House Bill 1818 makes comprehensive changes to chapter 58.17 RCW governing division of land. It amends definitions and thresholds for subdivisions, short subdivisions, plats, and binding site plans; reenacts and amends RCW 58.17.040 to list specific exemptions; adds new sections for binding site plans and administrative lot splits; and repeals several existing RCW sections. The bill shifts many procedural rules to mandatory administrative review for plats (with specified public notice, a 20-day comment period or 30 days for shorelines, a seven-day applicant response period, and limited public hearing triggers), establishes timelines for review and final plat submittal (including a five-year deadline to record final plats in many cases), allows bonds/security for required improvements, clarifies recording and enforcement duties of county auditors and prosecuting attorneys, and preserves a five-year protection period for recorded plats in specified circumstances. The bill creates a binding site plan procedure that makes lots legal upon recording, requires filing of plans and surveys with county auditors, makes binding site plan conditions enforceable against subsequent purchasers, and makes sale or lease of unrecorded or nonconforming lots a violation subject to injunction. It also authorizes exemptions or special procedures for boundary line adjustments and small-lot divisions for certain uses (personal wireless facilities, electric utility facilities, rural fire district sites) subject to specified limitations. A new section requires cities subject to RCW 36.70A.635 minimum density obligations to adopt ordinances allowing an administrative lot split to create one new residential lot under stated conditions; the lot split is processed administratively based on a lot split survey, is not otherwise subject to subdivision rules, and cities may not reduce dwelling unit capacity below pre-split zoning. Cities, towns, and counties must adopt consistent ordinances by June 30, 2026; the act’s provisions supersede conflicting local rules on July 1, 2026; section 6 expires January 1, 2028; and section 7 takes effect January 1, 2028. Some provisions and cross-references in the extracted text are incomplete or cut off (for example portions of RCW 58.17.035, the full criteria in the new lot-split section, and certain effective/expiration details), so the complete scope and final wording of some requirements and procedural interactions cannot be determined from these excerpts alone.

If enacted, the bill shifts most subdivision review from public hearings to an administrative process with firm notice and comment deadlines, shortens and standardizes review timelines, and requires cities, towns, and counties to adopt new ordinances by mid-2026 to allow administrative lot splits and binding site plans. Local governments will need to create procedures to accept complete applications, mail and post notices, handle 20–30 day comment windows, respond within seven days, and hold hearings only if timely requested; they must also record binding site plans and short plats for those to be legal lots. Developers and property owners are likely to get faster, more predictable approvals, concurrent construction-plan review, and five-year protections based on final plats, while utilities, irrigation districts, WSDOT, and county auditors face tighter deadlines to provide certificates, comments, and to record plats. The groups most affected are local governments (cities, towns, counties) which will incur responsibility and likely staffing or administrative costs to adopt ordinances, run the new administrative review procedures, enforce bonding and recording rules, and defend against enforcement actions or appeals; county auditors and prosecuting attorneys also gain duties for recording and enforcement. Property owners and developers gain quicker, more administrative paths to divide land (including an administrative lot split option in certain cities) but must meet new documentation, survey, access, and utility-availability requirements and may face risks if lots are sold before recording or if local rules or some section interactions (and certain effective/expiration dates and the precise role of the “authorized official”) remain unclear from the available text.