File your return electronically using My DOR. Simply log in to My DOR using your Secure Access Washington (SAW) user ID. You will need your tax account ID and letter ID, printed on correspondence from the Department, to sign up.
File by mail
You should receive a tax return in the mail approximately two weeks before the due date (businesses that are registered to file online will not receive a paper form in the mail). If you have misplaced yours, download a tax return from our site.
If you discover that you made a mistake on a previously filed tax return, you can amend your return. You may go back four years, plus the current year.
Depending on whether you file your return electronically or by mail, the Department offers several types of payment methods.