How to Calculate Child Support in Washington State


by Chris Torrone



There are several factors that are taken into consideration when trying to calculate child support. Many people think that the decision is based only on the respective incomes of the custodial and non-custodial parent, or that child support is automatically split 50-50 if there is a 50-50 custodial agreement. However, when you calculate child support, it can be much more complex, and we will break down the ways in which child support is calculated along with resources available for making an estimate of the amount of child support you can expect to pay or receive.

Washington State laws assume that the custodial parent spends money directly on the child, while the non-custodial parent is responsible for paying child support directly to the custodial parent. Typically, a parent is considered non-custodial if the child spends less than 50% of their time with them. 

However even parents with a 50-50 custody agreement may have the parent with a significantly higher income paying some child support to a low-income spouse. Some extenuating circumstances may require that both parents be responsible for paying child support, for example in the instance that the child or children are in the custody of a grandparent or other family member.

Where to Calculate Child Support

The Washington State Legislature Website has a Monthly Basic Support Obligation page that can further help you understand how to calculate child support based on combined monthly income. Basic child support is designed to support food, shelter, utilities, and other basic needs that the custodial parent incurs as the primary caregiver. The calculator will give you the total cost of child support based on parent’s income, which is the number that a judge would then use to determine the percentage of the total amount that each parent is responsible for.

When a court makes a decision on child support, they are primarily looking at the income of each parent, the number of children. Income is the gross amount that each parent receives from all sources, including but not limited to salary, wages, bonuses, commissions, pensions, severance, military pay, and inheritance. Even if one parent is unemployed, they will have gross income calculated based on receiving unemployment, social security payments, disability benefits, or workers compensation. Social services such as EBT, WIC, and TANF are not included in gross income.

From there, net income is determined for each parent by deducting state and federal income tax from the gross amount. Some additional deductions may apply, such as retirement, pension, union dues, and business expenses. 

The Washington State Department of Health and Social Services website has a Quick Child Support Estimator based on those factors. This is a good starting point to get a better idea of what your monthly child support obligation can be. Keep in mind this is just an estimate, but it can still be a helpful tool for getting a ballpark number with which to begin your negotiations for child support.

What goes into the calculation?

The fact is that trying to calculate child support in Washington is not only determined by income and the number of children you have. Other factors such as the cost of group health insurance, the cost of daycare, and the amount of alimony paid if any, also affect the final decision. Parents also have to consider and cover the cost for additional child support expenses, including extra-curricular activity costs, special education expenses, dental and vision insurance if not covered by the group health insurance, additional healthcare costs for a medically fragile child, and travel costs associated with visitation. 

Income determination can be further complicated if one parent has an irregular income schedule (such as in the case of freelancing or a 100% commission based job), or has income sources that are difficult to identify (someone working under the table or choosing to work less than they are able in order to minimize the amount of child support they have to pay.)

It is also important to remember that while child support generally only extends until the age of 18, parents can pursue financial support for college expenses as long as the request is submitted to the family court before the child turns 18 or graduates from high school. Similarly, if a child has special medical needs that will extend beyond the age of 18, a child support order should address the anticipated length and cost of ongoing medical care or social services until they can live independently. Child support can continue throughout adulthood if it is determined that the child will not ever be able to fully support themselves.

Family that is trying to calculate child support

A judge may also calculate child support based on what is in the best interest of the child or children involved, or make adjustments in child support amounts based on change in income or lifestyle that affect them. A full list of standards for determination of income is available for review here.

It is important to have clear expectations between parents about what is deemed an acceptable additional cost. One parent may pursue counseling for their child to support that child’s well being after the divorce, an expense that the other parent may balk at or outright refuse to contribute to. Situations like these can further complicate child support agreements. It is in the best interest of the child for the parents to try to anticipate and work through some of the additional expenses that can come up and how the parents plan to work together to manage those costs when creating a child support agreement.

The DSHS site has a list of common questions related to complex situations that can affect how you calculate child support, and it is a good resource to review when preparing to meet with an attorney. At the end of the day, calculating child support is complicated and there really isn’t an “average” because every family has a unique situation. There is no formula or online calculator that can tell you exactly what you’ll be expected to pay or receive without legal software. The best thing you can do to protect the interests and wellbeing of your child is to work with an attorney who is experienced in family law and committed to pursuing the best course of action to safeguard the financial future of your children.

At Torrone Law, we are committed to compassionate representation for your family. Schedule a free consultation to find out how we can support your family as you determine next steps in calculating and pursuing child support.

Related Posts

Need Help?

Get In Touch

Related Posts

What Happens When an Ex-Spouse Refuses to Pay Child Support?

What Happens When an Ex-Spouse Refuses to Pay Child Support?

You've been through the divorce process, you've spent countless hours and resources in and out of court to ensure that your child's best interests are protected, and you've come to a legal agreement that will ensure that your child is provided for through child...

The Impact of Not Paying Child Support

The Impact of Not Paying Child Support

There are a variety of reasons a parent could fall behind on child support. Adverse financial circumstances and involuntary unemployment are two common reasons, though some parents simply choose not to pay regardless of their financial situation. There are serious...