Late payment: 9%, then 19%, then 29%.
If Washington state tax is not received by the due date the penalty is 9 percent, rising to a total of 19 percent after the end of the next month and a total of 29 percent after that, with a minimum penalty of five dollars (RCW 82.32.090).
Transcript
Sal If tax isn't received by the Department of Revenue on the due date, Washington adds a nine percent penalty. Miss the end of the next month and the total goes to nineteen percent, and later than that, twenty-nine percent in total. No penalty can be less than five dollars.