Ariz. Rev. Stat. § 23-743 – Limitations

A. Except as provided in subsections D and E of this section, additional contributions, payments in lieu of contributions, interest or penalties shall not be determined by the department to be due after three years from the date the contributions, payments in lieu of contributions, interest or penalties became delinquent.
B. An employer's obligation for any contributions, payments in lieu of contributions, interest or penalties that are required to be collected by the department for any period are extinguished, if not previously satisfied, six years after the amounts were determined due unless one of the following circumstances applies:
1. 1. The department has commenced civil action to collect the debt pursuant to section 23-737 or 23-737.01.
2. 2. The taxpayer has agreed in writing to extend the time period before the time period expires.
3. 3. An enforced collection has been stayed by the operation of federal or state law during the period. The period of limitations prescribed by this subsection is extended by the period of time that the department was stayed from engaging in enforced collections.
C. If a tax obligation is extinguished pursuant to subsection B of this section, any related liens for those obligations are also extinguished.
D. In case of failure without good cause to file a return, fraud or intent to evade any provision of this chapter, additional contributions, payments in lieu of contributions, interest or penalties shall not be determined by the department to be due after six years from the date the contributions, interest or penalties became delinquent.
E. Any amount of contributions, interest or penalties for wages and periods that are assessed by the internal revenue service as subject to the federal unemployment tax act against which credit may be taken for contributions required to be paid into a state unemployment fund by employers subject to the federal law shall be determined by the department to be due regardless of the date the contributions, payments in lieu of contributions, interest or penalties became delinquent.