing age group may also warrant adjustment.
Expect the effective date to follow this rule: Only installments accruing after the petition may be modified (§ 26.09.170(1)(a)); arrears are protected.
If the case is IV-D, also consider administrative review: DCS may seek administrative modification of IV-D orders.

A Washington modification is a new order under RCW 26.09.170(5), (7), (9). It is not automatic, and arrears already due generally stay due.

Periodic reviews and administrative modification

DCS may seek administrative modification of IV-D orders.

Administrative review is often faster and cheaper than litigation, but its scope is narrower: agencies adjust amounts under the guidelines, while only the superior court that entered the decree, or the Division of Child Support (DCS) for Title IV-D cases can resolve disputed facts about custody, income imputation, or deviations.

Interstate cases (UIFSA)

When parents live in different states, a Washington order can usually be registered and enforced anywhere, but modification follows UIFSA's jurisdictional rules. Register the order in the responding state, then seek modification where the law permits it. Do not simply stop paying while a jurisdictional fight is pending — arrears keep accruing under the existing order.

Case law: how Washington courts decide modification motions

The opinions below are in the LawDiver corpus, with block quotes pulled from the opinion text so you can jump straight into the full decisions.

In Re Marriage of Dodd

In Re Marriage of Dodd, 86 P.3d 801 (2004)

…. David Dodd appeals a Spokane Superior Court child support modification order entered in favor of Karen Dodd based upon income imputed to Mr. Dodd under RCW 26.19.071(6). The issue is whether the trial court properly revised its court commissioner's order, which also imputed income to Mr. Dodd, but at a lower amount based upon what the commissioner believed Mr. Dodd could earn…

Practitioners open In Re Marriage of Dodd when Washington child support modification turns on the distinction in this sentence: "David Dodd appeals a Spokane Superior Court child support modification order entered in favor of Karen Dodd based upon income imputed to Mr. Dodd under RCW 26.19.071(6)." Do not lift it out of the facts the court was deciding.

In Re Marriage of Scanlon and Witrak

In Re Marriage of Scanlon and Witrak, 34 P.3d 877 (2001)

…878 879 *880 BAKER, J. Barry Scanlon appeals an order on modification of child support that increased his child support obligation, allocated long distance transportation expenses and tax exemptions, and ordered postsecondary educational support, but failed to address his request for attorney fees. We reverse. I Barry Scanlon and Bonnie Witrak, both physicians, dissolved the…

Washington opinions such as In Re Marriage of Scanlon and Witrak are cited where child support modification is disputed. The court stated: "R, J. Barry Scanlon appeals an order on modification of child support that increased his child support obligation, allocated long distance transportation expenses and tax exemptions, and ordered postsecondary educational support, but failed to address his request for attorney fees." That is the language to brief; the rest of the decision supplies the procedural posture.

In Re Marriage of Shoemaker

In Re Marriage of Shoemaker, 904 P.2d 1150 (1995)

…ated a child support order entered 5 years previously which modified the terms of the original dissolution decree. Under the vacated order, each parent had custody of one child and neither was obligated to pay child support. The effect of the court's decision was to reinstate the child support obligation contained in the original decree requiring the father to pay support. Judg…

Practitioners open In Re Marriage of Shoemaker when Washington child support modification turns on the distinction in this sentence: "Under the vacated order, each parent had custody of one child and neither was obligated to pay child support. The effect of the court's decision was to reinstate the child support obligation contained in the original decree requiring the father to pay support." Do not lift it out of the facts the court was deciding.

In Re Marriage of McLean

In Re Marriage of McLean, 937 P.2d 602 (1997)

…due process are satisfied when pleadings in a proceeding to modify an award of child support under a dissolution decree entered by a Washington court are served upon the nonpetitioning parent by certified mail, return receipt requested, but the mailing is returned marked unclaimed. We hold such service satisfies the statute and due process, and therefore affirm the Court of App…

In Re Marriage of McLean is worth reading on Washington child support modification because the court put the point in its own words: "Washington court are served upon the nonpetitioning parent by certified mail, return receipt requested, but the mailing is returned marked unclaimed." Use that passage as the starting point, then read the facts that precede it.

In Re Marriage of Daubert

In Re Marriage of Daubert, 99 P.3d 401 (2004)

…nt. APPELWICK, J. Richard Johnson appeals the trial court's modification of his child support payments on three grounds. First, the trial court failed to enter separate findings of fact and conclusions of law to support the increased support amount. Second, the "scant findings" in the Order of Child Support are not supported by the evidence. Finally, the court's decision was ba…

In Re Marriage of Daubert is worth reading on Washington child support modification because the court put the point in its own words: "APPELWICK, J. Richard Johnson appeals the trial court's modification of his child support payments on three grounds. First, the trial court failed to enter separate findings of fact and conclusions of law to support the increased support amount." Use that passage as the starting point, then read the facts that precede it.

In Re Marriage of Didier

In Re Marriage of Didier, 140 P.3d 607 (2006)

…oward the amount above, the court may entertain a motion to modify this Order. CP at 118. Michael appealed and the trial court stayed its contempt order pending this appeal. ¶ 7 We answer two questions: (1) Is the order requiring Michael to pay $942 in child support enforceable? (2) Is the order on contempt criminal (punitive) or civil (remedial)? ¶ 8 If the order is remedial,…

Washington opinions such as In Re Marriage of Didier are cited where child support modification is disputed. The court stated: "Order. CP at 118. Michael appealed and the trial court stayed its contempt order pending this appeal. ¶ 7 We answer two questions: (1) Is the order requiring Michael to pay $942 in child support enforceable?" That is the language to brief; the rest of the decision supplies the procedural posture.

In Re Marriage Holmes

In Re Marriage Holmes, 117 P.3d 370 (2005)

…eparate trial court decisions entering a parenting plan and modifying child support. A provision in the parenting plan granting the guardian ad litem (GAL) authority to determine when to reinstate the original return time in the residential schedule was a proper temporary order and not a modification of the parenting plan. In addition, because the child now resides with the fat…

Practitioners open In Re Marriage Holmes when Washington child support modification turns on the distinction in this sentence: "A provision in the parenting plan granting the guardian ad litem (GAL) authority to determine when to reinstate the original return time in the residential schedule was a proper temporary order and not a modification of the parenting plan." Do not lift it out of the facts the court was deciding.

In Re Marriage of Dicus

In Re Marriage of Dicus, 40 P.3d 1185 (2002)

…ies, without final action, filed various motions to vacate, modify or clarify the decree relative to the federal benefits and Mr. Dicus's required transfer payment for child support. The parties' correspondence included a proposal by Mr. Dicus's former attorney for child support of $500 per month, $250 of which would come from Mr. Dicus's social security benefits. Later, Mr. Di…

In Re Marriage of Dicus is worth reading on Washington child support modification because the court put the point in its own words: "Mr. Dicus's required transfer payment for child support. The parties' correspondence included a proposal by Mr. Dicus's former attorney for child support of $500 per month, $250 of which would come from Mr. Dicus's social security benefits. Later, Mr." Use that passage as the starting point, then read the facts that precede it.

Practical checklist before you file

Re-read the existing order: does it recite a modification standard, a reservation of jurisdiction, or agreed deviation findings? Those terms shape your burden.
Run the current Washington guideline calculation on today's incomes before filing; know the percentage gap.
Assemble documents that date the change (termination letter, disability award, new lease, custody order).
Calendar the three-year review cycle if Washington offers one for your case type.
Keep paying the current order until a new one is entered — arrears are nearly impossible to erase later.
Search LawDiver for recent Washington modification decisions before briefing or mediating.

Key takeaways

Washington modification actions are filed in the superior court that entered the decree, or the Division of Child Support (DCS) for Title IV-D cases.
The legal standard: Substantially changed circumstances at any time (§ (5)(a)); severe economic hardship of either party after one year (§ (7)); and — after 24 months — adjustment without any showing of changed circumstances based on income changes or changes in the economic table (§ (9)).
Only installments accruing after the petition may be modified (§ 26.09.170(1)(a)); arrears are protected.
DCS may seek administrative modification of IV-D orders.
A modification is never automatic — even when a percentage threshold is met, the court must enter a new order.
Companion reading: Washington child support guidelines and how to modify spousal maintenance in Washington.

The legal standard in Washington

In practice, the moving parent carries the burden. The court compares the facts as they stood when the last order was entered against the facts today, and asks whether the difference is significant enough — and durable enough — to justify a new order. Judges distinguish between temporary setbacks (a few weeks of reduced hours) and genuine, continuing changes (a layoff, a new custody schedule, a child's changed medical needs).

Frequently asked questions

Can child support be modified in Washington?

Yes. Substantially changed circumstances at any time (§ (5)(a)); severe economic hardship of either party after one year (§ (7)); and — after 24 months — adjustment without any showing of changed circumstances based on income changes or changes in the economic table (§ (9)). A child reaching age 12 or changing age group may also warrant adjustment. Modifications are handled through a petition/motion to adjust filed in superior court, or a DCS administrative process.

How much does income have to change to modify child support in Washington?

Can Washington child support be modified retroactively?

Only installments accruing after the petition may be modified (§ 26.09.170(1)(a)); arrears are protected. Plan on the current order controlling until a new one is entered.

Who can request a modification?

Either parent, and in IV-D cases the state child support agency on a parent's behalf. DCS may seek administrative modification of IV-D orders.

Do I need a lawyer to modify child support in Washington?

Not always — the superior court that entered the decree, or the Division of Child Support (DCS) for Title IV-D cases accepts filings from self-represented parents, and administrative reviews are designed for that. Contested income imputation, self-employment income, or interstate jurisdiction issues are where counsel matters most.

Does the other parent's refusal to follow the visitation order change support?

Not automatically. Custody interference and support are legally distinct issues in Washington; withholding support in response to withheld visitation typically creates arrears and contempt exposure. Seek modification or enforcement of the parenting order through the court instead.

Disclaimer

This guide is general legal information about modifying child support in Washington, not legal advice. Statutes, guidelines, and case law change. Confirm the current text of RCW 26.09.170(5), (7), (9) and consult a licensed Washington family-law attorney about your specific order.