In Washington State, child support calculation is determined by the income shares model, a standard child support formula. It ensures that children receive the same proportional share of parental income they would have if the family unit remained intact. The process begins with calculating each parent’s monthly gross income and then their monthly net income.
These numbers help find a combined monthly net income. Then, they check this income with the economic table in the Washington State Support Schedule. This shows the total monthly basic support needed. This total support amount is then divided between the parents based on their proportional share of the combined income.
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Torrone’s Takeaways
- Child support calculation is governed by the income-shares model in Washington.
- Monthly net income is the basis for calculation, determined by subtracting allowed deductions such as federal income tax from gross income.
- The Child Support Schedule worksheet is a required legal document for establishing a support amount.
- The economic table is used to determine the monthly basic support obligation based on combined income.
- A parent who is voluntarily underemployed may have an imputed income assigned to them.
- The Department of Social and Health Services can help with the establishment and enforcement of a support order.
- A deviation from the support formula may be granted for reasons such as significant residential time with the child.
- Payments typically end at age 18 or high school graduation, but postsecondary education support can be ordered.
- A modification of support may be necessary if a parent experiences a substantial change in circumstances.

How Washington State Calculates Basic Support
Washington’s child support calculation uses the income shares model. This formula is based on the idea that a child should get the same share of parental income as if the parents lived together. The Child Support Schedule guides the process, beginning with the determination of each parent’s monthly net income.
The court then finds the combined monthly net income of both parents, using it to determine a monthly basic support obligation from the state’s economic table. Each parent’s share of that obligation is based on their proportional share of the combined income.
Washington’s Income Shares Model
The income shares model assumes that children should benefit from both parents’ incomes. Instead of a single flat rate, the child support calculation considers each parent’s ability to pay.
The model calculates a total support amount for the children, and then divides that amount between the parents based on their income. A noncustodial parent usually makes direct child support payments to the custodial parent. This fulfills their support obligation.
Official State Child Support Worksheets
Support Worksheets are the official documents used to calculate child support payments. Family law attorneys and parents alike use these forms to input information such as monthly gross income, deductions, and the number of children.
Automated child support worksheets can make this process easier. They do the needed calculations automatically. These child support worksheets are a necessary part of the legal proceedings for establishing a support order.
Where to Find the State’s Economic Table
The child support economic table is a fundamental part of the Washington State Support Schedule. It is a table that shows the total monthly basic support obligation based on the parents’ combined monthly net income and the number of children.
The table can be found within the Washington State Court Forms website, often alongside the official child support worksheets and other family law documents.
Table: Washington’s Basic Support Obligation Per Child (Example)
| Combined Monthly Net Income | MONTHLY BASIC SUPPORT OBLIGATION for 1 Child | MONTHLY BASIC SUPPORT OBLIGATION for 2 Children |
|---|---|---|
| $2,000 | $433 | $334 |
| $4,000 | $843 | $643 |
| $6,000 | $1,048 | $795 |
| $8,000 | $1,270 | $960 |
| $10,000 | $1,451 | $1,099 |
What Counts as Income for Child Support?
Family law attorneys in Washington State know that the definition of income is quite broad during a child support calculation. Gross income includes:
- Salaries
- Wages
- Bonuses
- Commissions
- Pensions
- Dividends
- Interest
- Retirement benefits like Social Security
The goal of the court is to get a full picture of each parent’s financial standing to determine a fair monthly child support obligation. Parents are required to provide financial documentation, such as tax returns, to support their reported income.
All Income Sources Are Considered
Gross income is the starting point for a support calculation. It is a full list of all the money received. This includes unemployment benefits and income from self-employment. That’s before subtracting self-employment taxes.
The court uses this information to establish each parent’s total financial resources. Deductions for taxes and other mandatory payments are then subtracted to arrive at the monthly net income.
When a Judge Imputes a Parent’s Income
When a parent is voluntarily unemployed or underemployed, a judge may impute income to them. Imputing income means the court sets an income level based on the parent’s work history, education, and earning ability. The court does this instead of using their current lower earnings.
This prevents a parent from deliberately earning less to lower their support amount. The court considers various factors when it imputes income, including the parent’s age, health, and available job opportunities.
Income Not Counted in the Calculation
Some sources of income are not included in the child support calculation. These can include Supplemental Security Income (SSI), public assistance, and other support for children from other relationships.
The income of a new spouse or domestic partner is also typically excluded. Knowing which financial resources are counted and which are not is an important part of completing the Support Worksheets accurately.

Other Expenses That Add Up
Beyond the basic support obligation, child support orders in Washington State can account for additional child-related expenses. These are costs that are not included in the state’s economic table, and they are a major part of a family’s budget.
Courts use child support worksheets to outline how these costs, such as childcare costs and medical expenses, will be shared between parents. The goal is to provide for all of a child’s needs.
Mandatory Add-on Expenses
Some expenses are considered mandatory add-ons to the support amount. These are expenses that are typically shared by the parents in proportion to their monthly net income. One example is work-related day care expenses. Another is the cost of health insurance premiums. These expenses are detailed in the final support order to support your partner and your children and must be paid as directed.
Discretionary Expenses
Other expenses are considered discretionary, which means a judge has some leeway in whether to include them. These are special expenses for a child. They include costs for extracurricular activities. They also include private school tuition or certain educational expenses.
A court may order parents to share these costs, especially if they were part of the family’s spending patterns before the parents separated. These costs often relate to special needs or specific interests of the child.
Health Insurance and Medical Costs
Health care costs are a significant consideration in any child support order. The cost of a child’s health insurance premium is typically shared between parents based on their proportional share of the combined monthly net income.
Uninsured medical costs like co-pays, deductibles, and other out-of-pocket expenses are usually split in the same way. These costs include orthodontic care and psychological care. Parents must also make arrangements for how these reimbursements will be handled.
How to Handle High and Low Income Situations
Washington State has provisions to handle child support calculations in cases where one or both parents have particularly high or low incomes. The law ensures that the support amount is fair and doesn’t create undue hardship for either parent.
This is achieved through adjustments to the standard support formula. These changes help parents keep enough money for their own basic needs. They also make sure parents meet their financial and legal duties to their children.
The High Income Cap
The Washington child support calculator and the child support economic table are accurate for families with a combined monthly net income up to a certain limit. If the parents’ combined income exceeds this amount, the court may set a higher child support amount based on written findings of fact.
A parent’s support obligation owed for all of their children will generally not exceed 45% of their net income, except for good reason. This allows the court to determine an appropriate support set that reflects the family’s higher standard of living.
Self Support Reserve
The state protects a low-income parent from an unfair financial burden with the self-support reserve. This is an amount equal to 125% of the federal poverty guideline for a one-person family.
A court will not usually reduce a parent’s net income below this reserve when it sets a monthly child support obligation. The exception is the minimum payment. This provision aims to ensure that the parent responsible for paying child support has enough income to meet their own basic living expenses.
The $50 Per Child Minimum Support Amount
In situations where a parent’s income is very low, there is a minimum support amount. The law generally mandates a minimum of $50 per child per month, regardless of the parent’s income. A court may order a lesser amount only if it would be “unjust” to apply the minimum. This minimum payment makes sure every child gets some financial help from their parents. This applies even when income is very limited.

When the Standard Calculation Is Not Fair
Sometimes, using the standard support formula causes one parent to have too much financial burden. It can also fail to meet the child’s needs properly. The state’s child support schedule allows for a “deviation” from the standard child support calculation in these specific circumstances. The judge must make written findings of fact to explain the reason for the deviation.
Cases Deserving a Valid Deviation
A court may grant a deviation for several reasons. One common reason is a residential schedule. The parent who pays child support spends a lot of time living with the child. This increases their child-rearing costs.
Other reasons could be a parent’s legal duties to children from other relationships. They could also be extraordinary debts not voluntarily incurred. Or a child’s special needs that require extra medical or educational expenses. A judge will consider the total financial picture of both households.
When a Deviation Is Not Allowed
A deviation is not a guarantee and can be denied. A court may not deviate if doing so would result in insufficient funds in the household receiving the child support payments to meet the child’s basic needs.
A deviation is also generally not permitted if the child receives public assistance. The income of a new spouse or domestic partner alone is not enough to change the support amount. However, it may be considered with other factors.
Common Reasons for Requesting a Change
When a parent’s circumstances change, they can file a petition to modify the child support order. Common reasons for a child support change include a major change in either parent’s income. Another reason is a change in the parenting plan or where the child lives. A big change in the child’s needs, like new healthcare or education costs, is also a reason.
Table: Checklist for a Child Support Calculation
| Document Type | Description |
|---|---|
| Tax returns | Complete personal tax returns for the last two years, including all schedules. |
| Pay stubs and W-2s | Most recent pay stubs for at least six months and W-2s from the last two years for all jobs. |
| Financial statements | Bank statements, investment account statements, and any other records of income. |
| Spousal maintenance | Any court-ordered maintenance or support received from a prior marriage. |
| Child-related expenses | Documentation of childcare costs, special needs expenses, and any other extraordinary costs. |
| Healthcare expenses | Proof of health, dental, and vision insurance premiums, as well as a record of any uninsured medical expenses. |
When Do Child Support Payments Stop?
The termination of child support payments is a significant milestone for parents. In Washington, the end of a support obligation is not always clear-cut.
Standard Termination Age
A child support order in Washington state typically ends when the child turns 18 years old or graduates from high school, whichever occurs later. The support amount will not continue past the child’s 19th birthday if they have not yet graduated from high school. Certain events can end a support order before the child turns 18. These include the child getting married, becoming legally independent, or joining the military.
When a Child Stays in High School
If a child turns 18 while they are still a full-time high school student, the support payments continue until they graduate. This provision recognizes the financial dependency of a child still in school.
A court may order the paying parent to continue providing support until the end of the school year. However, a parent cannot be ordered to pay child support for a child who has turned 19 and has not yet graduated high school.
Post-Secondary Education Support for College
Parents may be ordered to provide post-secondary support for their children who continue their education after high school. This is not an automatic extension of the original support order; one of the parents must petition the court for it.
The court decides the amount and length of post-secondary support. It looks at the child’s needs, their school performance, and the money both parents have. This type of support generally ends when the child turns 23.
Modifying an Existing Child Support Order
Life circumstances are not static, and a support order established years ago may no longer be fair or meet a child’s needs. Washington state law lets parents change child support when big changes happen.
These changes must be legally recognized and proven to the court, as minor or temporary fluctuations do not typically justify a change. Family law attorneys can help determine if a modification is appropriate and guide you through the process.
Legal Grounds for Changing an Order
A parent can request a modification by demonstrating a “substantial change in circumstances.” This could be a big change in either parent’s monthly net income. It could also be a change to the parenting plan or residential schedule. Or it could be a change in the child’s needs, like new healthcare expenses.
If more than 24 months have passed since the last order, a parent can ask for a change without proving a major change. But the parent must show there was a change in income or other factors. These changes would lead to a new support calculation. A change must be at least 15% to be considered.
Modification Process
To begin a child support modification, a parent must file a petition to modify the child support order with the superior court. They must also complete new child support worksheets. They must fill out a financial declaration with up-to-date information on their gross income and expenses.
These documents must then be officially served to the other parent. The process is complex. Many parents get help from family law attorneys or the Division of Child Support. They want to make sure all forms are filled out correctly and filed on time.
What to Expect During the Review
Once the petition is filed, the court will review the new information to determine if an adjustment is warranted. The other parent has a chance to respond and may submit their own financial documents.
A hearing may be scheduled where both parents present their arguments to the court. The court will use the new financial data to run a fresh child support calculation, ultimately issuing an updated support order with a new support amount.
Frequently Asked Questions
1. How does a parent’s imputed income impact the child support calculation?
If a parent is voluntarily underemployed, the family court may assign an income amount to them based on their earning capacity. This imputed income is then used to determine a fair support amount.
2. Can a parent who pays spousal maintenance receive credit toward child support?
Yes, if you are paying court-ordered maintenance, a portion of that amount may be deducted from your gross income. This will lower your overall monthly net income for child support calculation purposes.
3. What does it mean to receive child support?
A parent who receives child support is designated to get child support payments from the other parent. The funds are meant to help take home pay cover a child’s living expenses.
4. When can I file a Motion to Adjust Child Support Order?
A motion to adjust a child support order can be filed when a parent has a modification of support reason. A substantial change in circumstances or a 15% change in income can be a reason.
5. How do overnight visits affect the child support schedule?
In Washington, significant overnight visits can be a reason for a deviation from the standard child support schedule. This adjustment recognizes the higher child-rearing costs incurred by the paying parent.
6. Do I need a lawyer to receive child support?
While you can file paperwork on your own, a family lawyer is often beneficial. A Washington child support lawyer can help you complete the Child Support Schedule worksheet and navigate child custody proceedings.
7. Can I request postsecondary education for my child?
A parent must petition the court for postsecondary education support for college expenses. This is not an automatic extension of a child support order, but rather a separate request.
Conclusion
Washington State’s approach to child support calculation provides a framework for creating fair and enforceable child support orders. By working with family law attorneys or the Department of Social and Health Services, you can ensure that your financial declarations are accurate. If you take an active part in family court, you can set a support amount that fits your family’s needs.






