Interest on Child Support Arrears in Arizona: Rate, Simple vs. Compound and When It Applies

By the FigureMyTax Editorial Team · How we calculate

The Arizona child support interest rate is 10% a year, simple, accruing only on the principal and not on interest. For arrears not yet in a written judgment it starts at the end of the month after the month the payment was due.

What is the child support interest rate in Arizona?

Ten percent a year, simple. In calculating support arrearages not reduced to a final written money judgment, interest accrues at ten percent a year beginning at the end of the month following the month in which the payment is due, and only on the principal, not on interest. A support arrearage reduced to a final written money judgment also accrues ten percent a year, on the principal only (A.R.S. 25-510(E)).

Is Arizona child support interest simple or compound?

Simple. The statute says interest accrues only on the principal and not on interest, so the Arizona arrears calculator never adds interest to the base.

When does interest start on unpaid Arizona child support?

Each installment vests when it falls due and is enforceable as a final judgment (A.R.S. 25-503(I)), but interest on arrears not yet in a written judgment starts at the end of the month following the due month. An installment due in March starts accruing at the end of April.

How much interest is that? A worked example

Monthly support of $500, one installment due each month, figured at the end of the month in which the newest installment is due:

An installment unpaid for 12 months after interest begins earns $50.00 on $500.

Is there interest on past support that was reduced to judgment?

Past support reduced to a final written money judgment beginning on September 26, 2008 under A.R.S. 25-320(C) or 25-809(B) does not accrue interest for any time period, while such past support reduced to judgment before that date accrues ten percent from entry of the judgment (25-510(F)).

What is the difference between arrears in a judgment and arrears not yet in one?

Each vested installment is already enforceable as a final judgment by operation of law, but the person owed support or the department can also file a request for a written judgment on the arrears (A.R.S. 25-503(I), (N)). Interest is 10% a year, simple, either way, but a written judgment gives a fixed figure to enforce and, in clearinghouse cases, past-due support reduced to judgment is paid before past-due support that is not.

In what order are payments applied?

In cases not enforced by the state, the support payment clearinghouse distributes money in this order: current child support, current spousal maintenance, the handling fee, past-due support reduced to judgment and its interest, past-due maintenance reduced to judgment and its interest, past-due support not reduced to judgment and its interest, and so on (25-510(A)). The current obligation must be fully met before an assignment pays arrears (25-503(D)).

Does the court consider interest when it sets the payment on arrears?

Yes. The court must consider all factors, including the accrual of interest on the arrears, and if it sets the payment at less than the accruing monthly interest it must find why (Guidelines Section XVI.B). A government agency’s arrearage calculator figure is presumed correct (25-510(I)).

What if you cannot pay?

If your circumstances changed, ask to modify the order now: only installments after notice can change. See also whether Arizona arrears expire or can be forgiven.

Frequently asked questions

Official sources

• A.R.S. 25-503: vested installments, judgment on arrearages, defenses
• A.R.S. 25-510: payments, arrearages and interest
• A.R.S. 25-518: arrearage and license suspension
• A.R.S. 25-320: support orders and assignment
• Arizona Child Support Guidelines, Section XVI: child support arrears
• 42 U.S.C. 652(k): denial of passports

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.