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If you’re selling digital services and products to customers in Washington, then you might be liable for Washington’s sales tax. We’ve compiled over 10 years of experience in tax compliance to create this comprehensive guide, which covers how to file sales tax returns online and stay compliant with the state's regulations.
We’ve scoured the Washington Department of Revenue (DOR) website to provide you with all the necessary information about sales tax for businesses in one convenient place.
How to file sales tax returns in Washington
Sales and taxes should be reported and filed using US dollars. If you’ve made any transactions in Washington in a different currency, be sure to convert those to USD using official currency exchange rates.
When to file and pay
The DOR will assign you a filing frequency (monthly, quarterly, or yearly) after you register your business. Typically, this is determined by the size or sales volume of your business. State governments generally ask larger businesses to file more frequently.
Washington sales tax returns and payments must be remitted at the same time; both have the same due date. The Washington DOR requires all sales tax filing to be completed by the last day of the month following the assigned filing period. Due dates falling on a weekend or holiday are adjusted to the following business day.
WA sales tax filing deadlines
Monthly filing due dates
Reports are due on the 25th day of the month following the reporting month. For example, the July sales tax report is due August 25.
| Month | Filing Deadline |
|---|---|
| January | February 25 |
| February | March 25 |
| March | April 25 |
| April | May 25 |
| May | June 25 |
| June | July 25 |
| July | August 25 |
| August | September 25 |
| September | October 25 |
| October | November 25 |
| November | December 25 |
| December | January 25 |
Quarterly filing due dates
Reports are due on the last day of the month following the reporting period.
- April 30, for first quarter ending March 31
- July 31, for second quarter ending June 30
- October 31, for third quarter ending September 30
- January 31, for fourth quarter ending December 31
| Quarter | Filing Deadline |
|---|---|
| Q1 (January 1–March 31) | April 30 |
| Q2 (April 1–June 30) | July 31 |
| Q3 (July 1–September 30) | October 31 |
| Q4 (October 1–December 31) | January 31 |
Yearly filing due dates
Reports for the previous year are due on January 31.
Important Note: Zero Returns and No Business Activity
Even if you didn’t make any sales in Washington during your reporting period, you must still file a "zero return." This follows the exact same process as a normal return, just with no tax liability to report. Failure to submit a zero return can result in penalties and interest charges.
How to prepare your Washington sales tax return
Before you start working on your sales tax return, you'll need to collect all the sales information for your tax period. The DOR online tax return system will guide you, but generally, you'll need the following details:
Sales transactions
Every business needs to know how much it sold—both in gross sales and in taxable sales—and to whom the business sold it. You are also required to collect and pay sales tax for any personal property sold to residents of Washington, with certain exceptions (e.g., if the buyer has a resale certificate or the item isn't considered taxable).
In addition to your gross Washington sales (total sales revenue from buyers in Washington, regardless of taxability), filing a sales tax return requires the following information:
- Total sales and income
- Total purchases and expenses
- Taxable sales by type: Different types of products are subject to different tax rules and amounts.
- Non-taxable sales by type: Examples include sales to resellers, non-taxable labor, and certain non-taxable foods.
- Deductions: This might include items such as delivery charges.
- Total collected sales tax: The total amount of sales tax you collected from customers during the filing period.
How to complete and file a Washington sales tax return
The final step is to file and remit tax. The DOR has an online filing system where you can enter your information to generate the return. You can log in to My DOR with your SAW account information. In the Excise Tax Return panel, click the “File Return” link.
How to pay
Tax payments must be in US dollars and can be made directly at the time of filing. Once you’ve completed the return, you’ll remit the total calculated sales taxes.
Payment options include:
- Automated Clearing House (ACH)
- ACH Debit: You authorize the Department’s bank to withdraw the amount you owe from your bank account on the date you select.
- ACH Credit: You authorize your bank to send funds to the Department’s account. You must initiate this payment each time you submit payment.
- E-check: Enter your bank account number and routing information to make a one-time payment. The transaction is free.
- Credit card: Enter your credit card information to make a one-time payment. You can use Visa, MasterCard, American Express or Discover. A 2.5% fee is charged by a non-state vendor for this service.
Late filing penalties and interest
Hopefully, you won't need to worry about this section because you're filing and remitting Washington sales tax on time. However, in the real world, mistakes happen.
If you miss a sales tax filing deadline, file your return as soon as possible. Failure to file returns and remit collected tax on time may result in penalties and interest charges, and the longer you wait to file, the greater the penalty and the greater the interest.
The Washington DOR does not currently offer a timely filing discount for sales tax filers. For more accurate details pertaining to interest, penalties, and fees associated with the charges, refer to the Washington DOR website.
If you miss a Washington sales tax filing deadline due to unavoidable circumstances like weather or an accident, you might be eligible for an extension from the DOR. Be prepared to provide evidence to support your request. Furthermore, if you are considering buying a business, it's crucial to contact the Washington DOR beforehand to check its sales and use tax standing. You will be responsible for any existing tax debts after the purchase is complete.
Getting third-party help with sales tax filing
While you can file directly with the DOR, manual filing can be difficult, especially for larger businesses with many transactions across different districts. Outsourcing to experts like accountants, bookkeepers, or sales tax automation companies is common. They understand Washington sales tax law and can help you navigate its complexities.
Quaderno offers a service to simplify your sales tax compliance. Besides generating detailed tax reports with all necessary data, Quaderno can handle the filing process for you. By connecting to your sales data, Quaderno manages the submission of your sales tax returns to the DOR, ensuring timely and accurate filing. This saves time and provides peace of mind.
For further reading that will help you stay compliant and successful as a remote seller, check out our Business Guide to Sales Tax in Washington.
Sales tax filing in other states
- Arizona Sales Tax Filing Guide
- California Sales Tax Filing Guide
- Colorado Sales Tax Filing Guide
- Florida Sales Tax Filing Guide
- Georgia Sales Tax Filing Guide
- Illinois Sales Tax Filing Guide
- Massachusetts Sales Tax Filing Guide
- New Jersey Sales Tax Filing Guide
- New York Sales Tax Filing Guide
- North Carolina Sales Tax Filing Guide
- Pennsylvania Sales Tax Filing Guide
- Texas Sales Tax Filing Guide
- Virginia Sales Tax Filing Guide
Note: At Quaderno we love providing helpful information and best practices about taxes, but we are not certified tax advisors. For further help, or if you are ever in doubt, please consult a professional tax advisor or the tax authorities.
