Registration Requirements in Washington
Depending on your business you may be required to register with the Washington Department of Revenue and other various state agencies. The State of Washington has a guide for registering your business, found here.
S-Corporation Income Tax
Washington recognizes the federal S-election, and Washington S corporations are not required to pay tax to the state.
LLC/Partnership Income Tax
LLCs and partnerships are not required to pay income tax to Washington.
Business and Occupation Tax
The Business and Occupation (B&O) tax is a gross receipts tax. It’s based on the value of products, gross proceeds of sale, or gross income from the business. The tax rate varies by classification. A complete list of classifications and rates can be found here. The form to file a B&O return can be found here.
Individual Income Tax
The state of Washington does not impose a personal income tax.
B&O tax returns are due by January 31st following the close of the tax year.
Late filing penalties are charged as follows.
If your business was formed or is located in another state, but generates income in Washington, it may be subject to Washington taxes. The rules for taxation of multistate businesses, including what constitutes nexus with a state for the purpose of various taxes, are complicated. If you run such a business, you should consult with a tax professional.