How Idaho Calculates Child Support
Idaho runs combined yearly Guidelines Income through a bracket schedule (18% of the first $10,000 for one child, falling to 5%), rounds each bracket to the monthly dollar, splits the total by income share and has the parent with 25% or less of the overnights pay his or her share, plus a pro rata share of child care and insurance.
Step 1: Guidelines Income
Guidelines Income is the parent’s gross income before taxes, plus employment benefits and potential income where applicable, less the adjustments in the rule (Rule 120(e) and (f)). The worksheet uses monthly income, and the bracket schedule uses the yearly equivalent. See what income and deductions count.
Step 2: The bracket schedule
The basic child support obligation is built from the schedule in Rule 120(i)(1). For two children the first $10,000 of combined yearly income is charged at 26%, the next $10,000 at 25%, then 23%, 22% and 20% for each following $10,000, then 17%, 13%, 9%, 8% and 8% for each following $20,000, and 8% for the next $290,000. The monthly amount of each bracket is rounded to the dollar and the pieces are added. The rule’s own example, $35,000 of combined yearly income and two children, adds up to $709 a month.
Step 3: Each parent’s share
Each parent pays his or her percentage of the basic obligation, and the parent with 25% or less of the overnights is the one who pays. In the rule’s example the lower-time parent has 25,000 of the 35,000 of income, so pays 71%, or $506 of the $709.
Step 4: Child care and health insurance
The basic obligation does not cover work-related child care. The court may order a sharing in proportion to Guidelines Income, and health insurance premiums and uninsured health care costs are shared pro rata in addition to basic support, though the premium share can instead be built into the child support as a credit or an addition (Form 6, line 6).
A worked example
Two children live mostly with their mother (B), who earns $3,000 a month and pays $400 for child care. The father (A) earns $5,000, pays $150 for the children’s insurance and has 10% of the overnights.
| Item | Amount |
|---|---|
| Monthly gross income: paying parent (A) / other parent (B) | $5,000 / $3,000 |
| Combined Guidelines Income per year | $96,000 |
| Basic obligation, two children (bracket schedule) | $1,512 |
| A’s share (5,000 ÷ 8,000 = 62.5%) | $945 |
| Child care $400 paid by B and insurance $150 paid by A | $550 |
| A’s 62.5% share of the add-ons, less the $150 A already pays | $194 |
| A pays B each month (A has 10% of the overnights) | $1,139 |
Without child care and insurance, A’s share alone would be $945 a month. The Idaho child support calculator reproduces this example.
What to gather
The Affidavit Verifying Income with pay stubs and tax returns for both parents, child care invoices, the premium that covers the children and a calendar of the actual overnights. The court uses Form 6 for the standard calculation.
The $50 minimum
The Guidelines say support should rarely be set at zero. If the paying parent’s monthly income is below $800, the court reviews incomes and expenses to find the most that can be ordered without denying the parent a minimum subsistence level, and there is a rebuttable presumption of at least $50 a month per child.
Frequently asked questions
What are the Idaho child support brackets for one child?
18% of the first $10,000 of combined yearly income, then 17%, 15%, 14% and 13% of each next $10,000, then 12%, 9%, 6% and 5% of each next $20,000, and 5% of the next $290,000.
Does Idaho use gross or net income for child support?
Gross income before taxes, less the adjustments in Rule 120(f) such as other support and maintenance orders.
Is Idaho child support based on yearly or monthly income?
The bracket schedule is written on yearly income and the worksheets use monthly income; the monthly figure is multiplied by 12 to read the schedule.
Who pays child support in Idaho when one parent has 25% or less of the overnights?
That parent pays his or her percentage share of the basic obligation.
What form does Idaho use for the calculation?
Form 6, the Standard Child Support Worksheet, or Form 7 for shared, split or mixed custody.
Official sources
- Idaho Rules of Family Law Procedure, Rule 120: Idaho Child Support Guidelines
- Form 6: Standard Child Support Worksheet
- Form 7: Shared, Split or Mixed Custody Worksheet
A local family law attorney can review your situation — many offer a free consultation.
This is general information, not legal advice. It is based on the cited Idaho statutes, rules and court opinions, and every case turns on its own facts. Confirm how the law applies to your situation with a licensed Idaho attorney.