HB 1096 Washington House · 2025-2026 Regular Session

Increasing housing options through lot splitting.

HB 1096 requires certain Washington cities, those with minimum density requirements under the Growth Management Act, to establish an administrative process for splitting residential lots. This process allows an existing residential lot to be divided into two, facilitating the creation of new middle housing or single-family homes, often with simultaneous review of a building permit. The lot split can be approved administratively by a planning director, without a public hearing, if specific conditions are met regarding lot size, utilities, and access. The bill aims to increase housing options for homeowners and prospective buyers, with the Department of Commerce providing guidance and grants to cities for implementation.

Issues: ✓ Housing

Bill status signed all 5 stages cleared

Introduction

Dec 2024

Committee Review

Mar 2025

House Passage

Apr 2025

Senate Passage

Apr 2025

Signed into Law

May 2025

Introduced Dec 19, 2024 Signed May 17, 2025

Maddy AI version diff · 4 comparisons

What changed between versions

Engrossed Second Substitute Bill → Second Substitute Passed Legislature · 5 edits

MODERATE

This bill updates the administrative lot splitting process to apply to all cities rather than just those with specific density requirements, while also clarifying that the process must use clear, objective standards without pre-hearing public input. The changes streamline the creation of new lots by combining the lot split with building permit reviews and limit future splits on the newly created lots. Additionally, the bill extends time limits for city actions to match state law and adds an exemption for sole-source aquifer areas on Puget Sound islands.

Scope change

The bill's applicability expanded from cities required to meet minimum density requirements to all cities planning under the Growth Management Act.

SCOPE

Expanded the requirement for administrative lot splitting to apply to all cities planning under the Growth Management Act, rather than only those with specific density mandates.

REQUIREMENT

Mandated that lot split applications be reviewed based on clear and objective development standards, explicitly prohibiting pre-decision public hearings and limiting design review to administrative levels only.

Changed the recording authority for lot split surveys from the county assessor to the county auditor.

TIMELINE

Added a provision limiting the time for local government actions on lot splits to the maximum period allowed by state law, unless extended by mutual agreement.

EXEMPTIONS

Created a specific exemption for areas designated as sole-source aquifers on islands in the Puget Sound, where the lot splitting provisions do not apply.

Second Substitute Bill → Engrossed Second Substitute Bill · 8 edits · Apr 27, 2025

MODERATE

The bill was renamed to reflect its final version and expanded to include new density requirements for cities of various sizes, replacing the previous focus solely on lot splitting. The law now mandates specific minimum unit-per-lot densities and affordable housing commitments for cities with populations over 25,000, while also clarifying rules for smaller cities in urban growth areas. Additionally, the bill removes a funding contingency clause that would have voided the act if money wasn't appropriated by a specific date.

Scope change

The bill's scope expanded from exclusively regulating administrative lot splitting to also imposing mandatory density and affordable housing requirements on cities based on population size and location.

TITLE

The bill title changed from 'Second Substitute' to 'Engrossed Second Substitute,' indicating it has passed its final legislative stage.

SCOPE

The summary of the act was updated to reflect that it amends existing density laws in addition to adding new lot-splitting rules.

FISCAL

Section 3 was removed, eliminating the provision that would have nullified the entire act if funding was not provided by June 30, 2025.

REQUIREMENT

New requirements were added to RCW 36.70A.635 mandating minimum density (e.g., 2-6 units per lot) and affordable housing commitments for cities with populations of 25,000 or more.

Specific rules were added for cities with populations under 25,000 located in large urban growth areas, requiring at least two units per lot.

New exemptions were created for lots containing critical areas, sole-source aquifers, or those near major airports to prevent displacement or infrastructure strain.

New provisions require cities to allow at least six of nine types of middle housing and limit parking requirements for developments near transit stops.

ELIGIBILITY

The lot-splitting eligibility criteria were slightly adjusted to clarify that new lots must meet minimum density requirements and that future splits are permanently prohibited.

Bill → Substitute Bill · 11 edits

MAJOR

The bill was renumbered and transferred to the House Housing committee, with the reading date updated to January 29, 2025. The core policy expanded to allow administrative lot splitting in more cities, including those with agricultural zones, and added new protections for renters facing displacement. The legislation now includes funding for cities to implement the program, specific definitions for newly created lots, and immunity for cities from liability regarding buildability.

Scope change

The bill now applies to cities in residential zones and exclusively nonresidential zones (previously only minimum density zones), and explicitly includes agricultural zones in the list of prohibited zones.

TIMELINE

The reading date was updated from January 13, 2025, to January 29, 2025.

Added specific deadlines for cities to comply with the new requirements based on their comprehensive plan review schedules.

SCOPE

The bill was renumbered from H-0266.1 to H-0904.1 and the sponsor list was updated to reflect committee referral.

ELIGIBILITY

Added a condition that the parent lot must be located in a residential zone and not in an exclusively nonresidential zone, including agricultural zones.

REQUIREMENT

Added a requirement that if a lot split displaces a renter, the applicant must recommend a displacement mitigation strategy, such as relocation assistance.

Added a condition that the lot split survey must include a notation stating that future lot splits are not authorized under this section.

Added a requirement that newly created lots must meet any locally adopted minimum density requirements.

Added a requirement that ordinances adopted to comply with the section are not subject to administrative or judicial appeal.

DEFINITION

Added a new definition for 'newly created lot' and modified the definition of 'parent lot' to clarify the process.

FISCAL

Added a requirement for the Department of Commerce to provide grants to cities to cover the full cost of implementing the lot splitting program.

ENFORCEMENT

Added immunity for cities from liability related to approving lot splits, even if the resulting lot is later found to be unbuildable.

Floor votes · Senate Apr 14, 2025 · House Mar 6, 2025

How they voted

45–4

Passed · 2 other

Total votes 51

Apr 14, 2025

D Democratic31

27 Yea 2 Nay 2

87% Yea

R Republican20

18 Yea 2 Nay

90% Yea

Vote distribution

All Yea All Nay Mixed No data

Full legislative history

Actions timeline

Total actions

Key actions

Committee

May 17, 2025

Signed into law

Governor signed.

executive

Apr 27, 2025

Upper · Passed

President signed.

upper

Apr 27, 2025

Lower · Passed

Speaker signed.

lower

Apr 27, 2025

Lower · Passed

Passed final passage; yeas, 94; nays, 4; absent, 0; excused, 0.

lower

Apr 27, 2025

Lower · Passed

House concurred in Senate amendments.

lower

Apr 14, 2025

Upper · Passed

Floor amendment(s) adopted.

upper

Mar 26, 2025

Upper · Passed

HSG - Majority; do pass.

upper

Mar 26, 2025

Upper · Passed

Executive action taken in the Senate Committee on Housing at 10:30 AM.

upper

Mar 21, 2025

Upper · Passed

Executive session scheduled, but no action was taken in the Senate Committee on Housing at 10:30 AM.

upper

Mar 14, 2025

Upper · Passed

Public hearing in the Senate Committee on Housing at 10:30 AM.

upper

Mar 6, 2025

Lower · Passed

Floor amendment(s) adopted.

lower

Feb 21, 2025

Committee

Referred to Rules 2 Review.

lower

Feb 20, 2025

Lower · Passed

Executive action taken in the House Committee on Appropriations at 4:00 PM.

lower

Feb 12, 2025

Lower · Passed

Public hearing in the House Committee on Appropriations at 4:00 PM.

lower

Jan 29, 2025

Committee

Referred to Appropriations.

lower

Jan 27, 2025

Lower · Passed

Minority; without recommendation.

lower

Jan 27, 2025

Lower · Passed

Executive action taken in the House Committee on Housing at 1:30 PM.

lower

Jan 13, 2025

Lower · Passed

Public hearing in the House Committee on Housing at 1:30 PM.

lower

1 primary · 21 co-sponsors