States
Washington and the Streamlined Sales Tax program
Simplify Sales Tax. Last updated 2026-08-21. Sources last verified 2026-08-21.
Washington is a full member of the Streamlined Sales Tax program and has been since July 1, 2008, so if you register through the Streamlined Sales Tax Registration System (SSTRS) you file there under the program’s uniform rules. Motor vehicle sales, auto towing, and qualifying florists are sourced under special rules here, so how a product line is classified decides where its sales are sourced, and that’s setup work rather than a rate lookup.
Is Washington in the Streamlined Sales Tax program?
Yes, as a full member, effective July 1, 2008. Washington is one of all 24 member states in the Streamlined Sales Tax program.
Table: Washington in the Streamlined Sales Tax program. Checked August 21, 2026.
| Item | Washington |
|---|---|
| Membership status | Full member |
| Participating since | July 1, 2008 |
| Tax authority | Washington State Department of Revenue |
| Local tax sourcing | Destination based, so a sale is taxed at the location where the customer receives the merchandise or the service |
| State’s own SST page | Yes, the Washington Department of Revenue’s Streamlined sales tax page |
| Special sourcing by transaction type | Motor vehicle sales, auto towing, and qualifying florists carry sourcing rules of their own, so where the customer receives the goods or the service is not what settles those sales |
What SST membership changes for a seller collecting tax in Washington
Washington comes with the other member states when you register once, on how to register through the SSTRS. It uses the program’s shared definitions and sourcing rules, so one system files there. Selecting it starts an obligation, on what your ongoing obligations are after registering, and whether you qualify to have that work paid for is a separate test, on whether you qualify for free CSP services.
What is specific to Washington
One thing.
Three transaction types are sourced under rules of their own. Washington applies special sourcing rules to motor vehicle sales, auto towing, and qualifying florists. For those lines, the place your customer receives the goods or the service isn’t what settles the sale, so sourcing is a decision you make per product line rather than once for the catalog. Classification is the part to get right: a line pointed at the wrong sourcing rule collects the wrong local amount on every order it touches, and it does that quietly until somebody reconciles it.
None of that goes away because Washington is a member state. The program’s uniform rules reach the ordinary sale here and leave those three carve-outs standing, so a vehicle sale, a tow, or a florist order is still its own determination. Membership doesn’t decide what Washington taxes or at what rate, it doesn’t remove the return, and it reaches none of the states outside the program at all.
Where to register and where to find current rates
Register through the SSTRS and select Washington. Current state and local rates, forms, and dates sit on Washington retail sales tax, the rule for which location a given sale takes is on determine the location of my sale, and the department’s own account of its participation is on its Streamlined sales tax page.
We don’t publish a Washington rate or a filing date here on purpose: a number that changes belongs with the department that changes it.