Washington Child Support Calculator (2026)

How Washington calculates child support

Washington uses the income-shares model under chapter 26.19 RCW. The court adds the parents’ monthly net incomes, uses the economic table in RCW 26.19.020 to find the basic support amount for each child, adds those amounts, and divides the total between the parents in proportion to their net incomes. The result is the standard calculation; the court can deviate from it only with written findings.

The table was replaced effective January 1, 2026, by 2025 legislation implementing the child support schedule work group’s recommendations. The new table extends to $50,000 of combined monthly net income, starts at $2,200, and lists amounts per child by family size. The older table stopped at $12,000 and used age brackets; neither feature survives in the 2026 version.

This page covers the standard calculation for one to five children. It does not reproduce the AOC worksheets, which also handle healthcare, daycare, special expenses, credits, and deviations.

The 2026 economic table

The table runs from $2,200 to $50,000 of combined monthly net income in $100 steps, with a column for each family size from one to five children. Each cell is the monthly amount per child. For two children at $8,000 of combined income the cell is $960, so the basic obligation is $1,920.

The worksheet instructions say to round the combined income to the nearest $100: round down when the last two digits are 49 or less, and up when they are 50 or more. This calculator applies that rule before reading the table. There is no interpolation between rows.

Above $50,000 of combined net income the table is no longer presumptive; the court may exceed it on written findings. The calculator uses the $50,000 row, so a high-income estimate here is a floor.

Net income and the deductions Washington allows

The worksheet starts with gross monthly income from all sources: wages, overtime and bonuses that are not excluded, self-employment and business income, interest and dividends, maintenance received, and other income such as unemployment, disability, Social Security, pensions, and capital gains. Income of a new spouse or other household adult, child support received, gifts and prizes, and means-tested benefits are excluded.

The deductions are listed in RCW 26.19.071(5): federal and state income taxes actually owed, FICA and self-employment taxes, mandatory pension plan payments, mandatory union or professional dues, mandatory state deductions such as the paid family and medical leave program, long-term services and supports, and industrial insurance premiums, court-ordered maintenance actually paid, up to $5,000 a year of voluntary retirement contributions with a pattern of contributions, and normal business expenses for self-employed parents.

A court can impute income to a parent who is voluntarily unemployed or underemployed, using current or historical earnings, minimum wage, or median income tables. A calculator that takes one net figure per parent cannot reproduce that analysis.

The self-support reserve and the $50 minimum

The low-income rules sit in RCW 26.19.065 and in lines 8 and 9 of the worksheet. The self-support reserve is 180% of the federal poverty guideline for a one-person family, which was $2,394 a month as of January 13, 2026.

A parent whose net income is below the reserve pays the presumptive minimum of $50 per child. A parent above the reserve has the basic obligation capped at income minus the reserve, and the result is never below $50 per child. When combined income is below $2,200, the obligation is $50 per child unless the court finds that unjust.

There is also a separate 45% limit: no parent’s support for all of their children may exceed 45% of net income except for good cause. This calculator does not apply it, because it depends on children outside the order.

Shared time, healthcare, and add-ons

The standard calculation has no timeshare variable. When a child spends a significant amount of time with the parent who pays support, the court may deviate under RCW 26.19.075(1)(d) by weighing the increased costs in that household against the reduced costs in the other. That is a discretionary deviation, not a formula, and this estimate does not include it.

Healthcare and daycare are not in the economic table. Health insurance premiums, uninsured medical costs, daycare, education expenses, and long-distance transportation are shared in the same proportion as the basic obligation. They are added on the worksheet and can change the total substantially.

A Washington example at $8,000 combined

Parent A earns $5,000 and Parent B earns $3,000 of monthly net income, with two children. Combined income is $8,000, and the two-child column gives $960 per child, or $1,920 for both. Parent A’s 62.5% share is $1,200 a month.

The self-support reserve matters at lower incomes. With Parent A at $3,000 and Parent B at $3,200 and two children, the standard calculation would be $778, but Parent A’s income above the reserve is $606 ($3,000 − $2,394), so the obligation is $606. At the bottom, $1,500 and $500 with two children gives $100, the $50 per-child minimum.

When the official worksheets are the better choice

The AOC worksheets and the DSHS calculator handle the full calculation: the per-child table, line 8 limits, healthcare and daycare, credits, and deviations. Use them if the parents share significant time with the child, if either parent has children outside the order, or if a parent’s income must be imputed.

A Washington family law attorney is the right next step when the parents disagree about income or the residential schedule. The standard calculation is the starting point; the court’s order controls.

Frequently asked questions