The standard calculation is the presumptive monthly child support amount determined by following the Washington child support schedule exactly. Courts must use this amount unless specific written reasons for deviation are provided under RCW 26.19.035.
RCW 26.19.011: Standard calculation means the presumptive amount of child support owed as determined from the child support schedule before the court considers any reasons for deviation. Courts must state this amount in every child support order under RCW 26.19.035(4).
The standard calculation is the result of completing Lines 1 through 17 of the WSCSS worksheet in order:
Lines 1-4: Income calculation
Line 5: Basic obligation from economic table
Line 6: Proportional income shares
Lines 7-9: Basic obligation after SSR limitations
Lines 10-13: Healthcare and daycare expenses
Line 14: Each parent's expense share
Line 15: Gross child support obligation
Lines 16: Credits for direct payments
Line 17: Standard Calculation = Line 15 - Line 16d
Every Washington child support order must state the standard calculation even if the court orders a different amount due to deviation. The standard calculation is the baseline the court compares all deviations against. If no deviation is granted the standard calculation is the transfer payment.
Not always. If the court approves a deviation the transfer payment will differ from the standard calculation. But the order must always state both amounts — the standard calculation and the actual ordered amount.
Only with court approval. An agreement alone without written findings from the court is not a valid deviation.
It can be reviewed any time either parent experiences a substantial change in circumstances of 15% or more change in net income under RCW 26.09.170.
Use our 2026 Washington State estimator to see how these legal terms impact your support amount. All calculators are RCW 26.19 compliant.