The Arizona Together initiative established by Governor Ducey connects individuals and businesses to resources, information, and volunteer opportunities to support Arizonans during the COVID-19 outbreak. Learn more, visit ArizonaTogether.org.
On January 1 of each year, the Arizona Department of Revenue (ADOR) will add any outstanding interest as of that date to the principal amount of tax still owed. This compounding interest is then calculated on the new tax principal amount.
The department applies interest, compounded annually, in the same manner and at the same time as prescribed by the U.S. Internal Revenue Code (IRC), Section 6621. However, that rate of interest for both overpayments and underpayments for all taxpayers is the federal short-term rate, determined by the IRC, plus three percentage points.