The Oregon child support calculator is the official tool used to determine how much child support one parent pays to the other, ensuring children receive appropriate financial support from both parents regardless of custody arrangements. Administered by the Oregon Department of Justice and available free online at justice.oregon.gov/guidelines, this calculator implements Oregon's child support guidelines using a standardized formula that accounts for parental incomes, parenting time percentages, health insurance costs, childcare expenses, and other relevant factors. Whether you're going through divorce, establishing paternity, modifying an existing child support order, or simply estimating your potential child support obligation, understanding how to use the Oregon child support calculator accurately ensures fair support amounts that meet your children's needs while reflecting each parent's financial capacity.
Accessing the Oregon Child Support Calculator
The official Oregon child support calculator is available online at no cost, providing parents, attorneys, mediators, and courts with a standardized tool for calculating support obligations.
Official Calculator Location
Navigate to justice.oregon.gov/guidelines to access the Oregon Department of Justice's official child support calculator. This is the same calculator used by the Oregon Child Support Program, family courts, and administrative law judges to determine support amounts, ensuring consistency across all cases.
The calculator is web-based and accessible from any device with internet connection and a modern web browser. No registration, login, or personal information is required to use the calculator for estimation purposes, making it freely available to anyone wanting to understand potential support obligations.
Alternative Calculator Versions
In addition to the web-based calculator, the Oregon Department of Justice provides an Excel spreadsheet version for "power users" including attorneys, mediators, and frequent users who prefer working offline or integrating calculations into other documents. The Excel version implements the identical formula and produces the same results as the web calculator.
Both calculator versions are updated regularly to reflect current Oregon child support guidelines, ensuring accuracy and compliance with applicable administrative rules governing support calculations.
Important Limitations and Disclaimers
The calculator provides estimates based on information entered and assumes that information is accurate and complete. The results are not guarantees of what support will be ordered in actual cases. Several important limitations apply:
Estimation Only: The calculator produces estimated support amounts, not binding determinations. Actual support orders may differ based on evidence presented, special circumstances, or court findings.
Final Authority: Judges, administrative law judges, and child support administrators have final authority to determine appropriate support amounts in actual cases. While they typically follow guideline calculations, they can deviate when circumstances warrant.
Garbage In, Garbage Out: Calculator accuracy depends entirely on the accuracy of information entered. Incorrect income figures, parenting time percentages, or other inputs produce incorrect results.
No Legal Advice: The calculator doesn't provide legal advice or guidance about specific situations. Consider consulting with family law attorneys for personalized advice about your circumstances.
Step-by-Step Guide to Using the Calculator
The Oregon child support calculator walks users through a series of screens collecting information about parents, children, income, parenting time, and expenses. Following the proper sequence and entering accurate information ensures reliable results.
General Information Section
Parent and Child Information: Begin by entering both parents' names and selecting the relationship between them (married, unmarried, or if the child is with a caretaker or in state care). Enter children's names, birth dates, and select which children are included in this particular calculation if parents have multiple children from different relationships.
Relationship Selection: The calculator asks whether parents are married, divorced/never married, or if children are with a third-party caretaker or in state foster care. This selection affects certain aspects of the calculation including how support is allocated when children are in care.
Children Selection: If parents have multiple children together or from other relationships, select which specific children are included in this calculation. Support amounts vary based on the number of children requiring support and whether either parent has support obligations for children from other relationships.
Income Section
Income represents the most critical factor in child support calculations, requiring careful attention to ensure accuracy.
Gross Monthly Income: Enter each parent's gross monthly income—income before any deductions for taxes, retirement contributions, health insurance, or other withholdings. The calculator specifically requires monthly figures, so annual salaries must be divided by 12, while weekly or biweekly income must be converted to monthly equivalents.
Income Sources: Oregon defines income broadly to include virtually all sources of money received including:
- Wages, salaries, commissions, tips, and bonuses
- Self-employment income (gross receipts minus ordinary and necessary business expenses)
- Investment income including dividends, interest, and rental income
- Unemployment compensation and workers' compensation
- Social Security retirement or disability benefits
- Pension and retirement income
- Spousal support received from someone other than the other parent in this case
- Military allowances and benefits
- Any other regular income from any source
Income Documentation: While the calculator accepts whatever figures you enter, actual support proceedings require documentation including paystubs, tax returns, W-2 forms, 1099 forms, profit and loss statements for self-employment, and other proof of income.
Unknown Income: If you don't know the other parent's income when running preliminary estimates, the Oregon Department of Justice suggests using:
- Information from the Oregon Employment Department website showing average wages by occupation and region if you know their occupation
- Full-time minimum wage for the state where they live if you don't know their occupation or income
For 2024, Oregon's minimum wage varies by location: $14.20 per hour in standard counties, $15.45 in large counties, and $13.20 in rural counties. Full-time minimum wage monthly income ranges from approximately $2,288 to $2,678 depending on location.
Imputed Income: When parents are voluntarily unemployed or underemployed without good cause, courts may impute income based on earning capacity rather than actual earnings. The calculator allows entering actual income or potential income based on work history, education, qualifications, health, and job opportunities in the community.
Spousal Support Adjustment: If one parent pays spousal support to the other as part of the divorce, enter the monthly spousal support amount in the designated field. The calculator automatically reduces the payer's income and increases the recipient's income by the spousal support amount, recognizing that money transferred as spousal support shouldn't generate additional child support obligations.
Union Dues: Monthly union dues are deductible from gross income. Enter the monthly union dues amount, and the calculator reduces that parent's income accordingly since union membership is often required for employment.
Parenting Time Section
The amount of time children spend with each parent significantly affects child support calculations through the parenting time credit.
Annual Overnights: Enter the number of overnights each parent expects to have with the children annually. Oregon counts overnights rather than daytime hours, and the calculation looks at a full year (365 nights).
For a 50/50 parenting schedule where children alternate weeks, each parent has 182.5 overnights annually. For every-other-weekend schedules (52 weekends = 104 overnights annually), plus one midweek overnight per week (52 additional nights), the parent with less time has 156 overnights (42.7% of nights).
Parenting Time Calculator: Oregon provides a separate Parenting Time Calculator tool that helps estimate annual overnights based on specific parenting plans. This calculator allows entering detailed schedules including regular weekly patterns, holiday rotations, and summer vacation arrangements, then automatically calculates total annual overnights.
Many parents use calendar tools or custody scheduling software to calculate exact overnights by mapping out their complete parenting plan over a two-year period and counting the actual nights children spend with each parent.
Parenting Time Credit Percentage: The calculator automatically converts annual overnights into a parenting time credit percentage. This percentage doesn't match the actual overnight percentage due to how the guidelines allocate credit.
The parenting time credit recognizes that when one parent has most parenting time, they incur most day-to-day expenses. As parenting time approaches equal, parents share more expenses. However, some costs like housing are duplicated in shared parenting situations.
Consequently, the parenting time credit percentage exceeds the actual overnight percentage when a parent has limited parenting time but is less than the overnight percentage when parents share time more equally.
For example, a parent with 125 annual overnights (34.24% of nights) receives only 23.65% parenting time credit. Meanwhile, a parent with 182.5 annual overnights (50% of nights) receives 50% parenting time credit.
Adult Children Note: Parenting time becomes irrelevant once children turn 18 and graduate high school (or turn 19). Even though support may continue until age 21 for full-time students, the parenting time credit no longer applies, potentially changing support amounts when children transition to adulthood.
Health Insurance Section
Every Oregon child support order must address children's health insurance coverage, making health insurance costs a required component of calculations.
Parent's Own Insurance Cost: Enter the monthly premium cost for each parent's own health insurance coverage (employee-only coverage, not including coverage for children or other family members). This amount is deductible from gross income, similar to union dues, because parents don't pay child support based on money they must spend for their own health insurance.
If you're unsure of the employee-only cost, contact your HR department for a breakdown showing:
- Employee only cost
- Employee plus dependents cost
- Employee plus family cost (if different from dependents)
Children's Insurance Cost: Enter the monthly premium cost specifically to add children to health insurance coverage. Calculate this by subtracting the employee-only cost from the employee-plus-dependents cost.
For example, if employee-only coverage costs $150 and employee-plus-dependents costs $380, the children's insurance cost is $230 ($380 - $150).
Treatment of Children's Insurance: Unlike parents' own insurance which reduces income, children's insurance premiums are allocated proportionally between parents based on their income percentages. If one parent provides health insurance, the child support amount automatically adjusts so both parents contribute proportionally to the premium cost.
Reasonable Cost Standard: The Oregon child support guidelines consider health insurance reasonable in cost if it doesn't exceed 4% of both parents' combined gross incomes. Insurance costing more than 4% may still be ordered if compelling factors exist, such as:
- Children have chronic health conditions requiring frequent medical care
- Parents agree to continue coverage despite the cost
- The cost only slightly exceeds 4%
- No other affordable coverage options exist
Cash Medical Support: If neither parent has access to affordable health insurance for children, the calculator can include cash medical support—additional monthly amounts designated for anticipated medical expenses instead of insurance premiums.
No Insurance Below Minimum Wage: Parents whose income falls below minimum wage cannot be required to pay for or contribute to health insurance costs or cash medical support.
Childcare Expenses Section
Work-related or education-related childcare costs factor into child support calculations.
Monthly Childcare Costs: Enter the average monthly cost of childcare necessary to enable the custodial parent to work or attend job training or education programs. Only childcare expenses directly related to employment or education qualify—childcare for social activities or personal time doesn't count.
Proportional Allocation: Like children's health insurance, childcare costs are allocated proportionally between parents based on their income percentages. The parent actually paying childcare providers has child support automatically adjusted so both parents contribute proportionally.
Fluctuating Costs: Childcare expenses often vary as children age, schedules change, or employment circumstances shift. Some parents prefer to exclude childcare from the official support calculation and instead agree to split actual childcare costs proportionally as incurred. This approach avoids repeatedly modifying support orders every time childcare expenses change.
School-Age Children: As children enter school full-time, childcare needs often decrease substantially or change to after-school care rather than full-day care. Support calculations should reflect current anticipated childcare costs rather than historical expenses.
Additional Children Section
The number of children each parent supports affects child support calculations.
Other Children Count: Enter the number of other children each parent has legal obligations to support, whether through other child support orders or children living in the parent's household. This recognizes that parents supporting multiple children have less available income for any single child support obligation.
Impact on Calculation: Additional children reduce the income available for the child support obligation being calculated, potentially lowering support amounts. However, having other children doesn't automatically eliminate or dramatically reduce support—it's simply one factor in the overall calculation.
Calculation Results
After entering all required information, click the calculate button to generate results showing:
Total Support Obligation: The combined amount both parents should contribute monthly for children's support, based on their combined incomes and number of children.
Each Parent's Share: The amount each parent is responsible for paying based on their proportional income, before parenting time credits and other adjustments.
Parenting Time Credit: The reduction in each parent's obligation based on the number of overnights they have with children.
Adjusted Obligation: Each parent's final support amount after accounting for parenting time credit, health insurance costs, childcare expenses, and other adjustments.
Transfer Payment: The bottom line showing which parent pays support to the other and in what monthly amount. This represents the net transfer after all adjustments—the actual monthly payment one parent makes to the other.
Understanding Parenting Time Credit
The parenting time credit calculation often confuses parents because the credit percentage doesn't match the actual overnight percentage.
Why Credits Don't Match Overnight Percentages
Oregon's parenting time credit formula recognizes two competing realities:
Marginal Cost Reduction: When a parent has children overnight, they incur direct costs for food, utilities, transportation, and other immediate expenses. Parents with more overnights bear more of these costs, justifying reduced support obligations.
Fixed Cost Duplication: However, certain expenses—particularly housing—don't change based on occasional overnight visits. A parent with every-other-weekend parenting time still needs a bedroom for children, generating costs that aren't proportional to the small overnight percentage.
The guideline formula balances these factors by providing:
- Greater credit than the overnight percentage suggests when a parent has very limited time (recognizing fixed costs)
- Less credit than the overnight percentage suggests when parents approach equal time (recognizing that total costs exceed what either would pay alone)
- Proportional credit when parents share time exactly equally (50/50)
Impact on Support Obligations
Because of this non-linear credit structure, a parent with 40-45% parenting time might still pay some child support to the parent with 55-60% parenting time if both parents have similar incomes. This surprises parents who assume 50/50 income and nearly 50/50 parenting time would result in no support obligation.
Conversely, a parent with very limited parenting time (15-20%) receives more parenting time credit than their overnight percentage would suggest, partially recognizing the costs they incur maintaining a home where children can stay during their limited time.
Income Determination Special Situations
Determining income becomes complex in various situations requiring special treatment.
Self-Employment Income
Self-employed parents report gross business receipts minus ordinary and necessary business expenses, minus one-half of self-employment tax. However, certain deductions allowed for tax purposes aren't recognized for child support:
- Accelerated depreciation (though straight-line depreciation may be allowed)
- Investment tax credits
- Excessive or personal expenses claimed as business deductions
- Losses that appear designed to minimize support obligations
Courts closely scrutinize self-employment income, particularly when businesses show minimal income despite substantial time investment or when claimed expenses appear excessive relative to the business's nature.
Voluntary Underemployment
When parents voluntarily reduce income or refuse employment without good cause, courts may impute income based on earning potential rather than actual income. The calculator allows entering potential income figures when appropriate.
Good cause for reduced income includes:
- Physical or mental disability preventing work
- Incarceration (though child support obligations may continue)
- Caring for children too young for childcare while receiving other support
- Pursuing education or training expected to increase long-term earnings
Without good cause, courts can impute income based on:
- Recent work history and earnings
- Education, training, and qualifications
- Job opportunities and prevailing wages in the community
- Regional employment statistics showing typical earnings for similar workers
Minimum Wage Imputation
When parents don't work and earning capacity cannot be reliably determined, courts typically impute full-time minimum wage income. Oregon's minimum wage varies by region:
- Standard counties: $14.20/hour ($2,464/month full-time)
- Large counties (Portland metro): $15.45/hour ($2,678/month full-time)
- Rural counties: $13.20/hour ($2,288/month full-time)
Exceptions to minimum wage imputation include documented disability preventing work, incarceration, or caring for very young children while receiving assistance.
Irregular Income
Parents with variable income from commissions, bonuses, seasonal work, or irregular self-employment can use averaged income over 6-12 months to smooth fluctuations and determine a reasonable monthly support amount.
Deviations and Rebuttal Factors
While the calculator produces the presumptively correct support amount, Oregon law recognizes that special circumstances sometimes make guideline amounts unjust or inappropriate.
Rebuttal Factors Allowing Deviation
Oregon Administrative Rules identify specific rebuttal factors that may justify deviating from guideline amounts:
Special Needs of Children: Children with disabilities, chronic health conditions, or extraordinary educational needs may require support exceeding guideline amounts to cover additional expenses.
Special Needs of Parents: Parents with disabilities affecting earning capacity or creating extraordinary expenses may warrant deviation to account for these circumstances.
Extraordinary Costs of Parenting Time: When exercising parenting time requires substantial travel costs due to geographic distance, deviation may account for these expenses.
Relative Earning Capacity: In cases involving significant disparity in earning capacity where the higher-earning parent has substantially more parenting time, deviation may be appropriate.
High-Income Cases: When guideline amounts substantially exceed what parents at similar income levels typically spend on children, downward deviation may be warranted.
Other Factors: Any other factor deemed relevant to achieving a just and appropriate support amount may justify deviation if adequately explained.
15% Agreed Deviation
Parents can agree to support amounts deviating up to 15% from guideline calculations without proving rebuttal factors, as long as both voluntarily consent. This allows flexibility for parents who want round numbers or believe a slightly different amount better fits their circumstances.
For example, if the calculated support is $647, parents could agree anywhere from $550 to $744 without requiring court approval or explanation beyond their mutual agreement.
Modifying Support Based on Calculator Changes
As circumstances change, recalculating support using updated information determines whether modification is appropriate.
When to Recalculate
Run new calculations when:
- Either parent's income changes significantly (typically 10% or more)
- Parenting time schedules change substantially
- Health insurance costs or coverage changes
- Childcare expenses increase or decrease
- Children age out of childcare or develop new needs
- Additional children are born to either parent
Three-Year Review Right
Every three years from the date of the last support order, either parent can request administrative review through the Oregon Child Support Program without proving changed circumstances. The program recalculates support using current information and modifies the order if the new amount differs by at least 10% or $25 (whichever is greater).
Use the calculator with updated figures to determine whether requesting three-year review is likely to produce meaningful change.
Practical Tips for Accurate Calculations
Follow these best practices when using the Oregon child support calculator:
Use Monthly Figures: The calculator requires monthly amounts. Convert annual salaries to monthly (divide by 12), weekly wages to monthly (multiply by 4.33), and biweekly wages to monthly (multiply by 2.17).
Include All Income: Don't forget bonuses, commissions, overtime, investment returns, rental income, and other income sources beyond base salary.
Verify Insurance Costs: Contact HR for precise breakdowns of employee-only versus employee-plus-dependents costs rather than estimating.
Calculate Overnights Carefully: Map out your complete parenting plan for a full year including regular schedules, holidays, and summer vacation before counting overnights.
Document Everything: Save copies of calculations with notes about the date and information used, creating a record for comparison as circumstances change.
Consult Professionals: When calculations involve complex income issues, self-employment, or other complications, consult with family law attorneys or mediators for guidance.
Conclusion
The Oregon child support calculator at justice.oregon.gov/guidelines provides the standardized tool for calculating child support obligations based on Oregon's guideline formula incorporating parental incomes, parenting time percentages, health insurance costs, childcare expenses, and other relevant factors. Understanding how to enter information accurately, what each input field means, and how the calculator processes data to produce results ensures fair support amounts that meet children's needs while reflecting each parent's financial capacity and involvement.
While the calculator produces presumptively correct amounts used in most cases, judges and administrators retain authority to deviate when special circumstances warrant different support levels. Parents can also agree to amounts within 15% of guidelines without proving rebuttal factors, providing flexibility when mutual agreement exists.
Whether you're estimating potential support during divorce negotiations, preparing for a child support establishment hearing, or evaluating whether changed circumstances justify modification requests, the Oregon child support calculator provides the essential tool for understanding support obligations and ensuring children receive appropriate financial support from both parents.