Seattle Solar Permit Guide
Seattle City Light (SCL) territory · King County
Overview
GridPermit collects Washington residential solar and permitting facts directly from official sources (city, county, and state government sites, utilities, and public utilities commissions) and shows only what we can verify, with a confidence score and a link to where it came from. Nothing here is estimated or inferred beyond what's stated below. See our methodology for the rules this page follows.
Battery/solar incentive program on record
No battery/storage incentive program is on record for this locality.
Permit fees
- Electrical permit fee, systems up to 12kW: amount not verified (1.5x the published 'base fee' (SBCC Chapter 22.900B) plus the 'administrative fee' (Chapter 22.900D, Table D-15))
Per SDCI Tip #420. Exact dollar figures are published annually in the Permit Fee Subtitle on the Seattle Building Code Council (SBCC) website and were not independently pulled into a flat dollar amount this session.
- Electrical permit fee, systems over 12kW: amount not verified (3x the published 'base fee' (SBCC Chapter 22.900B) plus the 'administrative fee' (Chapter 22.900D, Table D-15))
Per SDCI Tip #420.
Rebates
Not yet verified.
Utility and generation supplier
Utility
Seattle City Light (SCL)
Generation supplier
Seattle City Light (SCL) (utility)
SCL is itself the municipal generation and distribution utility for Seattle; no separate generation supplier or CCA applies.
Interconnection
https://www.seattle.gov/city-light
Per SDCI Tip #420 (jointly developed with SCL, updated 2025-07-14): customer-owned, grid-connected systems of 100kW or less qualify for SCL's Net Metering program (subject to inspection); some arrays up to 250kW qualify under a separate 'Large Solar Program.' An Interconnection Application and Agreement is required, conditional on final approval of the electrical permit. With net metering, excess electricity generated during a billing period is credited back to the customer (true retail-rate net metering, described as spinning the meter backwards).
Required documents
- Electrical permit — for systems up to 12kW, an Over-The-Counter (OTC) permit requiring a one-line electrical diagram and catalogue cuts (required when: always, for all solar electric systems)
- Electrical permit plan review submission (fuller review, not the OTC path) (required when: systems larger than 12kW)
- Building permit (required when: when the rooftop solar installation does NOT meet ALL of 9 specific exemption criteria (single-family rooftop, engineered mounting system, lightweight roof material, panels ≤18in above roof surface and not exceeding the ridge height, ≤5 lb/sq ft dead load, load spread across framing sections not exceeding 50 lb per section, attachment per manufacturer spec, proper weatherproofing, and compliance with land use/fire code) — OR for ground-mounted systems, commercial/industrial systems, or building alterations valued over $6,000)
- Interconnection Application and Agreement with Seattle City Light (required when: always, for grid-connected systems)
- Plumbing permit (issued by Seattle/King County Public Health) (required when: solar hot water systems)
Inspection steps
- An electrical inspection is required after installation for all solar electric systems
- Systems qualifying for SCL's Net Metering program are subject to inspection
- Detailed Seattle Fire Code roof-access-pathway rules apply unless the structure has automatic fire sprinklers, a roof slope ≤2:12, a solar array ≤33% of roof area and ≤1,000 sq ft with an 18in pathway maintained, or is a detached non-habitable structure
Eligibility constraints
- Property types: residential
- Max system size (AC): 100 kW
- Max system size (DC): Not yet verified.
- Max thermal capacity: Not yet verified.
- Program/pathway: Building-permit-exempt path for rooftop single-family systems meeting 9 specific criteria; Over-The-Counter electrical permit for systems ≤12kW
- Other conditions:
- SCL's standard Net Metering program covers systems up to 100kW; some arrays up to 250kW qualify under a separate Large Solar Program
- Rapid Shutdown-compliant systems (per Seattle Electrical Code Section 690.12) may have certain Fire Code marking/DC-conductor-location requirements waived
- RCW 36.70A.813 (statewide) requires cities/counties to allow buildings to exceed roof height limits by at least 48 inches to accommodate solar panels
Official contacts
- SDCI (permits/electrical technical support), phone: 206-684-8600, official website
- Seattle City Light Energy Advisor Line, phone: 206-684-3800, email: SCLEnergyAdvisor@seattle.gov
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Sources
- Seattle Permits Tip #420 — Solar Energy Systems and Solar-Ready Roofs for Residential Buildings (Updated July 14, 2025), Seattle Department of Construction and Inspections (SDCI) and Seattle City Light (SCL) (government). Accessed 2026-08-13.
Frequently Asked Questions
What utility serves solar customers in Seattle, Washington?
Seattle City Light (SCL) is the interconnection and distribution utility for Seattle. The default electricity generation supplier is Seattle City Light (SCL), a utility, separate from Seattle City Light (SCL).
What documents are required for a solar permit in Seattle?
Commonly required documents include: Electrical permit — for systems up to 12kW, an Over-The-Counter (OTC) permit requiring a one-line electrical diagram and catalogue cuts; Electrical permit plan review submission (fuller review, not the OTC path); Building permit; Interconnection Application and Agreement with Seattle City Light; Plumbing permit (issued by Seattle/King County Public Health).
Who do I contact about solar permits in Seattle?
SDCI (permits/electrical technical support), phone 206-684-8600.