- 13August 13, 1820No events
- 14August 14, 1820No events
- 15August 15, 1820No events
- 16August 16, 1820No events
- 17August 17, 1820No events
- 18August 18, 1820No events
- 19August 19, 1820No events
A=ANNUAL
M=MONTHLY
Q=QUARTERLY
DISCLAIMER: THESE DUE DATES ARE SUBJECT TO CHANGE. WE WILL DO OUR BEST TO KEEP THIS CALENDAR UP TO DATE WITH THE EVERCHANGING DEADLINES. ANY STATE FILING DUE DATES ARE IN REFERENCE SPECIFICALLY TO THE WASHINGTON STATE DEPARTMENT OF REVENUE.
