Wash. Admin. Code § 458-18-220 - Refunds-Rate of interest

(1) Introduction. Interest applies to refunds of taxes made pursuant to RCW 84.69.010 through 84.69.090 in accordance with RCW 84.69.100. Interest also applies to judgments entered in favor of the plaintiff pursuant to RCW 84.68.030.

(2) Calculation of interest rate. The interest rate is calculated from the equivalent coupon issue yield of the average bill rate for 26-week treasury bills as determined at the first bill market auction conducted after June 30th of the calendar year preceding the date the taxes were paid.

(3) Interest rates. The following rates are applied to the amount of the judgment or the amount of the refund, until paid:

Year tax	Auction
paid	Year	Rate
1984	1983	9.29%
1985	1984	11.27%
1986	1985	7.36%
1987	1986	6.11%
1988	1987	5.95%
1989	1988	7.04%
1990	1989	8.05%
1991	1990	8.01%
1992	1991	5.98%
1993	1992	3.42%
1994	1993	3.19%
1995	1994	4.92%
1996	1995	5.71%
1997	1996	5.22%
1998	1997	5.14%
1999	1998	5.06%
2000	1999	4.96%
2001	2000	5.98%
2002	2001	3.50%
2003	2002	1.73%
2004	2003	0.95%
2005	2004	1.73%
2006	2005	3.33%
2007	2006	5.09%
2008	2007	4.81%
2009	2008	2.14%
2010	2009	0.29%
2011	2010	0.21%
2012	2011	0.08%
2013	2012	0.15%
2014	2013	0.085%
2015	2014	0.060%
2016	2015	0.085%
2017	2016	0.340%
2018	2017	1.130%
2019	2018	2.085%
2020	2019	2.040%
2021	2020	0.165%
2022	2021	0.050%
2023	2022	2.50%
2024	2023	5.26%

Notes

Wash. Admin. Code § 458-18-220

Amended by WSR 14-01-059, filed 12/13/13, effective 1/1/2014 Amended by WSR 15-01-166, Filed 12/23/2014, effective 1/1/2015 Amended by WSR 16-01-035, Filed 12/9/2015, effective 1/1/2016 Amended by WSR 17-01-162, Filed 12/21/2016, effective 1/1/2017 Amended by WSR 18-01-147, Filed 12/20/2017, effective 1/1/2018 Amended by WSR 19-02-058, Filed 12/27/2018, effective 1/1/2019 Amended by WSR 20-02-056, Filed 12/24/2019, effective 1/1/2020 Amended by WSR 21-01-210, Filed 12/23/2020, effective 1/1/2021 Amended by WSR 22-04-028, Filed 1/24/2022, effective 1/1/2022 Amended by WSR 23-01-007, Filed 12/7/2022, effective 1/1/2023 Amended by WSR 24-03-001, Filed 1/3/2024, effective 1/3/2024

Statutory Authority: RCW 84.34.360, 84.34.065, 84.34.141, and 84.69.100. 13-02-053, § 458-18-220, filed 12/26/12, effective 1/1/13; 12-01-040, § 458-18-220, filed 12/13/11, effective 1/1/12. Statutory Authority: RCW 84.69.100. 11-02-017, § 458-18-220, filed 12/29/10, effective 1/1/11; 10-07-038, § 458-18-220, filed 3/10/10, effective 4/10/10; 08-24-094, § 458-18-220, filed 12/2/08, effective 1/2/09; 07-24-037, § 458-18-220, filed 11/30/07, effective 12/31/07; 06-21-059, § 458-18-220, filed 10/16/06, effective 11/16/06; 05-22-096, § 458-18-220, filed 11/1/05, effective 12/2/05; 04-24-101, § 458-18-220, filed 12/1/04, effective 1/1/05; 03-24-014, § 458-18-220, filed 11/20/03, effective 12/21/03; 02-23-081, § 458-18-220, filed 11/19/02, effective 12/20/02; 02-03-039, § 458-18-220, filed 1/8/02, effective 2/8/02; 00-24-106, § 458-18-220, filed 12/6/00, effective 12/31/00; 99-24-033, § 458-18-220, filed 11/23/99, effective 12/24/99. Statutory Authority: RCW 84.08.010, 84.08.070 and 84.69.100. 99-01-066, § 458-18-220, filed 12/14/98, effective 1/1/99; 98-01-177, § 458-18-220, filed 12/23/97, effective 1/1/98; 97-02-068, § 458-18-220, filed 12/31/96, effective 1/1/97; 96-01-093, § 458-18-220, filed 12/19/95, effective 1/1/96; 95-06-044, § 458-18-220, filed 2/24/95, effective 3/27/95; 94-05-063, § 458-18-220, filed 2/11/94, effective 3/14/94. Statutory Authority: RCW 84.08.010 and 84.69.100. 93-06-096, § 458-18-220, filed 3/3/93, effective 4/3/93; 92-17-027, § 458-18-220, filed 8/11/92, effective 9/11/92; 91-15-024, § 458-18-220, filed 7/11/91, effective 8/11/91. Statutory Authority: RCW 84.69.100 and 84.08.010(2). 89-10-067 (Order PT 89-6), § 458-18-220, filed 5/3/89; 88-07-003 (Order PT 88-3), § 458-18-220, filed 3/3/88. Statutory Authority: RCW 84.69.100 as amended by 1987 c 319 and 84.08.010(2). 87-19-141 (Order PT 87-7), § 458-18-220, filed 9/23/87.