Sammamish Zoning & Land Use Guide
Key Zoning Facts
Sammamish Zoning Overview
Sammamish is a city in Washington with approximately 65,892 residents, located in King County on the Sammamish Plateau. The city manages land use and development through its zoning code, administered by the Community Development Department. Sammamish's zoning divides the municipality into districts regulating permitted uses, building heights, lot sizes, setbacks, and density.
Sammamish follows the Washington State Building Code (WAC 51-50/51), which is based on the International Building Code (IBC) and International Residential Code (IRC).
Primary Zoning Districts
Sammamish is predominantly a residential community. The R-1 district requires a minimum lot size of 1 acre for estate-style development. The R-4 district allows approximately 4 units per acre with 9,000 square foot lots. The R-6 district allows 6 units per acre with 7,000 square foot lots. The R-8 district supports 8 units per acre with 4,500 square foot lots. All residential districts have a 35-foot height limit.
Limited commercial activity is served by the NB (Neighborhood Business) and CB (Community Business) districts.
ADU (Accessory Dwelling Unit) Rules
Sammamish allows ADUs (Accessory Dwelling Units). Under Washington state law HB 1337 (2023), cities are required to allow ADUs, with up to 2 ADUs permitted per lot in most areas. This is a state mandate that applies to all Washington cities. Contact the Community Development Department for current requirements including size limits, setbacks, and permitting procedures.
Development Process
Development in Sammamish generally requires obtaining the appropriate permits. The process typically involves:
- Zoning Verification — Confirm that your proposed use is permitted in the applicable zoning district
- Site Plan Review — For commercial and multi-family projects, submit a site plan for review
- Building Permit — Apply for a building permit with construction documents
- Inspections — Schedule required inspections during construction
- Certificate of Occupancy — Obtain final approval before occupying the structure
For projects that do not conform to existing zoning, property owners may need to seek a variance, special exception, or rezoning.
Key Considerations
Before starting any development project in Sammamish, property owners should:
- Verify the zoning classification of their property
- Review setback, height, and lot coverage requirements for their specific district
- Check for any overlay districts or special regulations
- Determine if the property is in a flood zone using FEMA's flood map service
- Confirm whether HOA covenants or deed restrictions apply
- Contact Community Development at (425) 295-0500 for pre-application guidance
Disclaimer: This guide provides general information about zoning in Sammamish and should not be relied upon as legal advice. Zoning codes are subject to change. Always verify current regulations with the City of Sammamish or the municipal code before making development decisions.
Regulatory Layers That Apply in Sammamish
Your property is subject to ALL of these regulatory layers. Each one can impose additional requirements beyond the others.
Federal
- FEMA Flood Zones: Applicable
- View FEMA Flood Map
State — Washington
- Building Code: WA State Building Code (WAC 51-50/51)
- State ADU Override: Yes (WA HB 1337 (2023) requires cities to allow ADUs; 2 ADUs per lot in most areas)
County — King County
- Role: County-level property records, tax assessment, unincorporated area planning
City / Municipal
The city's zoning ordinance, building codes, and local permits form the primary layer of land-use regulation for your property.
Overlay Districts
No overlay districts identified.
Private Restrictions
- HOA / CC&Rs common: Yes
- Check HOA CC&Rs and deed restrictions for additional requirements.
Primary Zoning Districts
- Min Lot
- 1 acre
- Max Height
- 35 ft
- Front Setback
- 30 ft
- Side Setback
- 10 ft
- Rear Setback
- 25 ft
- Min Lot
- 9,000 sq ft
- Max Height
- 35 ft
- Front Setback
- 20 ft
- Side Setback
- 5 ft
- Rear Setback
- 25 ft
- Min Lot
- 7,000 sq ft
- Max Height
- 35 ft
- Front Setback
- 20 ft
- Side Setback
- 5 ft
- Rear Setback
- 20 ft
- Min Lot
- 4,500 sq ft
- Max Height
- 35 ft
- Front Setback
- 15 ft
- Side Setback
- 5 ft
- Rear Setback
- 20 ft
- Min Lot
- Varies
- Max Height
- Varies
- Front Setback
- Varies
- Side Setback
- Varies
- Rear Setback
- Varies
- Min Lot
- Varies
- Max Height
- Varies
- Front Setback
- Varies
- Side Setback
- Varies
- Rear Setback
- Varies
ADU Rules in Sammamish
Permit Costs & Timelines
Permit Costs & Timelines
Specific permit fee schedules for Sammamish are available from the local planning department. Fees vary based on project type, scope, and valuation.
Check Sammamish permit fees →