- 11January 11, 1981No events
- 12January 12, 1981No events
- 13January 13, 1981No events
- 14January 14, 1981No events
- 15January 15, 1981No events
- 16January 16, 1981No events
- 17January 17, 1981No 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.