Parents in Washington are increasingly choosing 50/50 parenting plans. A common belief is that if you share equal residential time, neither parent will pay child support.
That belief is usually wrong.
Washington’s child support laws focus on your child’s needs and each parent’s ability to pay, not on “who has the kids more nights.” Even when residential time is split 50/50, the court typically:
- Calculates a standard child support amount;
- Decides who is the obligor (payer) and who is the obligee (recipient); and
- Only then considers whether to deviate based on the residential schedule and other factors.
Understanding how this works can help you set realistic expectations before you negotiate a parenting plan or walk into court.
How Washington Calculates Child Support
Washington’s child support system is governed primarily by chapter 26.19 RCW (the child support schedule) and chapter 26.18 RCW (enforcement).
Legislative policy
The Legislature has said the purpose of the child support schedule is to “[ensure] that child support orders are adequate to meet a child’s basic needs and to provide additional child support commensurate with the parents’ income, resources, and standard of living. The legislature also intends that the child support obligation should be equitably apportioned between the parents”. (See RCW 26.19.001.)
Step 1: Basic child support obligation
The court starts by setting the “basic child support obligation” from the economic table based on:
- The parents’ combined monthly net income, and
- The number and ages of the children.
See RCW 26.19.011(1) and RCW 26.19.020.
The basic child support obligation is a figure that is meant to represent the total cost of raising the children each month, without considering who will be paying who yet. The formula for calculating the basic support obligation is provided by the state and rooted in economic data of how much kids cost, on average, to raise.
Step 2: Standard calculation
Next, the court allocates that basic obligation between the parents in proportion to their incomes. This yields the standard calculation, defined as:
“the presumptive amount of child support owed as determined from the child support schedule before the court considers any deviation.” – RCW 26.19.011(8)
In State ex rel. M.M.G. v. Graham, 159 Wn.2d 623 (2007), the Washington Supreme Court considered parents who shared equal residential time. The father argued for a special “shared custody” formula. The fathers argument was rooted in a prior holding of the court. Previously, the court allowed for such a formula in a scenario where each parent had one of the two children all of the time (split custody arrangement). The court declined to apply a similar formula to joint custody, holding:
- The court must still use the standard calculation under chapter 26.19 RCW for shared custody, and
- Any inequities arising from the shared schedule should be addressed through deviations, not a separate formula.
- The court held that a “specific formula is not necessary or statutorily required to ensure the parents’ child support obligation is properly allocated”
Step 3: Who pays who?
The parent owing this amount is the obligor; the other is the obligee. The support actually paid is the “support transfer payment”.
- Obligor as “the person owing a duty of support”
- Obligee as the custodian to whom that duty is owed.
See RCW 26.18.020(12)–(13).
But who is the Obligor and who is the Obligee? Washington state statutes do not explicitly say. However, in discussing the legislature’s intention for the child support statutes, House Bill 1478 provides that
‘One parent, who is the “noncustodial parent” or the “non-primary residential parent,” is usually required to make a “support transfer payment” or a child support payment to the “custodial parent” or “primary residential parent.”’ (HB 1478).
Judges rule in line with this common sense understanding of the statute. If the kids are spending the majority of their time with one parent, that parent will be the one incurring most of the everyday expenses and made the “obligee” or receiver of child support. Even if the obligee has significantly higher income than the obligor, the obligor will still be required to pay the obligee their proportionate share of the basic support obligation.
The legislature does not provide any special formula for determining the obligor and obligee when the residential schedule is 50/50. In practice, what happens in joint custody scenarios almost universally is that the parent with the higher income is made the obligor. Judges reason that if the kids are spending equal time with both parents, the transfer payment will continue to be made such that the financial resources available to support the children will be similar in both households.
One example of this comes from the unpublished opinion In the Matter of the Marriage of: Matthew Flax v. Hao Ding. The court held that “the designation of obligor/obligee is not contingent on residential placement; when parents share residential time one parent may be designated obligor based on a higher income”. This reasoning by the appellate court is consistent with my practice experience at the county level.
Step 3: Deviations – including for the residential schedule
This is where the ‘obligor’ with significant residential time can seek relief. Only after the standard calculation is set does the court consider deviations. Reasons to deviate from the standard calculation listed in RCW 26.19.075 include:
- Other children to support,
- Extraordinary income/expenses, and
- The residential schedule.
For a residential-schedule deviation, the statute provides:
The court may deviate from the standard calculation if the child spends a significant amount of time with the parent who is obligated to make a support transfer payment, but may not deviate on that basis if:
- It would leave the receiving household with insufficient funds to meet the child’s basic needs, or
- The child is receiving Temporary Assistance for Needy Families (TANF).
Deviations require specific written findings supported by evidence. If the court does not enter those findings, it must order the standard calculation. RCW 26.19.075(2)–(3).
Washington courts repeatedly describe deviations as the exception, not the rule. However, all else being equal, a 50-50 residential schedule is usually grounds to argue for one. In my practice experience, judges are really only likely to order anything in the realm of a $0 transfer payment (no child support) if both parents have roughly the same income or financial backing. If the parents have vastly different incomes, the one with the higher income will usually receive only a small deviation or none at all. Indeed, if the lower income parent is receiving government assistance a deviation is prohibited by statute. Arguing for a deviation is very fact specific and the kind of thing a lawyer will help you build a case for or against by presenting evidence of specific financial circumstances.
What to expect in cases with 50/50 residential schedules
1. Parents with substantially equal incomes
If both parents earn roughly the same amount the court may grant a residential-schedule deviation, sometimes bringing the transfer payment down to a low amount, and in some cases, close to or at zero. However, Washington courts emphasize that zero support is not automatic in equal-time cases; it remains a deviation that must be justified in written findings.
2. Parents with significantly different incomes
Where there is a meaningful income gap, even with a 50/50 schedule:
- The higher-income parent almost always remains the obligor under the standard calculation.
- The court can deviate downward to account for the fact that the child spends equal time in each home, but it must not reduce support so much that the lower-income parent’s household cannot meet the child’s basic needs.
In State ex rel. M.M.G. v. Graham, for example, the court approved a significant downward deviation in favor of the higher-income parent, from $872.33 to $300, because the children spent half their time with him and the deviation did not leave the other parent without sufficient funds to meet the children’s needs.
In practice, these cases are heavily fact specific and run the gamut from no deviation to a $0 transfer payment.
3. When one parent is on TANF or other public assistance
If the child or receiving household is on Temporary Assistance for Needy Families (TANF):
- RCW 26.19.075(1)(d) expressly prohibits a residential-schedule deviation if it would result in insufficient funds in the receiving household or if the child is receiving TANF.
- In practice, that often means the court will not reduce support based on 50/50 time in a way that undermines the family’s ability to meet basic needs.
- Some or all support may be assigned to the State as reimbursement for public assistance, so DSHS has a direct interest in keeping the support order at an adequate level.
Talk to a Washington Child Support Attorney About Your Specific Case
The way a 50/50 parenting plan impacts child support depends heavily on:
- The exact income (and imputed income) of each parent,
- The actual residential schedule,
- Whether anyone is receiving public assistance, and
- Other deviation factors such as children from other relationships or extraordinary expenses.
If you’re in Jefferson, Island, Kitsap, Clallam, or San Juan County and considering a 50/50 parenting plan – or already have one and want to understand how it should affect child support – an experienced Washington family law attorney can walk through the worksheets, explain realistic outcomes, and advocate for a fair arrangement.
I represent parents in Port Townsend, Whidbey Island (Oak Harbor and Coupleville), Sequim, Port Angeles, Silverdale, Bremerton, Bainbridge Island, Poulsbo, Port Orchard, and surrounding areas. Call or text me at 1-360-643-0113 to schedule a free consultation and discuss the specifics of your case.
