This bill amends existing Washington statutes (including RCW 35.63.280; 35A.63.300; 36.70A.545; and RCW 82.59.010) to require cities and applicable counties to allow an increased density bonus for affordable housing developments on property owned or controlled by a religious organization when specific conditions are met. To qualify, at least 20 percent of units must be set aside for low-income households (defined as households at or below 80 percent of local median family income using HUD data), affordability must be secured so monthly housing costs do not exceed 30 percent of income, and a lease or binding obligation must reserve the affordable units for at least 50 years. Developments must not discriminate on specified protected bases and must comply with the federal Fair Housing Amendments Act. Jurisdictions must adopt implementing policies if asked by a religious organization and may require a greater than 20 percent set-aside; religious organizations or their lessees must pay required fees and mitigation costs, and the rules apply to rehabilitation of existing affordable housing and, in fully planning jurisdictions, require location inside urban growth areas. The measure also revises and adds statutory definitions and procedural rules: it amends definitions in RCW 82.59.010 (including “affordable housing,” “applicant,” and other terms), defines “investment project,” “multifamily housing,” “owner,” “underutilized commercial property,” and “qualifying use,” and clarifies that “initiation of construction” is tied to issuance of a building permit (excluding pre-permit site work). For phased investment projects, initiation of construction applies separately to each phase, and when a property is partly used for qualifying commercial use the applicable tax deferral must be apportioned by construction costs under rules to be adopted by the unspecified department. Missing or unclear items in the provided text include the full, untruncated definition of “initiation of construction,” the identity of the department that will adopt apportionment rules, the exact statutory definitions of “religious organization” (which are referenced but not recited), and any other sections, penalties, effective dates, fiscal impacts, or broader chapter context that may appear elsewhere in the bill.

If enacted, cities and counties would have to allow religious organizations (or entities leasing their property) to build more densely on their land when at least 20 percent of units are reserved for low‑income households and that affordability is legally guaranteed for 50 years. Religious owners or lessees would be responsible for all development fees and mitigation costs, must meet HUD income limits (80% of area median income) and 30% housing‑cost affordability standards, avoid prohibited discrimination, and, where applicable, locate projects inside urban growth areas and coordinate with transit agencies. The change makes it easier for faith groups to create long‑term affordable housing by increasing how many units they can build on a site, and it applies to rehabilitation of existing affordable projects as well. The groups most affected are religious property owners and their lessees, local governments, and housing developers. Religious owners gain a new option to increase housing supply but take on binding 50‑year affordability commitments and upfront costs; cities and counties must adopt implementing policies when asked and may set higher affordability thresholds, increasing local administrative work and policy decisions. Some implementation details are unclear from the provided text—specifically which agency must adopt rules for tax apportionment in mixed‑use cases and the exact statutory definition of “religious organization” and the truncated construction‑start definition—so how tax deferrals and certain administrative processes will work in practice is uncertain.