Substitute Senate Bill 5798 amends multiple property tax provisions in state law. It revises the senior citizen/disabled/veteran property tax exemption statutes (amending RCW 84.36.381 and 84.36.383) by changing eligibility details, ownership and residence definitions, the calculation of combined disposable income, documentation procedures, valuation rules for long‑term qualified exemption amounts, and by establishing three income‑threshold tiers that determine the amount of regular and state property tax exemption. The bill also adds definitions (for example, “residence,” “accessory dwelling unit,” “combined disposable income,” “cotenant,” and a $7,500 standard deduction per claimant plus $7,500 for a spouse or domestic partner) and ties the numeric income thresholds to county median household income with a schedule for increases through 2026 and different percentage floors beginning in 2027, with adjustments every three years as provided in RCW 84.36.385(8). The bill makes procedural and administrative changes to tax billing, collection, and delinquency processes (amending RCW 84.56.020 and related sections). It requires tax statements to identify the state property tax as the “state school levy” and sets distribution, due date, and delinquency rules (due dates April 30 and October 31). It revises interest and penalty rules for delinquent property taxes, including a reduction of interest to 9% per annum beginning January 1, 2023 for residential parcels of four or fewer units, a pause on penalties during 2022 and specific penalty schedules thereafter for certain property types, authorization for payment agreements and partial payments, electronic billing options, mandatory delinquency notices with referral information, a requirement to notify homeownership resource centers after two years of delinquency, and a potential waiver of interest and penalties for income‑qualified homeowners subject to foreclosure after about three years. The act also sets the statewide property tax levy rate at $2.095 per $1,000 for taxes levied for collection in 2026 and returns levy limitations to chapter 84.55 RCW beginning with taxes levied for collection in 2027. It amends RCW 84.36.630 to exempt from state‑purpose property taxes all personal‑property machinery and equipment owned by a farmer and used exclusively in producing agricultural products for the calendar year, with claims filed on department forms with the county assessor. Several excerpts and definitions in the provided text are incomplete (for example, the full definition list for “disposable income,” some referenced sections such as parts of Secs. 101–103, and the remainder of certain amended sections are truncated), so the summary is limited to the provisions and schedules that appear in the extracted material.

If enacted, many older, disabled, and some veteran homeowners will likely pay much less in property tax because the bill ties new, income-based exemption tiers to county median incomes and creates larger exempt amounts of a residence’s assessed value for lower-income tiers; low-income claimants can be fully exempt from certain state and local taxes if local ordinances allow. Practically, qualifying households will need to calculate “combined disposable income” using a new standard deduction ($7,500 plus $7,500 for a spouse/partner) or itemize certain medical and care expenses, and county assessors may require income documentation by May 31; for some long‑qualified seniors the law can freeze the valuation used to compute the exemption, which can materially reduce their tax bills. The provided text leaves the complete technical definition of disposable income and some other implementation details incomplete, so exact benefit amounts and eligibility edges are unclear. County treasurers and assessors are the most affected government actors: they must update tax statements (including labeling the state school levy), implement new income-verification and valuation rules, adjust billing and collection practices to reflect different interest and penalty schedules (lower interest for small residential parcels and a 2022 penalty suspension, with penalties reinstated in 2023 for certain property types), offer payment plans and partial-payment options, notify and refer delinquents to housing resource centers, and apply waivers for income-qualified taxpayers facing foreclosure. Farmers who use machinery and equipment exclusively for production can avoid state property tax on that equipment if they file the prescribed claim. The bill also fixes the statewide property tax levy rate for 2026 at $2.095 per $1,000 and then returns levy limits to existing rules in 2027; the full fiscal impact on county and state revenues cannot be determined from the excerpted text.