How Arizona Calculates Child Support
Arizona uses the Income Shares model to determine child support obligations. This page explains the guidelines, formula, and key factors.
Model Type
Income Shares
Income-shares schedule based on combined adjusted gross income of both parents and number of children; each parent's obligation is prorated by income share; adjusted for parenting time and add-ons (childcare, health insurance, education expenses).
Income Basis & Definitions
gross
Selects the base-support amount from the schedule/table.
Source: A.R.S. § 25-320, Appendix: Schedule of Basic Support ObligationsParent A gross income used by guideline.
Source: A.R.S. § 25-320(5): Gross income definitionParent B gross income used by guideline.
Source: A.R.S. § 25-320(5): Gross income definitionParenting Time Handling
Calculator selects custody model/worksheet and applies corresponding formula.
Source: A.R.S. § 25-320(11): Parenting time adjustmentParenting time entered as number of days per year with each parent.
Source: A.R.S. § 25-320(11): Parenting time adjustment formulaDeductions & Adjustments
Court-ordered support for other children deducted from gross income.
Source: A.R.S. § 25-320(8): Adjustments for other childrenSpousal maintenance paid or received adjusts gross income.
Source: A.R.S. § 25-320: Spousal maintenance adjustmentAdd-Ons & Allocation
Work-related childcare costs added and allocated between parents.
Source: A.R.S. § 25-320(9): Childcare costsChild's health insurance premium share and uninsured/unreimbursed medical allocation.
Source: A.R.S. § 25-320(10): Health insurance and medical expensesCaps, Minimums & Deviations
Schedule caps at a combined income level; above-cap is court discretion.
Source: A.R.S. § 25-320: Maximum schedule income / above-cap handlingDeviation allowed for enumerated factors; requires written findings.
Source: A.R.S. § 25-320(20): Deviation criteria