Arizona Child Support Calculator (2025)

How Arizona Calculates Child Support

Arizona uses the Income Shares model for calculating child support, governed by ARS §25-320 (Arizona Revised Statutes) and the Arizona Child Support Guidelines. This model is based on the principle that children should receive the same proportion of parental income they would have received if the family remained intact. Arizona's guidelines were most recently updated in 2022 and represent a comprehensive approach to ensuring children receive adequate financial support from both parents.

The Arizona child support calculation begins by determining each parent's gross monthly income from all sources. Unlike some states that use net or adjusted income, Arizona starts with gross income, making the initial income determination relatively straightforward. Both parents' gross incomes are combined, and the combined figure is used to look up the basic child support obligation from the guidelines schedule.

One of the most distinctive features of Arizona's child support system is the parenting time adjustment. When the non-custodial parent has more than 92 days of parenting time per year (approximately 25% of the year), the child support obligation is adjusted downward to reflect the fact that the parent is directly paying for the child's expenses during their parenting time. This adjustment is particularly significant in cases where parents share parenting time relatively equally.

Overview of the Calculation Steps

The Arizona child support calculation follows a structured process that considers multiple factors:

1. Determine gross income for each parent from all sources
2. Make allowable adjustments such as court-ordered support for other children and spousal maintenance
3. Combine adjusted gross incomes to find the total combined income
4. Look up the basic support obligation from the guidelines schedule based on combined income and number of children
5. Allocate the obligation between parents based on their proportion of combined income
6. Apply the parenting time adjustment if the non-custodial parent has more than 92 days
7. Add additional expenses such as health insurance, childcare, and education costs, shared proportionally
8. Determine the final monthly obligation

Understanding ARS §25-320

Arizona Revised Statutes §25-320 is the primary statutory authority for child support in Arizona. This statute mandates that the Arizona Supreme Court establish child support guidelines and that those guidelines create a rebuttable presumption that the calculated amount is the correct amount of child support. The statute requires that the guidelines be reviewed at least every four years to ensure they remain current with economic research on child-rearing costs.

The guidelines themselves are contained in the Arizona Child Support Guidelines, which is a separate document adopted by the Arizona Supreme Court pursuant to ARS §25-320. The guidelines provide detailed instructions for calculating child support, including the income schedule, parenting time adjustment formulas, and provisions for additional expenses.

The Presumptive Nature of the Guidelines

Under ARS §25-320, the guideline amount is presumed to be the correct amount of child support. This means the court will apply the guideline calculation unless a party demonstrates that doing so would be inappropriate or unjust given the specific circumstances of the case. To overcome the presumption, the requesting party must present evidence showing why the guideline amount should not apply, and the court must make specific written findings supporting any deviation from the guidelines.

Arizona courts take the presumptive nature of the guidelines seriously. While deviations are permitted, they are not common and require substantial justification. This approach provides consistency and predictability in child support calculations throughout the state, while still allowing courts the flexibility to address unusual circumstances.

The Income Shares Model in Arizona

Arizona adopted the Income Shares model because economic research demonstrates that in intact families, both parents contribute to the costs of raising children in proportion to their respective incomes. The Income Shares model replicates this pattern when parents live separately by calculating what both parents would have spent on their children if they lived together, then allocating that amount between the parents based on their income shares.

Why Gross Income?

Arizona's decision to use gross income rather than net income simplifies the calculation process and reduces disputes over what constitutes a legitimate deduction. By starting with gross income, the guidelines avoid arguments about tax filing strategies, voluntary deductions, and other factors that can complicate net income calculations. The guidelines schedule accounts for typical tax burdens and necessary expenses, so the use of gross income does not result in inflated support amounts.

This approach also makes it easier for self-employed parents to calculate their income, as gross business income less necessary business expenses provides a clear starting point. It reduces the ability of parents to manipulate their child support obligation through creative accounting or by maximizing pre-tax deductions.

Gross Income Determination

Arizona defines gross income broadly for child support purposes. Understanding what counts as income is essential for an accurate calculation:

• Wages, salaries, and tips from all employment
• Commissions and bonuses
• Overtime pay (regular and recurring)
• Self-employment income (gross receipts minus ordinary and necessary business expenses)
• Severance pay
• Pension and retirement distributions
• Social Security benefits
• Unemployment insurance benefits
• Workers' compensation benefits
• Interest and dividend income
• Rental income (after reasonable expenses)
• Trust income
• Alimony/spousal maintenance received
• Capital gains
• Military pay and allowances

Adjustments to Gross Income

Arizona allows certain adjustments to gross income before combining the parents' incomes:

• Court-ordered child support paid for other children from a prior relationship
• Court-ordered spousal maintenance (alimony) paid
• Excess parenting time adjustment (calculated separately)

Imputed Income

Arizona courts can impute income to a parent who is voluntarily unemployed, underemployed, or who has recently reduced their income without a legitimate reason. When imputing income, the court considers the parent's work history, education, health, age, and the local job market. The court will assign an income level based on what the parent could reasonably be expected to earn. Arizona courts have consistently held that parents have a duty to maximize their earning potential for the benefit of their children, and deliberately reducing income to avoid child support obligations will not be tolerated.

Parenting Time Adjustment

The parenting time adjustment is one of the most significant features of Arizona's child support guidelines. This adjustment recognizes that when a parent has the children for a substantial portion of the year, they are directly paying for many of the children's expenses during that time, including food, housing, utilities, transportation, and entertainment.

The 92-Day Threshold

Arizona's parenting time adjustment kicks in when the non-custodial parent has more than 92 days of parenting time per year. This threshold represents approximately 25% of the year. Below 92 days, no adjustment is made and the standard calculation applies. Above 92 days, the adjustment increases as parenting time increases, up to the maximum of equal (50/50) parenting time.

The rationale for the 92-day threshold is that below this level, the custodial parent bears the vast majority of the children's direct costs and should receive the full guideline amount. Once the non-custodial parent passes the 92-day threshold, they are spending enough time with the children that their direct expenditures become significant enough to warrant a reduction in the support payment.

How the Adjustment Works

The parenting time adjustment reduces the non-custodial parent's child support obligation based on a formula that accounts for the proportion of time they have the children above the 92-day threshold. The adjustment is graduated, meaning it increases incrementally as parenting time increases. At 182.5 days each (50/50), the adjustment is at its maximum, and the calculation resembles a shared custody formula where the parent with higher income pays the difference in obligations to the other parent.

Equal Parenting Time

When parents have equal or nearly equal parenting time (approximately 50/50), the Arizona guidelines calculate each parent's support obligation separately and offset them against each other. The parent with the higher income pays the difference to the other parent. This approach ensures that even in 50/50 situations, the children benefit from both parents' incomes, while recognizing that each parent is directly supporting the children approximately half the time.

Arizona Support Schedule

The Arizona Child Support Guidelines include a detailed schedule that provides basic monthly child support obligations based on combined gross monthly income and number of children. Below is a representative sample of the schedule:

These amounts represent the total basic child support obligation that is then divided between the parents based on their respective shares of the combined gross income. The schedule amounts increase with income but at a decreasing rate, reflecting the economic reality that child-rearing costs do not increase linearly with income.

Deviation Factors

Arizona courts may deviate from the guideline amount when strict application would be inappropriate or unjust. Under the guidelines, deviation may be warranted for the following reasons:

• Extraordinary children's expenses not covered by the basic obligation, such as special medical needs, therapy, or educational programs
• Children's educational expenses for private school or special programs
• The age of the children, as older children typically cost more than younger children
• Income of the children from employment, trusts, or other sources
• Significant disparity in the parents' living standards
• The parent's financial resources and needs beyond typical expenses
• Seasonal fluctuations in income
• Destruction, concealment, or fraudulent disposition of community property
• Costs of transportation for parenting time when parents live far apart
• The best interests of the children

Modification of Arizona Child Support

Arizona child support orders can be modified when there has been a substantial and continuing change of circumstances. Under Arizona practice, a change that would result in at least a 15% difference from the existing order is generally considered substantial. Either parent can request modification through the court or through the Arizona Department of Economic Security (DES) Division of Child Support Services (DCSS).

Common grounds for modification include:

• Significant change in either parent's income (increase or decrease)
• Change in parenting time arrangement
• Change in the number of children requiring support
• Change in health insurance or childcare costs
• Emancipation of a child
• Child developing special needs
• Incarceration of the obligor
• Changes in the guidelines themselves (periodic updates)

The Modification Process

To modify child support in Arizona, a parent files a Petition to Modify Child Support with the Superior Court that issued the original order. The petition must allege a substantial and continuing change of circumstances and provide current financial information. The other parent is served with the petition and has the opportunity to respond. The court may hold a hearing or may decide the matter based on the paperwork alone if the facts are not in dispute.

Through DCSS, parents can also request an administrative review of their child support order every three years, or at any time if there has been a substantial change in circumstances. The administrative review process is generally faster and less expensive than going through the court system. DCSS will recalculate support using current income information and the current guidelines, and if the recalculated amount differs by 15% or more, DCSS will file a petition to modify the order.

Enforcement Mechanisms

Arizona provides robust enforcement mechanisms for child support obligations. The Department of Economic Security, Division of Child Support Services, is the primary enforcement agency:

• Income withholding: Automatic wage garnishment is mandated for all child support orders
• Tax refund interception: Federal and state tax refunds can be intercepted
• License suspension: Driver's, professional, and recreational licenses
• Contempt of court: Can result in fines or imprisonment
• Credit reporting: Arrearages reported to credit bureaus
• Passport denial: For arrearages over $2,500
• Property liens: On real and personal property
• Bank account levies: Funds seized from financial accounts
• Insurance settlement interception: Including workers' compensation

Interest on Arrearages

Arizona charges interest on past-due child support at the rate of 10% per year. This interest accrues from the date each payment was due and compounds the arrearage over time. Arizona courts generally do not have the authority to waive interest on child support arrearages, making it essential for obligors to stay current on their payments or to seek modification promptly when circumstances change.

Frequently Asked Questions

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