Skip to main content
Starting October 1: Some business services are now subject to retail sales tax, as required by state law, ESSB 5814. When you buy these services, vendors should add sales tax to your bill. If you sell these services, you should begin collecting retail sales tax. Learn more about Services newly subject to retail sales tax.
Oil spill tax returns
Monthly
Note: Effective March 2018, the monthly Oil spill tax return was discontinued.
| 2018 | 2017 | 2016 | 2015 | 2014 | 2013 | |
|---|---|---|---|---|---|---|
| December | Return | Return | Return | Return | Return | |
| November | Return | Return | Return | Return | Return | |
| October | Return | Return | Return | Return | Return | |
| September | Return | Return | Return | Return | Return | |
| August | Return | Return | Return | Return | Return | |
| July | Return | Return | Return | Return | Return | |
| June | Return | Return | Return | Return | Return | |
| May | Return | Return | Return | Return | Return | |
| April | Return | Return | Return | Return | Return | |
| March | Return | Return | Return | Return | Return | |
| February | Return | Return | Return | Return | Return | Return |
| January | Return | Return | Return | Return | Return | Return |