On March 23, 2023, the Washington Department of Revenue issued an emergency rule-making order. The purpose of the emergency rule was to make the public aware that certain of the Department’s administrative rules concerning remote sellers’ sales and use tax nexus and minimum nexus thresholds for the state’s business and occupation tax may be outdated. Specifically, the Department cautioned that the public should not use Rules 193 (Interstate sales of tangible personal property), 221 (Collection of use tax by retailers and selling agents), and 19401 (Minimum nexus thresholds for apportionable activities and selling activities) “to determine their sales or use tax collection obligations or to determine substantial nexus for apportionable activities and selling activities for periods beginning on or after October 1, 2018.” The Department explained that the rules may be outdated because, Substitute Senate Bill No. 5581 (2019) “clarified the sales tax obligation for remote sellers and when a person is deemed to have substantial nexus for business and occupation (B&O) tax purposes.” Substitute Senate Bill No. 5581 (2019) provides that substantial nexus is established by a nonresident individual or business entity who has more than $100,000 of cumulative gross receipts in Washington in the current or immediately preceding year.