Child Support

How Arizona calculates child support

Child support is governed by A.R.S. § 25-320 and the Arizona Child Support Guidelines. Arizona uses an income shares model: the guidelines estimate what the parents would spend on the child if the household were intact, then divide that obligation between them in proportion to their incomes. The result is a presumptive amount — the court orders it unless applying the guidelines would be inappropriate or unjust in a specific case.

What counts as income

Gross income under the guidelines is broader than a paycheck. It includes salaries and wages, commissions and bonuses, self-employment income, rental income, spousal maintenance received, and recurring gifts or prizes. If a parent is unemployed or working below their ability by choice, the court can attribute income to them and calculate support as if they were earning it. Documenting income accurately — especially self-employment income — is where many child support disputes are actually decided.

Adjustments that change the number

The calculation also accounts for the cost of the child’s medical, dental and vision insurance, childcare costs, the number of parenting-time days each parent exercises, and support paid for children of other relationships. Because parenting time directly affects the amount, child support and legal decision-making and parenting time are usually resolved together.

Modification

A child support order can be modified when there has been a substantial and continuing change in circumstances — a job loss, a significant change in either parent’s income, a change in the parenting schedule, or a change in the child’s needs. Under the guidelines, a difference of fifteen percent or more between the existing order and the amount the guidelines would produce today is treated as evidence of such a change. Until the court modifies it, the existing order stays fully enforceable — falling behind while waiting to file is one of the most common and most expensive mistakes.

Enforcement

When a parent does not pay, the order can be enforced through an income withholding order served on their employer, interception of tax refunds, liens, suspension of driver and professional licenses, and contempt proceedings. Unpaid support becomes a judgment by operation of law, accrues interest, and cannot be discharged in bankruptcy. Whether you are owed support or behind on it, the earlier an attorney is involved, the more options remain open.

When child support ends

Support ordinarily continues until the child turns eighteen — or, if the child is still attending high school at eighteen, until graduation or age nineteen, whichever comes first. Support can continue longer for a child with a disability. It does not automatically stop when circumstances change; the paying parent must ensure the order is properly terminated.

Child support questions rarely arrive alone — they come with a divorce, a custody dispute, or an enforcement problem years after the decree. Child support is one part of our family law practice, and we handle it with the same preparation we bring to every case.