Oregon calculates child support using the Income Shares Model under ORS 25.275, combining both parents' gross incomes to determine a total obligation from a standardized schedule. The state's official child support calculator Oregon tool, maintained by the Oregon Department of Justice, produces a court-ready worksheet that judges rely on in approximately 90% of cases. Oregon sets a minimum child support obligation of $100 per month per child, applies parenting time credits when a parent exceeds 88 overnights per year (24% threshold), and allows deviations under ORS 25.280 for extraordinary circumstances. Administrative rules OAR 137-050-0700 through OAR 137-050-0765 govern the detailed calculations, and updates effective January 1, 2026 (DOJ 9-2025) reflect the latest guideline revisions.
Key Facts: Oregon Child Support at a Glance
| Factor | Detail |
|---|---|
| Calculation Model | Income Shares Model (ORS 25.275) |
| Official Calculator | Oregon DOJ Guidelines Calculator |
| Minimum Support | $100/month per child |
| Parenting Time Credit | Applies at 24%+ overnights (approx. 88 nights/year) |
| Modification Threshold | Change greater than 15% or $50, whichever is less |
| Termination Age | 18 years; extends to 21 if child attends school (ORS 107.108) |
| Filing Fee (Domestic Relations) | $301 (as of March 2026; verify with your local circuit court clerk) |
| Residency Requirement | 6 months continuous if married outside Oregon; none if married in Oregon (ORS 107.075) |
| Governing Rules | OAR 137-050-0700 through 137-050-0765 |
| 2026 Updates | Administrative rule amendments (DOJ 9-2025) effective 01/01/2026 |
How Oregon's Income Shares Model Works
Oregon's child support calculator uses the Income Shares Model, which determines child support by combining both parents' adjusted gross incomes, looking up the total obligation on a standardized schedule based on the number of children, and then splitting that obligation proportionally between the parents based on each parent's percentage of the combined income. This model, codified in ORS 25.275, rests on the economic principle that children should receive the same proportion of parental income they would have enjoyed if the family remained intact. Oregon is one of 41 states using this approach, making it the dominant child support framework in the United States.
The Income Shares Model works in three sequential steps. First, each parent's gross income is determined by adding all income sources including wages, salaries, commissions, bonuses, self-employment income, rental income, investment returns, Social Security benefits, and workers' compensation. Second, the combined adjusted gross income is matched to the state's child support schedule, which produces a base obligation amount for one, two, three, or more children. Third, each parent's share of the total obligation is calculated based on their percentage of the combined income. A parent earning 60% of the combined income is responsible for 60% of the total child support obligation under Oregon law.
Step-by-Step Guide to the Oregon Child Support Calculator
The Oregon Department of Justice provides a free, official child support calculator at justice.oregon.gov/guidelines that generates a court-ready Oregon child support worksheet suitable for filing in family court. The calculator requires approximately 15-20 minutes to complete and produces a printed worksheet that Oregon judges accept as the standard calculation document. Oregon family courts rely on this worksheet in the vast majority of contested and uncontested child support proceedings.
Step 1: Gather Required Financial Documents
Before using the child support calculator Oregon tool, collect the following documents for both parents:
- Last 3 months of pay stubs showing gross income, taxes, and deductions
- Most recent federal and state tax returns (2025 filing year)
- Documentation of self-employment income, including 1099 forms and profit/loss statements
- Records of any additional income: rental properties, investments, Social Security benefits, workers' compensation, or unemployment insurance
- Monthly health insurance premium amounts for the children
- Monthly work-related or education-related childcare costs
- Documentation of any existing child support or spousal support orders from other cases
Step 2: Enter Gross Income for Both Parents
Oregon defines gross income broadly under OAR 137-050-0710. Enter each parent's total monthly gross income from all sources. Oregon courts impute income to voluntarily unemployed or underemployed parents based on their earning capacity, work history, education, and local job market conditions. If a parent is working part-time without justification, the court may calculate child support based on what that parent could earn working full-time at minimum wage or at their demonstrated earning capacity, whichever is higher.
Step 3: Account for Adjustments and Deductions
Oregon allows specific deductions from gross income before calculating support. These adjustments include union dues, mandatory pension contributions, Social Security and Medicare taxes (FICA), existing court-ordered child support for other children, and spousal support paid to the other parent. Health insurance premiums for the children and work-related childcare costs are factored separately into the calculation and divided proportionally between the parents based on their income percentages under Oregon's guidelines.
Step 4: Enter Parenting Time Overnights
The child support calculator Oregon tool requires the number of annual overnights each parent exercises. Under OAR 137-050-0730, a parenting time credit applies when the non-custodial parent has the children for more than 24% of annual overnights, which equals approximately 88 nights per year. This credit reduces the non-custodial parent's obligation proportionally because that parent directly bears child-rearing expenses (food, utilities, housing, activities) during overnight parenting time. A parent with 40% of overnights (146 nights) receives a substantially larger credit than one at the 25% threshold (91 nights).
Step 5: Review the Generated Worksheet
After entering all required data, the calculator produces an Oregon Child Support Worksheet showing each parent's gross income, adjustments, combined income, the basic support obligation from the schedule, each parent's proportional share, parenting time credits, health insurance and childcare allocations, and the final monthly child support amount. Print this worksheet for your records and for filing with the court. Oregon judges are required to use the guideline amount unless specific deviation factors under ORS 25.280 justify a different amount.
Parenting Time Credits Explained
Oregon grants a parenting time credit to the non-custodial parent when that parent exercises more than 24% of annual overnights (approximately 88 nights per year) under OAR 137-050-0730. This credit directly reduces the child support obligation because Oregon recognizes that the non-custodial parent incurs direct expenses (housing, food, transportation, utilities) during overnight parenting time. The credit calculation is proportional: more overnights result in a larger reduction in child support.
The parenting time credit uses the following framework under Oregon's administrative rules:
| Parenting Time Percentage | Approximate Annual Overnights | Credit Impact |
|---|---|---|
| Below 24% | Fewer than 88 nights | No credit applied |
| 24% to 30% | 88 to 110 nights | Modest reduction in support |
| 30% to 40% | 110 to 146 nights | Moderate reduction in support |
| 40% to 50% | 146 to 183 nights | Substantial reduction; approaching equal custody |
| 50% (equal) | 182-183 nights | Each parent's obligation offset; higher earner pays difference |
Oregon courts count only overnight stays, not daytime-only visitation, when calculating parenting time credits. A parent who picks up a child after school and returns the child before bedtime does not receive credit for that day. Weekend visitation of every other weekend (52 overnights per year, or roughly 14%) falls below the 24% threshold and does not trigger any parenting time credit under Oregon law.
Health Insurance and Childcare Costs
Oregon splits the cost of children's health insurance premiums and work-related childcare expenses between both parents in proportion to their respective incomes under ORS 25.275 and OAR 137-050-0740. If Parent A earns 65% of the combined income and Parent B earns 35%, Parent A is responsible for 65% of the children's health insurance and childcare costs. These expenses are added to the base child support obligation and allocated accordingly on the Oregon child support worksheet.
Health insurance costs included in the calculation cover only the incremental cost of adding the children to a parent's plan, not the parent's individual coverage premium. Oregon courts require the parent who can obtain health insurance at the lowest cost to carry the children on their plan. Childcare costs must be work-related or education-related to qualify for inclusion. Voluntary childcare, such as a babysitter used for social activities, does not count toward the child support calculation. Typical monthly childcare costs in Oregon range from $800 to $1,500 per child depending on the child's age, the type of care (daycare center versus in-home provider), and geographic location within the state.
When Oregon Courts Deviate from the Guidelines
Oregon courts may deviate from the guideline amount calculated by the child support calculator Oregon tool when applying the standard formula would be unjust or inappropriate under ORS 25.280. Deviation requires a written finding by the judge explaining why the guideline amount is inadequate or excessive. Common deviation factors recognized by Oregon courts include extraordinary medical expenses for the child, special educational needs or tutoring costs, travel expenses for long-distance parenting time, a child's independent income or assets, the financial resources and needs of each parent, and the standard of living the child would have enjoyed if the family remained intact.
Oregon courts also consider a parent's incarceration, disability, or military deployment as potential grounds for deviation or temporary modification. A parent who voluntarily reduces income (quitting a job, taking a lower-paying position without legitimate reason) does not receive the benefit of a lower calculation. Oregon courts routinely impute income to voluntarily underemployed parents at their demonstrated earning capacity. The burden of proof for a deviation falls on the parent requesting the deviation, and Oregon appellate courts have held that deviations must be supported by specific factual findings, not general assertions.
Modifying an Existing Child Support Order in Oregon
Oregon allows modification of child support orders when there has been a substantial change in circumstances under OAR 137-055-3430. A change is considered substantial when the difference between the current order and a recalculated amount under current guidelines exceeds $50 or 15% of the guideline amount, whichever is less. Parents may request a review and modification through the Oregon Child Support Program if the order is at least 35 months old, or at any time if they can demonstrate a qualifying change in circumstances.
Common grounds for modification in Oregon include:
- A significant increase or decrease in either parent's income (job loss, promotion, career change)
- Changes in the number of children covered by the order
- Changes in parenting time arrangements (more or fewer overnights)
- Changes in health insurance costs or availability
- Changes in childcare expenses
- A child reaching age 18 or 21 (if attending school)
- Incarceration or release of the obligor parent
- A change in either parent's health or disability status
The Oregon Department of Justice Child Support Program conducts administrative reviews, which can result in modified orders without requiring a full court hearing. Either parent may also file a motion to modify directly with the circuit court. The administrative review process typically takes 60-90 days from the date of request. Oregon law requires that at least 60 days have passed since the existing order was entered before a modification request based on changed circumstances can be processed.
When Child Support Ends in Oregon
Oregon child support obligations terminate when the child reaches age 18, unless the child is attending school at least half-time, in which case support continues until age 21 under ORS 107.108. A "child attending school" under Oregon law is a child who is unmarried, between ages 18 and 21, making satisfactory academic progress, and enrolled in school at least part-time. The definition includes college, university, community college, trade school, and vocational programs. Child support also terminates if the child marries, enters active military service, is legally emancipated by court order, or the child dies.
Oregon does not automatically extend child support to age 21. The custodial parent or the child must affirmatively request continuation of support through the Oregon Child Support Program or by filing a motion with the circuit court. The requesting party must provide proof of school enrollment and satisfactory academic progress. If the child drops below half-time enrollment or fails to maintain satisfactory progress, the obligor parent may petition to terminate the extended support obligation. Oregon courts review these requests on a case-by-case basis, considering the child's academic record, the reason for any enrollment gaps, and the financial circumstances of both parents.
Enforcement of Child Support Orders in Oregon
The Oregon Department of Justice Child Support Program enforces child support orders through multiple mechanisms when a parent falls behind on payments. Oregon reports all support arrearages exceeding $150 to the three major credit bureaus (Equifax, Experian, TransUnion), which can significantly damage the delinquent parent's credit score. Oregon intercepts federal and state tax refunds, lottery winnings, and insurance settlements to satisfy overdue child support. The state can suspend or revoke the delinquent parent's driver's license, professional licenses, and recreational licenses (hunting, fishing) under ORS 25.750 through ORS 25.785.
Oregon also employs income withholding orders, which require the obligor's employer to deduct child support directly from wages before the employee receives their paycheck. Federal law limits wage garnishment for child support to 50% of disposable income if the obligor is supporting another family, or 60% if not supporting another family. An additional 5% may be garnished if arrearages exceed 12 weeks. For cases involving severe delinquency, Oregon courts may hold the obligor in contempt of court, which carries penalties of up to 6 months in jail and fines up to $500 per violation.
Filing Fees and Court Costs
Oregon circuit courts charge a filing fee of $301 to commence a domestic relations proceeding, which includes divorce, legal separation, and child support establishment cases. As of March 2026, verify this amount with your local circuit court clerk, as fees may be adjusted periodically. Oregon offers fee waivers for low-income filers whose household income falls at or below 125% of the federal poverty guidelines. For 2026, the federal poverty level for a household of one is approximately $15,650, meaning a single individual earning less than $19,563 per year ($15,650 times 125%) may qualify for a full fee waiver.
Additional costs beyond the filing fee may include service of process fees ($50-$75 for personal service by a sheriff or process server), parenting education class fees ($30-$100 per parent, required in most Oregon counties), mediation fees for contested custody and parenting time disputes, and attorney fees ranging from $200 to $400 per hour for Oregon family law attorneys. An uncontested child support matter handled without an attorney typically costs $350-$500 total including filing fees and service costs.
Frequently Asked Questions
What income does Oregon include when calculating child support?
Oregon includes all gross income from any source under OAR 137-050-0710, including wages, salaries, commissions, bonuses, self-employment income, rental income, investment returns, Social Security benefits, workers' compensation, unemployment insurance, and military pay. Only court-ordered support payments for other children and mandatory retirement contributions are deducted before calculation.
What is the minimum child support payment in Oregon?
Oregon sets a minimum child support obligation of $100 per month per child under the state guidelines, even when the Income Shares Model formula under ORS 25.275 would produce a lower amount. This floor applies regardless of the obligor parent's income level and ensures every child receives a baseline level of financial support.
How does parenting time affect child support in Oregon?
Oregon applies a parenting time credit when the non-custodial parent exercises more than 24% of annual overnights (approximately 88 nights per year) under OAR 137-050-0730. The credit reduces the non-custodial parent's support obligation proportionally. Standard every-other-weekend visitation (52 overnights, roughly 14%) does not trigger the credit.
Can I use the Oregon child support calculator without an attorney?
Yes, the Oregon Department of Justice provides a free, official child support calculator at justice.oregon.gov/guidelines that any parent can use without an attorney. The calculator generates a court-ready worksheet that Oregon judges accept as the standard calculation document. Approximately 85% of Oregon child support cases use the guideline worksheet without attorney involvement.
How often can child support be modified in Oregon?
Oregon permits modification requests when the existing order is at least 35 months old under OAR 137-055-3420, or at any time upon proof of a substantial change in circumstances. A substantial change means the recalculated amount differs from the current order by more than $50 or 15%, whichever is less. At least 60 days must have passed since the current order was entered.
Does child support continue past age 18 in Oregon?
Oregon extends child support to age 21 if the child is unmarried, attending school at least half-time, and making satisfactory academic progress under ORS 107.108. The custodial parent or child must affirmatively request the extension and provide proof of enrollment. Support terminates at age 21 regardless of enrollment status.
What happens if a parent does not pay child support in Oregon?
Oregon enforces child support through income withholding, tax refund interception, credit bureau reporting for arrearages exceeding $150, and license suspension under ORS 25.750. Courts may hold delinquent parents in contempt, carrying penalties of up to 6 months in jail and $500 in fines per violation. Federal law allows wage garnishment of up to 50-65% of disposable income.
How does Oregon handle self-employment income for child support?
Oregon calculates self-employment income using gross receipts minus ordinary and necessary business expenses under OAR 137-050-0715. Depreciation and other non-cash deductions may be added back to income. Oregon courts scrutinize self-employment claims closely and may impute income if the court finds the parent is underreporting. Tax returns, bank statements, and 1099 forms serve as primary evidence.
What is the difference between the Oregon child support calculator and a child support estimator?
The official Oregon child support calculator at justice.oregon.gov/guidelines produces a court-ready worksheet based on the actual state guidelines under ORS 25.275 and OAR 137-050-0710. Third-party child support estimators provide approximate figures but do not generate court-accepted worksheets. Oregon courts require the official worksheet format for all child support proceedings.
Can Oregon child support cover college expenses?
Oregon does not require parents to pay for college tuition as part of child support. However, child support payments continue until age 21 if the child attends school at least half-time under ORS 107.108. Parents may voluntarily agree to share college costs as part of a divorce settlement, and Oregon courts will enforce such agreements as contractual obligations separate from the child support order.