You must register with the Department of Revenue if you meet any of the following conditions:
- Your business is required to collect sales tax.
- Your gross income is $12,000 per year or more.
- Your business is required to pay taxes or fees to the Department of Revenue.
- You are a buyer or processor of specialty wood products.
To register your business with the Department of Revenue and other state agencies, file a Business License Application.
Once registered, you will receive a business license and Unified Business Identifier (UBI) number from the Business Licensing Service. You will also receive a letter from the Department of Revenue with your UBI/tax registration number and filing frequency. Check out our New business tax basics booklet for an overview of Washington's business taxes and reporting requirements.
Register and pay back taxes
If you have been doing business in Washington and are not registered with the Department of Revenue, you can come forward voluntarily under the Voluntary Disclosure Program.
If you are buying a business or the assets of a business, you may owe tax on capital assets and consumable supplies.
Use this application to lookup a business. Here you will find UBI numbers, addresses, open and close dates, etc. for all businesses registered in Washington State.