How it works · official guideline
How child support is calculated in Oregon
Oregon’s guidelines (OAR 137-050-0700 to -0765, with an Obligation Scale) look up a basic support obligation from both parents' combined adjusted gross income and the number of children, split it by income share, and subtract a parenting time credit computed from each parent’s overnights. A $1,729 self-support reserve and a $100 presumptive minimum order apply.[1]
Key facts: child support in Oregon
| Guideline model | Income shares[1] |
|---|---|
| Top of the guidelines | Scale tops out at $30,000 combined adjusted income per month[1] |
| Low income | Self-support reserve: $1,729 per month[1] |
| Minimum order | $100 per month presumptive minimum[1] |
| Guideline last checked | October 26, 2026 |
Oregon’s model
Income shares
Combined adjusted gross income, then obligation scale amount, split by income share, with a formula-based parenting time credit.
No official calculator confirmed yet
Read the guideline: OAR 137-050-0700The state child support agency or your court clerk can run the official numbers.
Why no calculator here? We publish a calculator only after it reproduces the state’s official numbers exactly. We haven’t matched Oregon’s yet.
From the official text
The rules behind Oregon’s numbers
The guideline is OAR 137-050-0700. Open each rule to read the exact words.
- Top of the guidelines
Scale tops out at $30,000 combined adjusted income per month
If combined adjusted gross income is over $30,000 a month, the basic obligation is the same as at $30,000; incomes between scale rows use the lower row.[1]
Official text · OAR 137-050-0725(3)
“If the combined adjusted gross income of the parents is more than $30,000 per month, the basic child support obligation is the same for parents with combined adjusted income of $30,000 per month.”
- Low income
Self-support reserve: $1,729 per month
The reserve of $1,729 is subtracted from a paying parent’s adjusted income to find what is available for support, and total support may not exceed that amount (except for the minimum order).[1]
Official text · OAR 137-050-0745(2)
“To determine the amount of the parent’s income available for support, subtract the self- support reserve of $1,729 from the parent’s adjusted income.”
- Minimum order
$100 per month presumptive minimum
A paying parent is presumed able to pay at least $100 a month in total support, with listed exceptions (for example, exactly equal 182.5 overnights each).[1]
Official text · OAR 137-050-0755(1)
“it is rebuttably presumed that an obligated parent is able to pay at least $100 per month as child support.”
- Shared parenting time
Parenting time credit by formula from overnights (no threshold)
Each parent’s parenting time credit percentage comes from a published formula based on average annual overnights; that percentage is applied to the children’s share of the basic obligation.[1]
Official text · OAR 137-050-0730(6)
“Determine each parent's parenting time credit percentage as follows: credit percentage=1/(1+e^(-7.14*((overnights/365)-0.5)))-2.74%+(2*2.74%*(overnights/365)).”
- Income counted
Actual or potential gross income, adjusted
Income means each parent’s actual or potential gross income, then adjusted (for example for support of other children) before the scale is used.[1]
Official text · OAR 137-050-0715(1)
““Income” means the actual or potential gross income of a parent as determined in this rule.”
Guideline: OAR 137-050-0700 (Oregon DOJ Child Support Guideline Rules with commentary, effective July 1, 2026), checked October 26, 2026.
Estimate and general information only — not legal advice. MediationList is a directory, not a law firm, and doesn’t endorse any mediator. Guidelines change; confirm with the state child support agency or your court (sources checked October 26, 2026). See also divorce laws in Oregon and child support in every state.
Sources
Oregon’s child support guideline, rules and official tools, read on the official sites, with the date we checked each.