How is child support set?

Read this in: Spanish / Español

An explanation of Washington State’s child support laws and how child support is set. We go over key parts of the state Child Support Schedule. #3816EN

Please Note:

  • Read this only if you live in Washington State or have children under 18 who live in Washington State and you do not live with their other parent.


A parent has a legal duty to help support their children.

A court’s main concern in setting support is that your children have enough to meet their needs:

  • Clothes
  • Food
  • Decent daycare
  • Medical care, and
  • A place for the children to live (rent or mortgage and utilities).

You will learn:

  • The basics of child support, including who pays it, and
  • How a court decides how much a parent should pay.

You usually must pay monthly.


That parent meets the basic support obligation by having custody of the children.

You and the other parent will fill out Child Support Worksheets. Then the court will use the Washington State Support Schedule to calculate how much support should be in your case.

The court figures out each parent’s income based on the information in your worksheets.

It adds together the parents’ incomes. Then it finds the support amount in the Schedule that applies to the number and ages of your children. This is the “basic support obligation.”

The court can order parents to share the children’s expenses for uninsured medical expenses, premiums, daycare, education, and long-distance transportation.

Usually, you each pay a share using the child support worksheets.

Example: To find out your share of daycare, multiply the total amount of daycare per month by the percentage under your column on line 6 of the child support worksheets.

Orthodontic care, such as braces, and some psychological care (such as special classes or activities the children go to for help with an emotional problem) may not fall into this category. Put these expenses in your child support order instead.

Example: You add a paragraph to the order saying, “The paying parent will pay ___% of the child’s orthodontic care directly to the orthodontist.”

Yes. The support you pay all your biological children should be no more than 45% of your net income.

Each child is entitled to a proportional share. This applies only to the children in the case before the court.

The court can ignore this limit. It can look at if this limit would leave the custodial parent enough to meet the children’s basic needs, and if there are any limits on your earning capacity that are out of your control, such as if you have a disability, an incapacity, or incarcerated. You can read the law about this at RCW 26.19.065(1).

How the court looks at your income

It is your total income before deductions for income tax, FICA, or other expenses.

The Schedule instructions say what to include in your gross income on the child support worksheets.

  • Some overtime income or income from a second job may not count if it is to provide for current family needs or to pay off past relationship or child support debts. You must prove you will stop working overtime or the second job after paying off your debts. You can read the law about this at RCW 26.19.071(4)(i).

The Schedule bases your child support obligation on your net income. That is income after you deduct (subtract) what you pay for taxes and other expenses required by law.

You can take these deductions on the child support worksheets:

  • Federal income tax
  • Social security and Medicare (on some paystubs as FICA)
  • State industrial insurance (L&I)
  • Mandatory union dues
  • Mandatory pension contributions (in some cases)
  • In some situations, up to $5,000 a year of voluntary pension contributions
  • If you are self-employed, you can deduct normal business expenses and self-employment taxes. You must have proof of business expenses.

You can read all allowed deductions at RCW 26.19.071(5).

  • You cannot deduct other amounts taken from your paycheck (Examples: Medical insurance, uniforms, parking) from your income on the child support worksheet.

No and yes.

No, because when filling out the child support worksheets, you put just your income and the other parent’s income.

Yes, because the court looks at your entire situation when deciding support.

You must disclose any household income from:

  • Your new live-in partner or spouse.
  • Other adults and children in your household.

The court also considers the expense of:

  • Children in your household
  • Other children your spouse or partner supports

* If you ask the court to set child support differently (deviate) from the schedule, it will count your spouse or partner’s income.

Generally, you must give the court at least the last 2 years of your federal tax returns and your current pay stubs.

A court that has no information about your income may impute income to you. It decides on an income for you and uses that to set support. You can read more about imputing income in the next section.

Usually, you should give as much proof as you can about your income, earning ability, and financial situation. If you do not, or you voluntarily stop working full time, the court may impute more income to you than you actually make.

  • If you did not file a federal tax return, or your employer does not give pay stubs, you must explain why you do not have these things and give the court other proof of your income. Examples: W2 or 1099 forms, bank statements, or a declaration from your employer.

Imputing Income

It uses this information in this order:

  • Full-time earnings at your current rate of pay.
  • Full-time earnings at your past average rate of pay.
  • Full-time earnings at a part rate of pay where information is incomplete or irregular.
  • Full-time earnings at minimum wage in the area where you live, in certain situations.

A court that has none of this information will use the median income for someone your age and gender. The Child Support Schedule has a median income table.

Yes, if it believes you are voluntarily unemployed or underemployed.

If you are not working or getting public assistance, usually the court will assume you could be working full time. You must prove otherwise.

Yes, if you cannot work due to disability.

Get declarations from your doctor, psychologist, therapist, or other professional explaining why you cannot work and how long you will be unable to work.

Proof that you get SSI, SSDI, or other disability benefit is strong evidence.

Yes, if:

  • You cannot prove you have tried to get work.

Examples: Job search records from the unemployment office; letters turning you down for jobs.

  • You are in school. You must prove you cannot really work until you finish school.

Examples: A school program through WorkFirst, finishing your high school degree, taking English as a Second Language (ESL).

  • You stay home to care for children. There may be exceptions.

Example: One of your children has special needs requiring more care.

Maybe, if:

  • You are working part-time, fewer than 35-40 hours per week. The court will usually multiply your part-time income as if you were full-time.

* The court should not impute income if you cannot work full time because you are following a court-ordered plan (a reunification plan) to get your children back from foster care or CPS. You can read the law about this at RCW 26.19.071(6).

  • You earn less than you used to. You are working full time now. Someone can prove you are earning less on purpose to lower your child support. You can read the law about this at RCW 26.19.071(6).
  • If you earn less for other reasons, such as changing careers, or you are not earning the most someone in your field could, the court should base support on your actual income.

If you are unable to pay the suggested schedule amount

The court might set support lower in special circumstances. This would be a deviation.

If paying the basic support obligation would leave you with income below the federal poverty guidelines, the court should set support lower. Visit ASPE to learn about the federal poverty guidelines.


  • The court might order you to pay $50 per month per child, no matter what this does to your net income. It can set support even lower if you prove you having to pay $50 per child would be unjust. The court must consider how much the children need the $50 per child and how much it would burden you to pay it.
  • You are in prison and have no other assets. Or you are not in prison, but your only income is SSI. In either of these cases, the court can set child support at $0.

When there is good reason to.

The court must:

  • Consider all income and financial resources of all adults in each household.
  • Look at your needs and how lowering support would affect the child’s household.

The Child Support Schedule describes situations where the court can grant a deviation:

  • You support other children. You must prove the children either live with you or you must and do pay support for other children. The court looks at your spouse or partner’s income, any child support or benefits the other children get, and both households’ total circumstances.
  • You split custody or have lots of visitation. The children are not on public assistance. You have much more than every other weekend and a mid-week visit. You must prove how much more you spend on the children when you are together, and any savings to the other parent.
  • You are not likely to make as much in the future. You must include income that is not guaranteed (Examples: Bonuses and overtime) in your gross income when they calculate your payment. Get declarations from your employer or others showing the income will not be available.
  • One parent is very wealthy.
  • One parent pays costs for court-ordered services to reunify with the children.
  • A child has a disability or special needs not covered by insurance. The parent needing these expenses must provide doctors’ letters, medical bills, and receipts.

* You must list any special circumstances in the worksheets.

No, if:

  • It would mean the custodial parent’s household has much less money.
  • The custodial parent would not have enough to meet the children’s basic needs.

Potential issues


You have a legal duty to help support stepchildren until your divorce from the child’s parent is final or the court orders otherwise.

You can read the law about this at RCW 26.16.205.

If you do not have enough money to meet the children’s needs, the court looks at your ability to pay.

TANF, food stamps, ABD and SSI do not count as income in calculating child support.  You list public assistance at line 22f of the child support worksheets. You can ask the court to set the support you must pay at $0.

Most parents who get TANF must take part in WorkFirst.

If you do not have to, ask your DSHS caseworker for a declaration explaining why they are not making you work. See How to Write a Declaration in a Family Law Case.

If you are also working in a correctional industry work program, at least 15% of your gross wages goes to child support. (This is not true if you are in a Class I work program.) You can read the law about this at RCW 72.09.111(1).

The court can also base your child support obligation on any other money, assets, or property you own while in jail/prison. You can read the law about this at RCW 72.09.480.

The court may order post-secondary support in one of these situations:

  • For college or vocational school.
  • The child will still be dependent on the parents after high school graduation.

Example: The child has a disability.

The court must consider (RCW 26.19.090(2)):

  • The child’s age and needs
  • The parents’ expectations for their children when they were together
  • The child's prospects, desires, aptitudes, abilities, or disabilities
  • What the post-secondary education is
  • The parents' level of education, standard of living, and current and future resources
  • How much support the child would have gotten had the parents stayed together

Most support orders do not provide post-secondary support.

If this is true for you, and you think your child will need post-secondary support, you must file a petition asking for it before regular child support payments would end under your order.

Read Getting Child Support after High School to learn more, and/or try to talk with a lawyer. If you have a low income, call CLEAR at 1-888-201-1014.

You each must pay your share of the “basic support obligation” to whoever has custody. This includes the state if the children are getting public assistance or are in foster care.

Download | Printer-friendly

Get Legal Help

Visit Northwest Justice Project to find out how to get legal help. 

Last Review and Update: Oct 27, 2022
Was this information helpful?
Back to top