This bill amends the Washington estate tax law by adjusting the applicable exclusion amounts for inflation and establishing a new framework for future adjustments. The bill reenacts and amends RCW 83.100.020, specifying that the applicable exclusion amount will be $1,500,000 for decedents dying before January 1, 2006, and $2,000,000 for those dying between January 1, 2006, and January 1, 2014. It further introduces a series of increasing exclusion amounts for decedents dying from January 1, 2014, through August 1, 2025, with the exclusion amount set to $2,959,000 for estates of decedents dying on or after August 1, 2025. Additionally, the bill mandates annual adjustments to this amount based on the consumer price index starting in 2026.

The bill also clarifies definitions related to the estate tax, including terms such as "decedent," "department," and "taxpayer." It specifies that the consumer price index used for adjustments will be based on the Seattle area and outlines the exclusions and deductions applicable to the Washington taxable estate. Notably, the bill states that RCW 82.32.805 and 82.32.808 do not apply to this act, and it establishes an effective date of August 1, 2025, for the new provisions.