Oregon Child Support Guidelines: How Support Is Calculated

In Oregon, child support is not negotiated freely between parents — it is calculated using a formula set out in state law and administrative rules, called the Oregon Child Support Guidelines. The guidelines use an "income shares" model: both parents' incomes are combined, and each parent's share of the support obligation is based on how much of that combined income they earn. The dollar figure the formula produces is presumed to be the correct support amount unless a parent successfully rebuts it in court [ORS 25.275; OAR 137-050-0700 to 137-050-0765; ORS 25.280].

How the Oregon formula works

Oregon's child support guideline rules (OAR 137-050-0700 through 137-050-0765) walk through a series of steps rather than a single flat percentage. In broad terms, the formula:

• Adds together both parents' gross incomes to find a combined income figure, then calculates each parent's percentage share of that total.
• Uses that percentage to divide a "basic" support obligation between the parents in proportion to what each one earns.
• Adjusts the result for parenting time, work-related childcare costs, and the cost of the child's health-care coverage.

The amount that comes out of this calculation is rebuttably presumed to be the correct support amount — meaning a court will generally order that amount unless a parent shows the specific facts of the case justify a different number [ORS 25.280].

What counts as income

Oregon's rules define income broadly for support purposes. It generally includes actual or potential gross income — wages, self-employment earnings, pensions, and investment income — along with most other benefits. Some things are specifically excluded, such as child support received for other children, SNAP benefits, and benefits paid on behalf of a child. If a parent is voluntarily unemployed or underemployed, the court can impute "potential" income to that parent rather than using their actual (lower) earnings [OAR 137-050-0715].

Parenting time matters

The guidelines build in a parenting-time credit calculated on a sliding scale tied to each parent's number of overnights with the child per year. As a reference point, a roughly equal parenting-time schedule works out to about 182.5 overnights per year for each parent. The more overnights a parent has, the more that parent's calculated share of support is adjusted to reflect the costs of caring for the child during that time [OAR 137-050-0730].

Childcare and health coverage get added in

On top of the basic obligation, the formula adds in work-related childcare expenses. It also adds the cost of the child's health-care coverage — that cost is treated as reasonable as long as it doesn't exceed 4% of the parents' combined income [OAR 137-050-0735; OAR 137-050-0750].

The self-support reserve — a time-sensitive figure

Oregon protects a paying parent's basic living expenses through a "self-support reserve," which is based on the federal poverty guideline multiplied by 1.167 and adjusted annually. The figure effective July 1, 2025 is approximately $1,522 per month — but because this number is recalculated every year, you should confirm the current figure with the Oregon Department of Justice Child Support Program before relying on it for any calculation [OAR 137-050-0745, eff. July 1, 2025].

Is there a minimum support amount?

Yes — Oregon applies a rebuttable presumption that a parent who owes support can pay at least $100 per month. This presumption has exceptions, including situations involving equal parenting time, income that consists only of disability benefits, incarceration, or reliance on public assistance [OAR 137-050-0755].

Changing or reviewing a support order in Oregon

Two different paths exist once a support order is in place, and they aren't the same thing:

• Periodic review: Once a support order has been in effect for at least 35 months, either parent can request a review of the amount — this right exists regardless of whether circumstances have actually changed [OAR 137-055-3420].
• Court modification: A parent can also ask a court to set aside, alter, or modify a support judgment through a motion, with notice served on the other party (and notice to Oregon's Division of Child Support when required) [ORS 107.135(3)(a)].

These proceedings often arise in the context of a dissolution of marriage. Oregon is a no-fault state — "irreconcilable differences" is a recognized ground for dissolution or separation, so fault generally isn't part of how the case, or the support that comes out of it, is decided [ORS 107.025].

Enforcement and interstate issues

Child support in Oregon connects to a federal enforcement framework. Federal law conditions state funding on states running an enforcement agency and adopting standardized tools such as income withholding, license suspension, and liens (42 U.S.C. §§ 654, 659, 666). It also allows federal wages and benefits to be garnished for support obligations (42 U.S.C. § 659). Separately, once a valid child support order exists, federal law requires other states to enforce it and restricts when a different state can modify it — this is the backbone that coordinates with Oregon's adoption of interstate family support rules when parents live in different states (28 U.S.C. § 1738B).

If support isn't paid, don't expect a bankruptcy filing to erase the debt. Child support and alimony are treated as "domestic support obligations" that cannot be discharged in bankruptcy and are paid ahead of most other unsecured debts. Property-settlement debts owed to an ex-spouse under a divorce decree are also generally non-dischargeable in a Chapter 7 case (11 U.S.C. §§ 507, 523).

What you can do in Oregon

1. Gather income documentation for both parents — pay stubs, tax returns, self-employment records — since the formula runs on combined gross income, not just the paying parent's income [OAR 137-050-0715].
2. Nail down the actual parenting-time schedule in overnights per year, since this directly changes the calculated support amount through the parenting-time credit [OAR 137-050-0730].
3. Add up childcare and health-insurance costs tied to the child so they can be factored into the total obligation [OAR 137-050-0735; OAR 137-050-0750].
4. Confirm the current self-support reserve figure with the Oregon DOJ Child Support Program rather than relying on last year's number, since it's adjusted annually [OAR 137-050-0745].
5. If your order is at least 35 months old, you can request a periodic review even without a change in circumstances [OAR 137-055-3420].
6. If you want to change the order itself, file a motion to modify, with proper notice to the other parent (and to the Division of Child Support when required) [ORS 107.135(3)(a)].
7. If a parent has moved to another state, contact Oregon's Child Support Program about interstate enforcement — only one state's order generally controls at a time (28 U.S.C. § 1738B).
8. If payments are missed, know that enforcement tools like income withholding, license suspension, and liens are backed by federal law, and that past-due support generally cannot be discharged in bankruptcy (11 U.S.C. §§ 507, 523).

This is general information, not legal advice — confirm current figures and how they apply to your situation with the Oregon DOJ Child Support Program or a licensed Oregon attorney.