As of October 1, 2018, out-of-state businesses must collect sales or use tax on taxable retail sales if they exceed $100,000 in retail sales or have 200 or more retail transactions sourced to Washington in the current or prior calendar year.
Determination of Sale Date
A business may use its normal accounting method to determine when a sale took place. the date of sale can be based on:
- invoice date;
- date of the product’s shipment;
- date the product was received; or
- date when a business receives payment.
The notice can be viewed on the department’s website at https://dor.wa.gov/get-form-or-publication/publications-subject/tax-topics/sales-tax-threshold-out-state-businesses.
Tax Topics, Washington Department of Revenue, October 11, 2018