House Bill 2502 amends multiple sections of the Revised Code of Washington and creates new sections to change which sales and use tax preferences apply at the state level. The bill’s stated purpose is to improve local government fiscal health by removing certain sales and use tax exemptions and, for other items, limiting exemptions to the state portion of the sales tax. It modifies the statutory definition of "sale at retail" to broaden what counts as taxable sales and services and amends many existing exemption and remittance provisions. The bill expands the list of services and transactions treated as retail sales (including a wide range of labor, installation, repair, cleaning, digital goods installation, lodging, certain professional and personal services, information-technology and advertising services, recreational admissions, temporary staffing, and more) while also identifying specific exclusions. It requires purchasers claiming exemptions to furnish department-prescribed exemption certificates and to retain records; sellers must keep copies. Several existing and new exemptions and remittance programs are changed: exemptions for waste vegetable oil used to make biodiesel for personal use, production equipment and services for motion picture/video businesses, computer equipment used primarily by printers or publishers, and aerospace-related computer hardware/peripherals/software are limited so they do not apply to local sales and use taxes. The bill also continues and modifies a state exemption/remittance program for renewable-energy machinery/equipment and installation labor with specific certification, labor-standard, and remittance percentages (including 50%, 75%, or 100% remittances or exemptions under certain certifications), along with detailed timing, documentation, and recordkeeping rules and an explicit requirement that the Department of Labor and Industries adopt rules and certify projects. The bill creates procedural changes and conditions for data center exemptions and associated use-tax relief: it defines eligible computer data centers and eligible server equipment and power infrastructure, sets application and certificate rules, caps, employment and sustainability certification requirements, limits on issuance and transfer of certificates, and triggers for repayment and penalties (including immediate tax repayment and a possible 10 percent penalty where specified). Many provisions include defined effective windows and expiration dates (for example, renewable-energy provisions expire January 1, 2030; certain data center exemptions expire July 1, 2048, with some related provisions extending to 2053), and the text identifies several cross-referenced RCWs. Some important implementation details are incomplete in the extracted material: the bill repeatedly refers to "the department" without naming it in these excerpts, some amended subsections are cut off, and a few effective or expiration dates shown in the bill header were not provided in the available text.

If enacted, the bill will broaden what counts as a taxable retail sale and remove or limit a number of state sales and use tax exemptions, bringing many services and previously untaxed items into the state tax base while also carving exemptions into narrower, certificate‑driven, and time‑limited forms. In practice that means many businesses that provide IT, advertising, recreation, fitness, event, and other services; purchasers of motion‑picture production equipment; printers and publishers buying computer equipment used primarily in printing; solar and other renewable‑generation developers; data center owners and tenants; and aerospace developers will face new tax charges, new requirements to provide or accept exemption certificates, and recordkeeping and audit risk. Some renewable and solar projects and certain data center and production activities retain partial or conditional relief through remittances or exemptions, but those benefits come with certification, prevailing‑wage/apprenticeship or sustainability requirements, upfront payment then application for remittance, and strict time windows or caps. The groups most affected are businesses that will pay or collect more state tax and the state agencies that must implement the changes: an unnamed revenue department to process certificates and remittances and the Department of Labor and Industries to certify labor standards and workforce agreements. Expect higher compliance costs for sellers and purchasers (collecting and retaining certificates, providing contractor and wage documentation), potential cash‑flow impacts from paying tax up front and waiting for remittance, and the risk of repaying taxes plus penalties if employment, wage, or sustainability conditions for data center certificates are not met. Some important implementation details are not shown here—most notably which department administers remittances in certain sections and the bill’s effective and expiration dates for several provisions—so exact timing and administrative procedures remain unclear.