File Your State Sales Tax Returns Faster and Easier with Autofill Forms


You’re registered with the Washington Department of Revenue and you’ve begun collecting sales tax. Congratulations! Remember, those tax dollars don’t belong to you. As an agent of the state of Washington, your role is that of intermediary transferring tax dollars from consumers to state and local tax agencies. Let’s take a deeper look at how it happens.

What does it mean to file a Washington sales tax return?

Technically speaking, filing Washington sales tax returns is a two step process comprised of filing the necessary paperwork and remitting the collected tax dollars (if any) to state and local tax authorities.

To file the necessary paperwork, business owners are required to complete a Washington sales tax filing form. This can be done online (recommended) or, in some states, on paper. This process forces the business owner to detail their total sales, the amount of sales tax they have collected, and from where. The Washington Department of Revenue wants to be kept up to date on your business growth (or lack thereof) and make sure they are getting the tax dollars due. By completing ongoing filing of monthly, quarterly, or semi-annual, or annual business tax returns, they stay abreast of your changing company.

When am I required to file my sales tax return?

The Washington Department of Revenue will assign you a filing frequency. Typically, this is determined by the size of your business. State governments typically ask larger businesses to file more frequently. Visit our Washington filing due dates page for more information.

Am I required to file and pay my Washington sales tax at the same time?

Washington sales tax returns must be filed and paid at the same time and are governed by the same due date.

Can a 3rd party file my sales tax on my behalf?

Yes! Many business owners recognize they are not a tax professional and therefore, choose to outsource their sales tax sales and use tax filing to services like Avalara TrustFile or to an accountant or bookkeeper. This is a normal business practice that can save business owners time and help them avoid costly mistakes due to inexperience and a lack of deep knowledge about Washington sales tax code.

What happens if I file or pay my sales tax return late?

If outstanding sales tax is not paid to the Washington Department of Revenue by the assigned due date, you will be assessed a nine percent late penalty with the minimum penalty equaling $5.

If the tax liability remains outstanding after the month in which the taxes were do, the following late penalties will be assessed:

  • A 19 percent penalty will be due after the last day of the month following the return’s due date.
  • A 29 percent penalty will be due after the last day of the second month following the return’s due date.

Can I request a sales tax filing extension in Washington if I am unable to file on time?

Do I need to file a return if I didn’t collect any sales tax in Washington?

Yes! Once you’ve successfully registered for and been issued a Certificate of Registration, you are required to file at the completion of each assigned collection period regardless of whether any sales tax was collected. This is what is known as a “zero-tax filing”.

Failure to submit a required zero-tax filing can result in penalties imposed on your business by the Washington Department of Revenue so don’t take this responsibility lightly.

If I close my business, do I need to file a final sales tax return?

Yes! The Washington Department of Revenue requires all businesses to “close their books” by filing a final sales tax return. This also holds true for business owners selling or otherwise transferring ownership of their business.

Does the Washington Department of Revenue offer a discount for filing on time?

At this time, the Washington Department of Revenue does not offer sales tax filers a vendor discount.