- 25January 25, 1981No events
- 26January 26, 1981No events
- 27January 27, 1981No events
- 28January 28, 1981No events
- 29January 29, 1981No events
- 30January 30, 1981No events
- 31January 31, 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.