How Arizona Calculates Child Support

By the FigureMyTax Editorial Team · How we calculate

Arizona uses the income shares model. The court adds both parents’ incomes, finds the basic obligation in the schedule, adds adjustments for older children, medical insurance and child care, divides the total by each parent’s share of the income, and reduces the paying parent’s share for parenting time and costs already paid.

Step 1: Child Support Income

Each parent’s income from any source before deductions counts, and the court then deducts court-ordered spousal maintenance actually paid and court-ordered child support actually paid for children of other relationships (Section II). The two Adjusted Child Support Incomes are added to get the Combined Adjusted Child Support Income. See what income counts for Arizona child support.

Step 2: The Basic Child Support Obligation

The court finds the combined income in the Schedule of Basic Support Obligation and reads across to the number of children. The schedule runs from $750 to $30,000 in $50 steps for one to six children. If the combined income falls exactly between two entries, the guidelines round up: $8,125 uses the $8,150 entry. Above $30,000 the $30,000 figure applies unless a party asks the court to consider more; for more than six children, the six-child figure is the presumptive amount (Section III.A).

Step 3: Adjustments that increase the obligation

The basic obligation is increased by 10% for children age 12 or older, prorated when only some children qualify: with a basic obligation of $810 for three children and one child over 12, one third ($270) is increased by 10%, adding $27. A child qualifies the day after turning 12. The cost of medical, dental and vision insurance attributable to the children and work-related child care are added next, along with any agreed education expenses and extraordinary child expenses (Section III.B).

Step 4: Dividing the obligation

Each parent’s share is that parent’s Adjusted Child Support Income divided by the combined figure, multiplied by the Combined Child Support Obligation (Section IV).

Step 5: Parenting time and costs paid

The days of parenting time are converted to a percentage with the Parenting Time Table, multiplied by the basic obligation including the older child adjustment, and subtracted from the share of the parent whose time is counted. A parent who pays insurance or child care directly deducts those costs from his or her share (Sections V and VI). The next post covers the parenting time adjustment.

Step 6: Who pays, and the self-support reserve

A positive result means the parent with less parenting time pays; with essentially equal time, the parent with the higher income pays. A negative result means the other parent pays, even if that parent has more income or time. The final award is rounded to the nearest whole dollar (Section X). The self-support reserve test then subtracts 80% of full-time minimum wage earnings from the paying parent’s income; if less than the award remains, the court may reduce the order (Section VIII).

A worked example

Two children, one of them 13. Parent A earns $5,500 a month and has the children 80 days a year; Parent B earns $3,000, has them 285 days and pays $200 a month for the children’s insurance and $300 for child care.

The Arizona child support calculator reproduces this example with the same numbers. The court’s computer worksheet may round intermediate steps differently, so its result can differ by a dollar or two.

Frequently asked questions

Official sources

• Arizona Child Support Guidelines (Administrative Order 2022-116)
• Arizona Judicial Branch: Child Support Guidelines

This is general information, not legal advice. It is based on the cited Arizona statutes, rules and court opinions, and every case turns on its own facts. Confirm how the law applies to your situation with a licensed Arizona attorney.