It's important to know when your taxes need to be filed. Here you can check your filing due dates to make sure your tax return gets in on time.Learn more about your options for paying, setting up a payment plan, mitigating, or contesting your traffic infraction, also called a citation or ticket. Due Dates, Late Fees and Interest. Tuition, mandatory fees, course fees, on-campus housing and meal plan charges are due on the first day of each term. Seattle businesses that file their city taxes annually now have until April 30 each year to file returns and submit payments due. For your convenience, Washington State law allows you to make two half payments.