Modifying business and occupation tax surcharges, rates, and the advanced computing surcharge cap, clarifying the business and occupation tax deduction for certain investments, and creating a temporary business and occupation tax surcharge on large companies.

Added a new section requiring the department to consult with a business advisory council and stakeholder taxpayers to recommend statutory and administrative changes that simplify tax compliance.

Modified the surcharge on high-grossing businesses to add a specific exemption for income from the wholesale or retail sale of petroleum products by out-of-state owners processed by affiliated Washington processors.

Changed the expiration date of the surcharge on large companies from December 31, 2030, to December 31, 2029.

Updated the effective date for several sections (114, 201, 301, 401, 402) to January 1, 2026, to include the new compliance simplification requirement.

Added a provision requiring that if computer science or engineering enrollment demand exceeds available spots at state universities by 100 applicants, the surcharge revenues must automatically fund those additional enrollments.

Reorganized the definition of 'family investment vehicle' to explicitly allow nonprofit organizations alongside family members and streamlined the list of included investment types.

Increased the maximum annual cap on the advanced computing surcharge from $9 million to $75 million.

Adjusted B&O tax rates for businesses based on revenue thresholds, adding a new 2.1% rate for businesses with gross income of $5 million or more.

Added retirement accounts and family investment vehicles as eligible entities for the investment tax deduction.

Added new definitions for 'family investment vehicle' to include estates, family trusts, and specific education savings accounts.

Increased the advanced computing surcharge rate for the period starting January 1, 2026, from 5% to 7.5%.

Added an exemption for the large company surcharge for income derived from wholesale or retail sales of petroleum products processed by affiliated out-of-state processors.