WA SB5633

Repeals and replaces the existing land subdivision statutes (RCW 58.17) with a new chapter 58.17A RCW, comprehensively updating laws originally enacted in 1969 that have not been modernized since adoption of the Growth Management Act

Eliminates the distinction between short plats and subdivisions by making all plat approvals administrative rather than requiring public hearings, except for subdivisions outside urban growth areas that are not exempt from environmental review

Requires cities to adopt procedures for "unit lot subdivisions" by June 30, 2026, allowing multifamily development projects to subdivide parent lots into individual unit lots with specific disclosure requirements for purchasers

Authorizes cities meeting minimum density requirements to allow "minor plats" that administratively divide one residential lot into two lots without full subdivision requirements

Establishes 170-day maximum timeline for plat decisions requiring public notice and hearing, with provisions for permit fee refunds (10-20%) when jurisdictions miss deadlines, effective July 1, 2026 for most jurisdictions