Quick answer: Washington uses income shares on net income under RCW chapter 26.19. Each parent’s gross income from any source, less income taxes, FICA, mandatory pension and union dues, other mandatory state deductions such as paid family and medical leave premiums, industrial insurance premiums, court-ordered maintenance actually paid and up to $5,000 a year of voluntary retirement contributions, is the monthly net income. The economic table (RCW 26.19.020, in effect since January 1, 2026) gives a basic support obligation per child for combined monthly net income from $2,200 to $50,000 and one to five children; it is multiplied by the number of children and divided between the parents by their share of combined net income. Below $2,200 of combined net income the presumptive support is $50 per child. A parent’s basic obligation cannot reduce his or her net income below the self-support reserve of 180% of the federal poverty guideline ($2,394 a month in 2026), except for the $50 per child minimum, and neither parent’s obligation may exceed 45% of net income without good cause. Health care, day care and special child rearing expenses are not in the table and are shared in the same proportions, with credit for what each parent pays. The standard calculation is presumptive; the residential schedule, other children, nonrecurring income and other reasons can support a deviation with written findings.
How Washington child support works
- Gross to net income. See from gross income to net income.
- The economic table and the self-support reserve. See the economic table and the self-support reserve.
- Health care, day care, credits and deviations. See health care, day care, credits and deviations.
What this calculator checks
The calculator uses the 479 rows of the economic table ($2,200 to $50,000, one to five children) read from RCW 26.19.020, rounds the combined net income to the nearest $100 as the worksheet instructs, applies the limits and credits of the Washington State Child Support Schedule worksheet and was checked against an independent re-implementation. It does not compute the residential schedule deviation, imputed income, children from other relationships or the good-cause exceptions to the 45% limit.
Child support across Washington
The schedule applies in every superior court, from Seattle, Spokane, Tacoma, Vancouver, Bellevue or Everett, and in administrative proceedings of the Division of Child Support. Worksheets in the form developed by the Administrative Office of the Courts must be filed under penalty of perjury.
Frequently asked questions
How is child support calculated in Washington?
Both parents' net incomes are combined, the economic table gives a per-child basic obligation that is multiplied by the number of children, and each parent pays his or her share of combined net income, with limits for low incomes and credits for expenses.
What is the Washington economic table range in 2026?
Combined monthly net income from $2,200 to $50,000 for one to five children; above $50,000 the court may exceed the table amount on written findings.
What is the Washington self-support reserve?
180% of the federal poverty guideline for one person: $2,394 a month for 2026.
What is the minimum child support in Washington?
A presumptive $50 per child per month, unless the paying parent shows it would be unjust.
Does Washington cap child support at 45% of net income?
Neither parent's obligation for all of his or her children may exceed 45% of net income except for good cause.