701—10.2 (421) Interest. Except where a different rate of interest is provided by Title X of the Iowa Code, the rate of interest on interest-bearing taxes and interest-bearing refunds arising under Title X is fixed for each calendar year by the director. In addition to any penalty computed, there shall be added interest as provided by law from the original due date of the return. Any portion of the tax imposed by statute which has been erroneously refunded and is recoverable by the department shall bear interest as provided in Iowa Code section 421.7, subsection 2, from the date of payment of the refund, considering each fraction of a month as an entire month. Interest which is not judgment interest is not payable on sales and use tax, local option tax, and hotel and motel tax refunds. Herman M. Brown v.	Johnson, 248 Iowa 1143, 82 N.W.2d 134 (1957); United Telephone Co.	v.	Iowa Department of Revenue, 365 N.W.2d 647 (Iowa 1985). However, interest which is not judgment interest accrues on such refunds on or after January 1, 1995, and is payable on sales and use tax, local option tax and hotel and motel tax refunds on or after January 1, 1995.
	 10.2(1) Calendar year 1982. The rate of interest upon all unpaid taxes which are due as of January 1, 1982, will be 17 percent per annum (1.4% per month). This interest rate will accrue on taxes which were due and unpaid as of, or after, January 1, 1982. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before, on, or after January 1, 1982. This interest rate of 17 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1982.
Examples:
	  1. 	 The taxpayer, X corporation, owes corporate income taxes assessed to it for the year 1975. The assessment was made by the department in 1977. On January 1, 1982, that assessment had not been paid. The rate of interest on the unpaid tax assessed has accrued at the rate of 9 percent per annum (0.75% per month) through December 31, 1981. Commencing on January 1, 1982, the rate of interest on the unpaid tax will thereafter accrue at the rate of 17 percent per annum for 1982 (1.4% per month). If the tax liability is not paid in 1982, the rate of interest will then accrue in 1983 in accordance with the rate fixed by the director as set forth in Iowa Code section 421.7.
	  2. 	 The taxpayer, Y, owes retail sales taxes assessed to it for the audit period January 1, 1979, through December 31, 1982. The assessment is made on March 1, 1983. For the tax periods in which the tax became due prior to January 1, 1982, the interest rate on such unpaid sales taxes accrued at 9 percent per annum (0.75% per month). Commencing on January 1, 1982, the entire unpaid portion of the tax assessed which was delinquent at that time will begin to accrue interest at the rate of 17 percent per annum. Those portions of the tax assessed first becoming delinquent in 1982 will bear interest at the rate of 17 percent per annum (1.4% per month). In the event that any portion of the tax assessed remains unpaid on January 1, 1983, the rate of interest will then accrue in 1983 in accordance with the rate fixed by the director as set forth in Iowa Code section 421.7.
	  3. 	 The taxpayer, Z, files a refund claim for 1978 individual income taxes in March 1982. The refund claim is allowed in May 1982, and is paid. Z is entitled to receive interest at the rate of 9 percent per annum (0.75% per month) upon the refunded tax accruing through December 31, 1981, and is entitled to interest at the rate of 17 percent per annum (1.4% per month) upon such tax from January 1, 1982, until the refund is paid.
	  4. 	 A’s 1981 individual income tax liability becomes delinquent on May 1, 1982. A owes interest, commencing on May 1, 1982, at the rate of 17 percent per annum (1.4% per month). In the event that A does not pay the liability in 1982, the rate of interest will then accrue in 1983 in accordance with the rate fixed by the director as set forth in Iowa Code section 421.7.
	  5. 	 Decedent died December 15, 1976. The inheritance tax was due 12 months after death, or December 15, 1977. Prior to the due date, the estate was granted an extension of time, until September 1, 1978, to file the return and pay the tax due. The tax, however, was paid March 15, 1982. Interest accrues on the unpaid tax during the period of the extension of time (December 15, 1977, to September 1, 1978) at the rate of 6 percent per annum. Interest accrues on the delinquent tax from September 1, 1978, through December 31, 1981, at the rate of 8 percent per annum. Interest accrues on the delinquent tax from January 1, 1982, to the date of payment on March 15, 1982, at the rate of 17 percent per annum.
	  6. 	 B files a refund for sales taxes paid for the periods January 1, 1979, through December 31, 1982, in March 1983. The refund is allowed in May 1983. Since no interest is payable on sales tax refunds, B is not entitled to any interest. Herman M. Brown Co.	v.	Johnson, 248 Iowa 1143 (1957). However, interest accrues and is payable on and after January 1, 1995.
The examples set forth in these rules are not meant to be all-inclusive. In addition, other rules set forth the precise circumstance when interest begins to accrue and whether interest accrues for each month or fraction of a month or annually as provided by law. Interest accrues as provided by law, regardless of whether the department has made a formal assessment of tax.
	 10.2(2) Calendar year 1983. The rate of interest upon all unpaid taxes which are due as of January 1, 1983, will be 14 percent per annum (1.2% per month). This interest rate will accrue on taxes which were due and unpaid as of, or after January 1, 1983. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before, on, or after January 1, 1983. This interest rate of 14 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1983.
	 10.2(3) Calendar year 1984. The rate of interest upon all unpaid taxes which are due as of January 1, 1984, will be 9 percent per annum (0.8% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 1984. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before, on, or after January 1, 1984. This interest rate of 9 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1984.
	 10.2(4) Calendar year 1985. The rate of interest upon all unpaid taxes which are due as of January 1, 1985, will be 10 percent per annum (0.8% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 1985. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before, on, or after January 1, 1985. This interest rate of 10 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1985.
	 10.2(5) Calendar year 1986. The interest upon all unpaid taxes which are due as of January 1, 1986, will be 9 percent per annum (0.8% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 1986. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before, on, or after January 1, 1986. This interest rate of 9 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1986.
	 10.2(6) Calendar year 1987. The interest upon all unpaid taxes which are due as of January 1, 1987, will be 9 percent per annum (0.8% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after January 1, 1987. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before, on, or after January 1, 1987. This interest rate of 9 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1987.
	 10.2(7) Calendar year 1988. The interest upon all unpaid taxes which are due as of January 1, 1988, will be 8 percent per annum (0.7% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after January 1, 1988. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before, on, or after January 1, 1988. This interest rate of 8 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1988.
	 10.2(8) Calendar year 1989. The interest upon all unpaid taxes which are due as of January 1, 1989, will be 9 percent per annum (0.8% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after January 1, 1989. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before, on, or after January 1, 1989. This interest rate of 9 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1989.
	 10.2(9) Calendar year 1990. The interest upon all unpaid taxes which are due as of January 1, 1990, will be 11 percent per annum (0.9% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after January 1, 1990. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before, on, or after January 1, 1990. This interest rate of 11 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1990.
	 10.2(10) Calendar year 1991. The interest upon all unpaid taxes which are due as of January 1, 1991, will be 12 percent per annum (1.0% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 1991. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before, on, or after January 1, 1991. This interest rate of 12 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1991.
	 10.2(11) Calendar year 1992. The interest upon all unpaid taxes which are due as of January 1, 1992, will be 11 percent per annum (0.9% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 1992. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before, on, or after January 1, 1992. This interest rate of 11 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1992.
	 10.2(12) Calendar year 1993. The interest upon all unpaid taxes which are due as of January 1, 1993, will be 9 percent per annum (0.8% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 1993. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before, on, or after January 1, 1993. This interest rate of 9 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1993.
	 10.2(13) Calendar year 1994. The interest upon all unpaid taxes which are due as of January 1, 1994, will be 8 percent per annum (0.7% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 1994. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before, on, or after January 1, 1994. This interest rate of 8 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1994.
	 10.2(14) Calendar year 1995. The interest upon all unpaid taxes which are due as of January 1, 1995, will be 9 percent per annum (0.8% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 1995. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before, on, or after January 1, 1995. This interest rate of 9 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1995.
	 10.2(15) Calendar year 1996. The interest upon all unpaid taxes which are due as of January 1, 1996, will be 11 percent per annum (0.9% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 1996. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before, on, or after January 1, 1996. This interest rate of 11 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1996.
	 10.2(16) Calendar year 1997. The interest rate upon all unpaid taxes which are due as of January 1, 1997, will be 10 percent per annum (0.8% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 1997. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before or after January 1, 1997. This interest rate of 10 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1997.
	 10.2(17) Calendar year 1998. The interest rate upon all unpaid taxes which are due as of January 1, 1998, will be 10 percent per annum (0.8% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 1998. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before or after January 1, 1998. This interest rate of 10 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1998.
	 10.2(18) Calendar year 1999. The interest rate upon all unpaid taxes which are due as of January 1, 1999, will be 10 percent per annum (0.8% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 1999. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before or after January 1, 1999. This interest rate of 10 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 1999.
	 10.2(19) Calendar year 2000. The interest rate upon all unpaid taxes which are due as of January 1, 2000, will be 10 percent per annum (0.8% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 2000. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before or after January 1, 2000. This interest rate of 10 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 2000.
	 10.2(20) Calendar year 2001. The interest rate upon all unpaid taxes which are due as of January 1, 2001, will be 11 percent per annum (0.9% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 2001. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before or after January 1, 2001. This interest rate of 11 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 2001.
	 10.2(21) Calendar year 2002. The interest rate upon all unpaid taxes which are due as of January 1, 2002, will be 10 percent per annum (0.8% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 2002. In addition, this interest rate will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before or after January 1, 2002. This interest rate of 10 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 2002.
	 10.2(22) Calendar year 2003. The interest rate upon all unpaid taxes which are due as of January 1, 2003, will be 7 percent per annum (0.6% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 2003. In addition, this interest will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before or after January 1, 2003. This interest rate of 7 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 2003.
	 10.2(23) Calendar year 2004. The interest rate upon all unpaid taxes which are due as of January 1, 2004, will be 6 percent per annum (0.5% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 2004. In addition, this interest will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before or after January 1, 2004. This interest rate of 6 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 2004.
	 10.2(24) Calendar year 2005. The interest rate upon all unpaid taxes which are due as of January 1, 2005, will be 6 percent per annum (0.5% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 2005. In addition, this interest will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before or after January 1, 2005. This interest rate of 6 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 2005.
	 10.2(25) Calendar year 2006. The interest rate upon all unpaid taxes which are due as of January 1, 2006, will be 8 percent per annum (0.7% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 2006. In addition, this interest will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before or after January 1, 2006. This interest rate of 8 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 2006.
	 10.2(26) Calendar year 2007. The interest rate upon all unpaid taxes which are due as of January 1, 2007, will be 10 percent per annum (0.8% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 2007. In addition, this interest will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before or after January 1, 2007. This interest rate of 10 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 2007.
	 10.2(27) Calendar year 2008. The interest rate upon all unpaid taxes which are due as of January 1, 2008, will be 10 percent per annum (0.8% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 2008. In addition, this interest will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before or after January 1, 2008. This interest rate of 10 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 2008.
	 10.2(28) Calendar year 2009. The interest rate upon all unpaid taxes which are due as of January 1, 2009, will be 8 percent per annum (0.7% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 2009. In addition, this interest will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before or after January 1, 2009. This interest rate of 8 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 2009.
	 10.2(29) Calendar year 2010. The interest rate upon all unpaid taxes which are due as of January 1, 2010, will be 5 percent per annum (0.4% per month). This interest rate will accrue on taxes which are due and unpaid as of, or after, January 1, 2010. In addition, this interest will accrue on tax refunds which by law accrue interest, regardless of whether the tax to be refunded is due before or after January 1, 2010. This interest rate of 5 percent per annum, whether for unpaid taxes or tax refunds, will commence to accrue in 2010.
This rule is intended to implement Iowa Code section 421.7.
[ARC 8551B, IAB 2/24/10, effective 3/31/10]