Child support in Idaho
Idaho uses the income-shares model: both parents' incomes count, and each parent pays a share of the child's support. To open a case, contact the Idaho Department of Health and Welfare, Child Support Services at 800-356-9868.
Checked against official sources: Oct 25, 2026. · Free letters and checklist ↓
How much child support 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:
Open a child support case in Idaho
- Phone
- 800-356-9868
- Apply
- Apply online
- How to open a case
Download the Child Support Services application (or ask for one by phone) and mail it with the $25 fee. Child Support Services calculates a proposed amount and files it with the court; either parent can respond, and the court sets the final amount. You can also file your own case in magistrate court using the Court Assistance Office forms.
- Application fee
$25 application fee for enforcement services, mailed with the application. Payment processing (receipting) only has no fee (Idaho DHW, fee list effective October 2025).
- Yearly fee
$35 annual federal receipting fee, as listed on the Department's fee schedule. The same schedule lists a $25 federal and state tax offset fee.
Source: page updated October 1, 2025
- Forms
- Paternity (legal fatherhood)
Parents can sign a voluntary acknowledgment of paternity, notarized and filed with the Vital Statistics Unit; it becomes a legal finding of paternity, and either party can rescind it within 60 days. Child Support Services can also establish paternity with genetic testing ($55 per person).
Law: Idaho Code 7-1106
Idaho child support by topic
How support is calculated in Idaho
The model, the percentages or the official calculator, and low-income rules.
Change child support in Idaho
When you can ask, how to ask, and a review letter.
Collect unpaid support in Idaho
Collection tools, interest and license rules, and a letter.
When support ends in Idaho
The end age, high school and disability rules.
How child support is figured in Idaho
- Model
- Income shares
- How it 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.
- Low income
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).
- Official calculator
- Official Idaho child support calculator
- Health insurance and medical costs
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.
Law: Idaho Rules of Family Law Procedure 120 (Idaho Child Support Guidelines); Idaho Code 32-706
Change a child support order in Idaho
- When a change is allowed
The court can change support only for a substantial and material change of circumstances, and only for payments due after the motion is filed. A change in the guideline amount may count as such a change (I.R.F.L.P. 120(d)). Child Support Services reviews an order after 3 years at either parent's request, or sooner if a substantial change has lasted at least 6 months.
Law: Idaho Code 32-709
- How to ask
Call Child Support Services at 800-356-9868 to ask for a review (fees may be charged), or file a Petition to Modify an Order, Judgment or Decree with the court. Use the Health and Welfare (H&W) versions of the forms if the Department was a party to your case.
Law: Idaho Code 32-709; I.R.F.L.P. 120(d)
Can I ask for a change? Check your situation
Collect unpaid child support in Idaho
Arrears means support that is past due. The child support agency can use these tools to collect it:
- Collection tools
- Income withholding
- Bank account garnishment
- Credit reporting
- Lottery winnings intercept
- Federal and state tax refund intercept
- Withholding federal benefits and retirement accounts (including PERSI)
- License suspension
- Liens
- Passport denial
- Judgments
- Contempt action
- License suspension
Unpaid support equal to at least 90 days of support, or $2,000, whichever is less.
Law: Idaho Code 7-1402(3), 7-1403
- Contempt of court
Child Support Services can bring a contempt action for nonpayment. Its fees for this range from $150 to $575 depending on how the case ends.
Law: Idaho Code 7-1401 to 7-1417 (license suspension)
When child support ends in Idaho
- Support ends
18. If the child is still in high school after turning 18, the court may order support to continue until the child leaves high school or turns 19, whichever comes first.
- Exceptions
The guidelines do not cover support for education after high school (I.R.F.L.P. 120(a)).
Law: Idaho Code 32-706(1)-(2)
When does support end? Check your situation
Free help in Idaho
- Idaho Legal Aid Services
- Idaho State Bar Lawyer Referral Service · (208) 334-4500
- Find free legal help at LawHelp.org
Official self-help
Free letters and checklist
Ask the agency to review (change) your order
A letter to the child support agency asking for a review and adjustment.
Ask the agency to collect unpaid support
A letter asking the agency to enforce the order and collect what is past due.
Checklist: what to bring to open a case
IDs, birth certificates, the other parent's details and your papers, with Idaho's agency contact.
Good to know in Idaho
- Idaho Child Support Services charges legal fees for its court work, for example $310 to $575 to establish or modify an order and $55 per person for genetic testing. These are usually set in the order and can be taken from future collections (DHW fee list, October 2025).
- A parent who has the child for more than 120 days with the other parent's consent may get a credit against arrears (Idaho Code 32-709(2)).
- A license can also be suspended for substantially failing to follow a visitation order (Idaho Code 7-1403).
Changes in 2024–2026
The Idaho Child Support Guidelines (I.R.F.L.P. 120) were amended June 3, 2025, effective July 1, 2025. Child Support Services published a new fee schedule effective October 2025.
Federal rules in every state
- Applying. If you don't get TANF, Medicaid or foster care help, a state may charge an application fee of up to $25 to open a child support case. Law: 42 U.S.C. 654(6)(B)(i)
- Yearly fee. If you never got TANF and the agency collected at least $550 for you in a year, the state charges a $35 yearly fee. It can come out of your support, but never out of the first $550. Law: 42 U.S.C. 654(6)(B)(ii)
- Review every 3 years. If your case is with the child support agency, either parent can ask it to review the order every 3 years and adjust it to the guidelines. Law: 42 U.S.C. 666(a)(10)(A); 45 CFR 303.8
- Past-due support. Each unpaid payment becomes a judgment on the day it is due. It can't be lowered later, except back to the date the other parent got notice of a request to change the order. Law: 42 U.S.C. 666(a)(9)
- Tax refunds. The federal government can take a federal tax refund to pay past-due child support. Law: 42 U.S.C. 664
- Passports. A parent who owes more than $2,500 in past-due support can be refused a passport. Law: 42 U.S.C. 652(k)
- Pay withholding limit. For support, up to 50% of take-home pay can be withheld if the parent supports another spouse or child, or 60% if not. It is 55% or 65% when support is more than 12 weeks behind. Law: 15 U.S.C. 1673(b)
- How long support lasts. How long support lasts follows the law of the state that made the order, even if you move. Law: 28 U.S.C. 1738B(h)(2)
Questions about child support in Idaho
How is child support calculated 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.
Is there an official child support calculator for Idaho?
What if the paying parent has a low income 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).
How do I apply for child support in Idaho?
Download the Child Support Services application (or ask for one by phone) and mail it with the $25 fee. Child Support Services calculates a proposed amount and files it with the court; either parent can respond, and the court sets the final amount. You can also file your own case in magistrate court using the Court Assistance Office forms.
Does it cost money to open a child support case in Idaho?
$25 application fee for enforcement services, mailed with the application. Payment processing (receipting) only has no fee (Idaho DHW, fee list effective October 2025).
Is there a yearly fee for child support services in Idaho?
$35 annual federal receipting fee, as listed on the Department's fee schedule. The same schedule lists a $25 federal and state tax offset fee.
When can child support be changed in Idaho?
The court can change support only for a substantial and material change of circumstances, and only for payments due after the motion is filed. A change in the guideline amount may count as such a change (I.R.F.L.P. 120(d)). Child Support Services reviews an order after 3 years at either parent's request, or sooner if a substantial change has lasted at least 6 months.
How do I ask to change child support in Idaho?
Call Child Support Services at 800-356-9868 to ask for a review (fees may be charged), or file a Petition to Modify an Order, Judgment or Decree with the court. Use the Health and Welfare (H&W) versions of the forms if the Department was a party to your case.
What happens if child support is not paid in Idaho?
Arrears means support that is past due. The child support agency can use these tools to collect it: Income withholding; Bank account garnishment; Credit reporting; Lottery winnings intercept; Federal and state tax refund intercept; Withholding federal benefits and retirement accounts (including PERSI); License suspension; Liens; Passport denial; Judgments; Contempt action.
Can a license be suspended for unpaid child support in Idaho?
Unpaid support equal to at least 90 days of support, or $2,000, whichever is less.
Can a parent be held in contempt for not paying in Idaho?
Child Support Services can bring a contempt action for nonpayment. Its fees for this range from $150 to $575 depending on how the case ends.
When does child support end in Idaho?
18. If the child is still in high school after turning 18, the court may order support to continue until the child leaves high school or turns 19, whichever comes first.
Does child support continue while my child finishes high school in Idaho?
If the child is still in high school after turning 18, the court may order support to continue until the child leaves high school or turns 19, whichever comes first.
Can child support continue past the usual age in Idaho?
The guidelines do not cover support for education after high school (I.R.F.L.P. 120(a)).
How is paternity established in Idaho?
Parents can sign a voluntary acknowledgment of paternity, notarized and filed with the Vital Statistics Unit; it becomes a legal finding of paternity, and either party can rescind it within 60 days. Child Support Services can also establish paternity with genetic testing ($55 per person).
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.
More help on our sister sites
Sources
- I.R.F.L.P. 120 Idaho Child Support Guidelines
- 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.
- State plan requirements: application fee, annual fee, safeguards, 42 U.S.C. 654
- Required state laws: arrears as judgments, review every 3 years, UIFSA, 42 U.S.C. 666
- Federal tax refund offset, 42 U.S.C. 664
- Passport denial for child support arrears, 42 U.S.C. 652(k)
- Garnishment limits for support orders, 15 U.S.C. 1673(b)
- Full faith and credit for child support orders, 28 U.S.C. 1738B
- Office of Child Support Enforcement (federal)