How to File Washington D.C. Sales Tax Online

Filing your Washington, D.C. sales tax return is simple with the city’s online system. You can file and pay directly through the MyTax.DC.gov portal, as long as your business is registered to collect and remit sales tax. This guide walks you through the step-by-step process of filing online so you can submit returns on time, avoid penalties, and stay compliant with Washington, D.C.’s sales tax rules.

What You Need Before Filing

Before filing your Washington, D.C. sales tax return, make sure you have the following in place:

• Sales Tax Permit / Certificate of Registration – Your Washington, D.C. tax account number, issued when you register with the Office of Tax and Revenue (OTR).
•  MyTax.DC.gov Log-in Details – You’ll need your username, password, and access to the account under which you file sales and use tax.
• Total Sales – The full revenue your business earned during the period (taxable + non-taxable).
• Taxable Sales & Taxable Purchases – Detail of sales subject to tax plus any purchases where you owe use tax.
• Relevant Local/City Data – Although D.C. uses a uniform sales tax rate for most transactions, maintain accurate records of where sales occurred (if you have multiple locations) or if special rates apply to your sales (e.g., parking, liquor, or restaurant meals).
• Bank Account/Routing Info – For payment through the online system (ACH Debit or other electronic method).
• Filing Frequency Schedule – D.C. assigns a frequency (monthly, quarterly, or annual) based on your sales volume. 

Step-by-Step: How to File Washington D.C. Sales Tax Online

The online filing process in Washington, D.C. is quick and straightforward through the MyTax.DC.gov portal. Follow these steps to ensure your return is accurate and properly submitted.

Step 1. Prepare your Ecommerce Sales Tax Data (e.g., Taxes Report from Shopify).

Step 2. Go to the MyTax.DC.gov portal.

Step 3. Enter your account credentials. Log in using your username and password.

Step 4. Check your shared email or phone number for the one-time password (OTP) and input it when prompted.

Step 5. On your dashboard, click on “View Returns.”

Step 6. Click “File Now” next to the filing period you wish to submit.

Step 7. Read the introduction and answer the return information questions. Click Next.

Step 8. Answer the return period information. Click Next.

Step 9. Enter your sales tax information, referencing your Ecommerce Sales Tax Report. Click Next.

Step 10. On the main tax return form, fill out the required fields using the data from your Ecommerce Sales Tax Report. Click Next.

Step 11. Review all data carefully and ensure it matches your Ecommerce Sales Tax Report. Click Next.

Step 12. Choose your preferred payment method, then click Next.

Step 13. Enter your payment account information and other details. Click Next.

Step 14. Re-enter your MyTax.DC.gov password to confirm and authorize submission, then click Submit.

Step 15. Save your return and payment confirmation as proof of successful submission.

Save the confirmation in your preferred location for recordkeeping purposes. Keeping online records using Google Drive is a common option.

Helpful Tip: You can always click “Save Draft” to avoid losing progress during filing in case of interruptions like internet loss or system downtime.

Due Dates

In Washington, D.C., the Office of Tax and Revenue (OTR) assigns filing frequencies based on a business’s total taxable sales volume. The standard due date for filing and paying sales tax is the 20th day of the month following the reporting period. To avoid a delinquency notice, a return must be filed even if no sales were made or no sales or use tax is due. Note: When the due date falls on a weekend or legal holiday, the return is due the next business day.

FREQUENCY	REQUIREMENT	REPORTING PERIOD	DUE DATE
Monthly	Standard for most filers unless specified otherwise	Each calendar month	20th of the following month
Quarterly	Assigned when less frequent filing is permitted	Q1: Jan–Mar Q2: Apr–Jun Q3: Jul–Sep Q4: Oct–Dec	Apr 20, Jul 20, Oct 20, Jan 20
Annual	For very low-volume filers as allowed by OTR	January–December	January 20

Timely Filing Discount

Currently, Washington, D.C. does not offer a vendor allowance or a timely filing discount for Sales and Use Tax returns. All sales tax filings and payments must be submitted by their original due dates to avoid penalties and interest. The Office of Tax and Revenue (OTR) emphasizes that extensions available for income or franchise taxes do not apply to sales and use tax obligations.

Even if you’re unable to pay the full balance due, you must still file the return on time to minimize additional penalties.

Filing Amended Returns

If you discover an error after submitting your sales and use tax return, you can file an amended return through MyTax.DC.gov.

To file an amended return:

1. Log in to your MyTax.DC.gov account.
2. Locate your Sales and Use Tax account from the dashboard.
3. Select File, View, or Amend Returns.
4. Choose the return period you want to correct and click Amend.
5. Update the incorrect fields and submit the amended return electronically.

If the amendment results in an overpayment, you must also submit Form FP-331, Claim for Refund, through the same portal. Both the amended return and refund claim are required for processing.

Refunds

If you overpaid your D.C. sales or use tax, you can request a refund by following these steps: File an amended return reflecting the overpayment. Submit Form FP-331 (Claim for Refund) through MyTax.DC.gov.

Refund requests must be made within three years of the original return’s due date or within two years of payment, whichever is later. 

Refunds are not processed without both documents submitted together.

Filing Zero Returns in Washington D.C.

Even if your business made no sales during the reporting period, you are still required to file a zero return.

To file:

1. Log in to MyTax.DC.gov.
2. Access your Sales and Use Tax account and select the period.
3. Choose “No Payment Needed” when prompted for payment options.
4. Submit the return as usual.

Filing zero returns keeps your account in good standing and prevents unnecessary penalties.

Other Filing Methods in Washington D.C.

If you’re having difficulties filing your Washington D.C. sales tax return online, you can try other options.

• File with TaxHero – Let expert accountants in TaxHero prepare your sales tax returns for you. We’ll take everything off your hands so that you can spend your time more efficiently managing your business.
• Paper Filing Waiver: The only exception to the electronic mandate is if your business has received an official electronic filing waiver from the DC Office of Tax and Revenue (OTR). br_spacer]

Let TaxHero Manage Your Washington D.C. Sales Tax Returns

TaxHero doesn’t just handle your Washington D.C. sales tax return; we manage filings across every state where your business has nexus, ensuring each return is filed accurately and on time at the frequency required.

This means you stay compliant nationwide without having to track multiple rules and deadlines yourself.

Don’t wait until the next deadline, schedule your demo today!