How child support is calculated in Idaho
The formula, the official tool, and the rules for low incomes and health insurance.
Checked against official sources: Oct 25, 2026.
Short answer
Idaho uses the income-shares model: both parents' incomes count, and each parent pays a share of the child's support. Both parents' gross incomes are added together. The guidelines take a set percentage of the combined income, with lower percentages at higher income levels, and each parent pays a share based on their part of the combined income.
- Model
- Income shares
- Official calculator
- Official Idaho child support calculator
Where the real number comes from in Idaho
Both parents' gross incomes are added together. The guidelines take a set percentage of the combined income, with lower percentages at higher income levels, and each parent pays a share based on their part of the combined income. Child care, health insurance and uninsured medical costs are shared in proportion to income. If the child spends more than 25% of overnights with each parent, a shared custody adjustment applies.
Law: Idaho Rules of Family Law Procedure 120 (Idaho Child Support Guidelines); Idaho Code 32-706
We don't estimate Idaho's amount here: its formula uses both parents' incomes and other facts, and a home-made number could mislead you. The official tool gives the real starting number:
How Idaho's formula works
Both parents' gross incomes are added together. The guidelines take a set percentage of the combined income, with lower percentages at higher income levels, and each parent pays a share based on their part of the combined income. Child care, health insurance and uninsured medical costs are shared in proportion to income. If the child spends more than 25% of overnights with each parent, a shared custody adjustment applies.
Law: Idaho Rules of Family Law Procedure 120 (Idaho Child Support Guidelines); Idaho Code 32-706
Medical support in Idaho
Every order must consider health insurance. It should come from the parent who can get appropriate employer coverage at the lower cost. Premiums and uninsured costs (such as dental, optical, orthodontic, counseling and prescriptions) are shared by the parents' income percentages (I.R.F.L.P. 120(g)(4)). Child Support Services can enroll a child in a parent's employer plan.
The model in plain words
In an income-shares state, both parents' incomes are added together. A table gives the support for that combined income, and each parent pays the share that matches their part of the income.
Every state must have one set of child support guidelines, review them at least every 4 years, and use the guideline amount unless a written finding says it would be unjust.
Law: 45 CFR 302.56
The low-income rule in Idaho
If the paying parent earns less than $800 a month, the court looks closely at income and living expenses so the parent keeps enough for basic self-support. There is a rebuttable presumption that support is at least $50 a month per child (I.R.F.L.P. 120).
State guidelines may not treat time in jail or prison as choosing not to work, when support is set or changed.
Law: 45 CFR 302.56(c)(3)
In nearby states
- Oregon: Income shares
- Washington: Income shares
- Wyoming: Income shares
- Utah: Income shares
From income to an order in Idaho
Gather income papers
Pay stubs, tax returns and benefit letters for both parents, if you have them.
Check the official calculator
The state's own tool gives the starting number: Official Idaho child support calculator.
Add the extra costs
The child's health insurance and child care costs can change the amount.
Ask for an order
The agency can set up an order: contact Idaho Department of Health and Welfare, Child Support Services (800-356-9868) · Apply online
Talk to legal aid
Free help: Idaho Legal Aid Services and Idaho State Bar Lawyer Referral Service.
Free help in Idaho
Questions about the Idaho guidelines
How does Idaho figure child support?
Both parents' gross incomes are added together. The guidelines take a set percentage of the combined income, with lower percentages at higher income levels, and each parent pays a share based on their part of the combined income. Child care, health insurance and uninsured medical costs are shared in proportion to income. If the child spends more than 25% of overnights with each parent, a shared custody adjustment applies.
Does Idaho have an online support calculator?
How does Idaho treat low incomes?
If the paying parent earns less than $800 a month, the court looks closely at income and living expenses so the parent keeps enough for basic self-support. There is a rebuttable presumption that support is at least $50 a month per child (I.R.F.L.P. 120).
Who pays for the child's health insurance in Idaho?
Every order must consider health insurance. It should come from the parent who can get appropriate employer coverage at the lower cost. Premiums and uninsured costs (such as dental, optical, orthodontic, counseling and prescriptions) are shared by the parents' income percentages (I.R.F.L.P. 120(g)(4)). Child Support Services can enroll a child in a parent's employer plan.
Keep reading about Idaho
Sources
- Idaho Rules of Family Law Procedure 120 (Idaho Child Support Guidelines); Idaho Code 32-706
- Idaho Code 32-706
- Idaho Code 32-709
- Idaho Code 7-1402 (delinquency definition)
- Idaho Code 7-1106 (acknowledgment of paternity)
- DHW: Child support fees
- DHW: Child support enforcement services
- DHW: Apply for services
Last checked: Oct 25, 2026.