This bill creates a new "primary residence property tax exemption" in chapter 84.36 RCW that exempts part of a residence's assessed value from the state property tax levy (but not from local district taxes). For taxes levied for collection in 2028 and thereafter the exemption is the greater of $100,000 of assessed value or 60 percent of the county median residential assessed value for the most recent year of data, subject to annual publication, adjustments, and limits; the exemption is applied after existing exemptions in RCW 84.36.379–84.36.389. The bill makes several procedural and administrative changes to implement the exemption: claimants must apply by April 1 of the year before first receiving the exemption and provide specified information and a signed attestation; the department must provide online claiming, publish county median values by August 1, and supply assessors with claimant lists; assessors may cancel or be required to cancel exemptions they determine are not qualified or are indeterminate, with appeals available under RCW 84.48.010 and RCW 84.40.038. Cooperative housing entities must reduce assessed values and pass through tax savings to members, remaindermen or others who would otherwise pay the tax must reduce amounts owed or pay claimants the savings, and county treasurers may collect state property taxes wrongly exempted for up to six prior years with interest (but not penalties). The department may audit administration, adopt rules, and a new administration account is created to distribute funds to counties to help with administration (standard annual distribution: $5.00 times the number of applications processed by the state in the most recent year, with special initial-year provisions and specified certification and distribution deadlines). Legally, this is a new tax-exemption statute combined with procedural and administrative changes and a retroactive tax-recovery mechanism; it does not create a new criminal offense but creates administrative duties, audit and rulemaking authority, and a collections procedure for errors. The act is conditioned to take effect January 1, 2026 only if a specified proposed constitutional amendment (Senate Joint Resolution No. (S-0811/25)) providing for a residential real property tax exemption is approved and ratified by voters; if that amendment is not approved the act is void. Some text and details are missing from the provided extracts: the specific identity of "the department" is not consistently stated, the full adjustment formula if the state levy is expected to exceed the statutory maximum is not shown, portions of several subsections are truncated, and the precise amendment text to RCW 84.48.010 is not included.

If enacted, many homeowners who live in their house as their principal residence could pay less state property tax beginning with taxes collected in 2028 because a portion of a home's assessed value would be exempt from the state levy (the exemption will generally be the larger of $100,000 or 60% of the county median residential assessed value, with limits). Homeowners must apply in advance by April 1, keep the home as their primary residence, and can lose the exemption if an assessor finds they no longer qualify; if the exemption was wrongly received, counties can collect up to six years of state taxes owed plus interest, and cooperatives and remaindermen are required to pass through or repay the tax savings to members or claimants. Counties and statewide agencies will have new work and some payback: county assessors and treasurers get added duties to process, inspect, cancel, and collect taxes and to participate in equalization meetings, while the state must publish county median values and may audit administration. The bill creates a state administration account to reimburse counties a small per-application amount (generally $5 per processed application, with higher estimates for initial years) subject to appropriation and possible prorating, so counties may face net administrative costs if reimbursements or appropriations fall short. The measure only takes effect if a specific constitutional amendment is approved by voters, and some implementation details in the text—like which state department administers the program and the exact method for adjusting the exemption when the state levy approaches its statutory cap—are not specified in the extracted facts.