Oregon Child Support — Calculator, Laws & Guide (2026)

Understanding Oregon child support laws helps both custodial and non-custodial parents know their rights and obligations. This comprehensive Oregon child support guide covers how payments are calculated, what income counts, when support can be modified, and how orders are enforced. Whether you are going through a divorce, seeking a modification, or dealing with non-payment, this guide explains Oregon’s child support system in plain language.

Verified against Oregon statutes and federal OCSE guidelines as of May 2026.

Oregon Child Support Overview

Oregon uses the income shares model for calculating child support. This model is based on the principle that children should receive the same proportion of parental income they would have received if the family were intact. Both parents’ incomes are combined, and the support obligation is divided proportionally.

Oregon uses the Income Shares Model under ORS 25.275 and OAR 137-050-0700 through 137-050-0765. Both parents’ gross incomes are combined to determine a basic support obligation from an Obligation Scale based on the number of children. Each parent’s share is proportional to their percentage of combined income. The formula adjusts for parenting time (overnights), health insurance costs, and childcare costs. The guidelines presume the calculated amount is correct under ORS 25.280 but allow rebuttal.

How Oregon Calculates Child Support

The Oregon child support calculation considers multiple factors:

1. Determine each parent’s gross income — wages, salary, commissions, bonuses, self-employment income, investment income, and other sources.
2. Calculate combined parental income — add both parents’ adjusted gross incomes together.
3. Apply the guideline schedule — Oregon’s guidelines provide a base support amount based on combined income and number of children.
4. Prorate between parents — each parent’s share is proportional to their percentage of the combined income.
5. Add healthcare and childcare costs — these are added to the base amount and divided proportionally.
6. Apply adjustments — parenting time credits, other child obligations, and special circumstances may adjust the final amount.

Online calculator: Use our child support estimator below to calculate your estimated obligation.

What Counts as Income in Oregon

Gross income before taxes and deductions per OAR 137-050-0715. Includes wages, salaries, commissions, bonuses, self-employment income, rental income, investment income, Social Security benefits, workers compensation, and employee benefits that reduce living expenses (company car, housing). Excludes income of new partners or spouses for purposes of calculating the presumptive amount. The rule defines income as the actual or potential gross income of a parent.

Imputed income: YES. If a parent is voluntarily unemployed or underemployed without good cause, Oregon courts impute income based on earning capacity. Factors considered include work history, qualifications, education, health, and local job market conditions. A parent cannot avoid support obligations by refusing to work or taking a lower-paying job without legitimate reason. Courts may impute at least full-time minimum wage or demonstrated earning capacity, whichever is higher.

Deviation factors: Under ORS 25.280, the presumptive guideline amount may be rebutted if unjust or inappropriate. Criteria include: other available resources of the parent; net income remaining after legally required withholdings; special hardships (medical circumstances, extraordinary travel costs for parenting time, reunification plan requirements); desirability of custodial parent remaining home full-time; tax consequences to both parents; financial advantage from a spouse or domestic partner’s household income. Factors already built into the formula cannot be used as a basis for rebuttal. Income disparity between parties and joint legal custody alone are not valid rebuttal grounds.

Healthcare & Childcare in Oregon Child Support

Health insurance: Health insurance is a mandatory component of child support orders. The cost of private health care coverage is considered reasonable if it does not exceed 4 percent of the parents’ combined gross income. Either parent can be ordered to provide coverage. If neither parent has insurance available, the court can order cash medical support. Compelling factors (such as a child’s chronic health condition) may justify ordering coverage at a cost exceeding the 4 percent threshold. The non-providing parent contributes through an adjustment to the support obligation. Medical support is governed by OAR 137-050-0750.

Childcare costs: Work-related childcare costs are included in the child support calculation. Costs are split proportionate to each parent’s share of combined income. If one parent pays all childcare, the child support amount is adjusted so both parents effectively contribute to the cost. The guidelines calculator factors childcare into the overall support obligation.

When Does Oregon Child Support End?

In Oregon, child support generally ends when the child reaches 18, but may continue to age 21 if the child is unmarried and attending school at least half-time under ORS 107.108. The child must be making satisfactory academic progress as defined by the school. Continuation is not automatic — the custodial parent or child must affirmatively request it through the Oregon Child Support Program or circuit court. School includes college, university, community college, trade school, and vocational programs.. However, support may continue or end earlier based on:

• The child graduates from high school (if still a minor)
• The child becomes emancipated (marriage, military service, self-supporting)
• The child has special needs requiring ongoing support
• College support: YES, but only as continued child support (not a separate college contribution order). Under ORS 107.108, if a child aged 18–20 is unmarried, enrolled at least half-time in school (including college, community college, trade school, or vocational program), and making satisfactory academic progress, child support can continue until age 21. Oregon does not have a separate statute requiring parents to pay tuition or college expenses directly — support is paid as ongoing child support to the custodial parent or child attending school.

Modifying Oregon Child Support

When to modify: A substantial change in circumstances exists when the difference between the existing order amount and the recalculated guideline amount exceeds 50 dollars or 15 percent of the guideline amount, whichever is less, per OAR 137-055-3430. Alternatively, modification may be requested if at least 36 months have passed since the order was entered or last modified. At least 60 days must have elapsed since the current order was entered before any modification request.

How to modify: Modification can be done administratively through the Oregon Child Support Program (administered by the Oregon Department of Justice) or judicially through the circuit court. For administrative review, a parent contacts the Oregon Child Support Program to request a review and adjustment. For judicial modification, a parent files a motion to modify with the circuit court. Either parent can initiate. The process typically takes 90 to 120 days. Oregon courts also accept stipulated modifications where both parents agree to changes.

Either parent can request a modification. Changes are typically not retroactive to before the date of filing the modification request.

Oregon Child Support Enforcement

Oregon has multiple tools to enforce child support orders when a parent fails to pay:

• Income withholding (wage garnishment — effective the same day the order is received
• withheld starting next pay period); state and federal tax refund intercepts; license suspension (driver’s
• occupational
• recreational
• and business licenses when arrears exceed 2500); contempt of court (fines and/or jail for willful nonpayment); credit bureau reporting; passport denial (when arrears exceed 2500
• through federal OCSE); property liens; interception of other federal payments; judgment debtor examinations

Contact Oregon Child Support Program, administered by the Oregon Department of Justice, Division of Child Support at https://www.doj.state.or.us/child-support/ for enforcement assistance.

Additional Oregon rules: Oregon uses a Parenting Time Credit — the formula adjusts support based on the number of overnights each parent has, calculated through the official Parenting Time Calculator. The 4 percent combined income cap on health insurance costs is a distinctive Oregon threshold (with exceptions for compelling factors). Oregon’s 36-month automatic review eligibility (no need to prove changed circumstances) is a notable feature. The license suspension threshold is 2500 in arrears. Oregon’s Child Attending School provision (ORS 107.108) extending support to age 21 for students is more generous than many states. Administrative and judicial modification tracks operate in parallel, giving parents a choice of process.

Official Sources & Resources

• Oregon Child Support Program, administered by the Oregon Department of Justice, Division of Child Support: https://www.doj.state.or.us/child-support/
• Federal OCSE: acf.hhs.gov/css
• Cornell LII — Child Support: law.cornell.edu
• Oregon Guidelines Statute: ORS 25.270 through 25.280 (statutory authority); OAR 137-050-0700 through 137-050-0765 (administrative rules implementing the guidelines and Obligation Scale). Key provisions: ORS 25.275 (formula and criteria), ORS 25.280 (presumption and rebuttal), OAR 137-050-0710 (calculating support), OAR 137-050-0715 (income definition), OAR 137-050-0750 (medical support), OAR 137-050-0760 (rebuttals). College-age support: ORS 107.108. UIFSA: ORS Chapter 110.

Last verified May 2026. Contact us if you notice outdated information.

Estimate Your Child Support

Use our free child support estimator to calculate estimated monthly payments. Enter both parents’ incomes, number of children, and custody arrangement to see a personalized breakdown based on your state’s formula.

Related Guides

• Oregon Divorce Process Guide
• Oregon Child Custody Guide
• Oregon Alimony Guide
• All Child Support Guides