Washington State Child Support Calculator

Estimate WA child support using the RCW 26.19 Economic Table. Calculates net income, basic support, transfer payment, health insurance and childcare add-ons, and deviation analysis.

Updated April 2026 RCW 26.19 (post-EHB 1014) Private — runs in your browser

NCP Monthly Gross Income

Custodial Parent Monthly Gross

Number of Children

Washington Basic Child Support

$740/mo

Combined Net Income$7,684/mo

Basic Support (WA Table)$1,233/mo

NCP Net Income Share60.0%

Post-EHB 1014 (effective January 1, 2026): RCW 26.19 Economic Table now extends to $50,000/mo combined net income. Self-support reserve raised to 180% of the federal poverty guideline (~$2,347/mo). Low-income protection threshold is $2,200/mo combined net; presumptive minimum is $50 per child.

Advanced Calculator

WA Economic Table by children count, income sensitivity chart, add-on breakdown, and 10-year year-by-year projection with income growth.

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RCW 26.19 Inputs

NCP Monthly Gross

CP Monthly Gross

Children

WA Economic Table Result

$740/mo base

Combined Net Income$7,800/mo

Basic Support (Table)$1,233/mo

NCP Net Income Share60.0%

WA Support by Number of Children (current income)

Children	Table Basic Support	NCP Monthly Obligation	Annual
1	$951/mo	$571/mo	$6,847
2 ← selected	$1,233/mo	$740/mo	$8,878
3	$1,424/mo	$854/mo	$10,253
4	$1,583/mo	$950/mo	$11,398
5	$1,730/mo	$1,038/mo	$12,456

Health Insurance/mo

Work Childcare/mo

Total Transfer Payment: $740/mo base + $132/mo health + $240/mo childcare = $1,112/mo

Professional Simulator

Full RCW 26.19 worksheet with itemized income (W-2, SE, bonuses, rental), detailed net income calculation, all add-ons, retroactive support, what-if scenarios, NPV, and 20-year projection.

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NCP Income — Total: $72,000/yr (Net: $5,230/mo)

W-2 / Salary

Self-Employment

Bonuses

Rental Income

CP Income — Total: $45,000/yr (Net: $3,466/mo)

W-2 / Salary

Self-Employment

Add-Ons & Retroactive

Children

Health Insurance/mo

Work Childcare/mo

Long-Distance Transport/mo

Extraordinary Expenses/mo

Retroactive Months

mos

WA RCW 26.19 Professional Analysis

$1,253/mo

NCP After-Tax

Gross: $72,000/yr

Federal tax: −$7,542

SE tax: −$1,696

After CS: $3,977/mo

Transfer Components

Base support: $880/mo

Health ins.: +$132/mo

Childcare: +$241/mo

Transfer: $1,253/mo

How Washington State Child Support Works in 2026

Washington calculates child support under RCW 26.19 using the Economic Table model. Both parents' net monthly incomes are combined to look up the basic support obligation from the WA Economic Table. Each parent's share is proportional to their net income.

2026 overhaul — EHB 1014, effective January 1, 2026: the RCW 26.19 Economic Table now extends to $50,000/mo combined net income (up from $12,000). The Self-Support Reserve was raised from 125% to 180% of the 1-person federal poverty guideline (~$2,347/mo). The low-income presumptive-minimum threshold was raised from $1,000 to $2,200/mo combined net income. Presumptive minimum support remains $50 per child per month. EHB 1014 also adds PFML and WA Cares (LTSS) premiums as mandatory deductions when calculating net income.

Washington Net Income (Post-EHB 1014)

Washington uses net income: gross income minus federal income taxes, FICA, mandatory union dues, health insurance premiums for the parent (not the children), court-ordered support for other children, normal business expenses for the self-employed, Washington Paid Family and Medical Leave (PFML) premiums, and WA Cares (LTSS) premiums. Washington has no state income tax.

Transfer Payment Calculation

Washington uses the concept of a "transfer payment" — the net amount the non-custodial parent owes to the custodial parent. Basic support from the table is allocated by income share, then add-ons for health insurance, childcare, and extraordinary expenses are added. The parent who pays health insurance may receive a credit.

Deviation from Standard Calculation

Courts may deviate from the standard calculation when factors under RCW 26.19.075 apply, including: non-standard residential time, split custody arrangements, children with special needs, undue economic hardship, or a parent's income that would result in a support order exceeding 45% of their net income.

NCP Net Monthly = Gross − Federal Tax − FICA − Deductions
Combined Net → WA Economic Table → Basic Support
NCP Transfer = Basic Support × (NCP Net ÷ Combined Net)
+ Health Insurance × NCP% + Childcare × NCP% + Extraordinary × NCP%

Worked Example

Dad (NCP): $6,000/mo gross (~$4,680 net). Mom: $4,000/mo gross (~$3,120 net). Two children.

Combined Net Income~$7,800/mo

Basic Support (WA Table)~$1,988/mo

Dad's Net Share60%

Dad's Basic Obligation$1,193/mo

+ Health & Childcare+$372/mo

Total Transfer Payment$1,565/mo

Official Sources & Legal References

Frequently Asked Questions

How does Washington calculate net income for child support? ▼

Washington uses net monthly income: gross income minus federal income taxes (Washington has no state income tax), FICA/Social Security taxes, mandatory union dues, health insurance for the parent personally (not the children), and court-ordered child support for other children. For self-employed parents, reasonable business expenses are deducted first, then taxes. Courts may impute income to voluntarily unemployed or underemployed parents.

What is a deviation from the WA child support schedule? ▼

Under RCW 26.19.075, courts may deviate from the standard economic table amount when certain factors exist. Common deviation grounds include: extraordinary parenting time arrangements, split custody where each parent has some children, a child's special medical or educational needs, a parent's income that would create a hardship, or when standard support would exceed 45% of the obligor's net income. Any deviation must be supported by written findings.

Does Washington have a minimum child support order? ▼

Yes. Washington sets a minimum basic child support obligation of $50 per month per child when income is very low. Even when the calculated amount would be less, courts generally order at least this minimum to keep the obligation active and enforceable. Courts also consider whether the obligor has the actual ability to pay when setting very low orders.

When can Washington child support be modified? ▼

Washington allows modification when there is a substantial change in circumstances. This includes a significant change in either parent's income, a change in the child's residential schedule, changes in childcare or healthcare costs, or when the child turns 18 and support should be reduced. Under RCW 26.09.170, a substantial change that would result in a 25% or greater change in the support amount generally qualifies for modification.

Are college expenses included in Washington child support? ▼

Washington courts have authority under RCW 26.19.090 to order post-secondary education support for children up to age 23 who are enrolled in a qualifying academic program. This is separate from regular child support and is based on the cost of attending an in-state public university. Parents must request post-secondary support before the child turns 18, and the court considers each parent's financial ability and the child's aptitude for higher education.

When to Consult a Washington Family Law Attorney

Consult an attorney if your case involves: the 2026 post-EHB 1014 Economic Table reforms and how they affect your existing order, deviation requests under RCW 26.19.075 (split custody, special needs, hardship), post-secondary education support requests under RCW 26.19.090 before the child turns 18, or modification where the 25% change threshold is disputed.