Solar Panel Cost in Washington (2026)
Moderate incentives Average installed cost: $2.85/watt · Typical payback: 15-19 years
Washington solar cost breakdown
| Metric | Washington |
|---|---|
| Cost per watt (low–avg–high) | $2.55 – $2.85 – $3.20 |
| 8.6 kW system cost (before incentives) | $21,930 – $27,520 |
| Average residential electricity rate | $0.11/kWh |
| Average peak sun hours/day | 3.9 |
| Typical payback period | 15–19 years |
| Federal tax credit (cash/loan, 2026) | Not available (expired 12/31/2025) |
Washington-specific incentives
Washington has some of the cheapest hydroelectric power in the country, which makes solar's dollar payback the longest of any state even though net metering pays the full retail rate. Solar equipment is exempt from state sales tax to help offset the gap.
Quick facts
Frequently asked questions
How much do solar panels cost in Washington?
As of 2026, solar panels in Washington average $2.85 per watt installed, typically ranging $2.55-$3.20/W depending on system size, roof complexity, and equipment tier. A common 8.6 kW residential system runs roughly $21,930-$27,520 before any remaining state incentive.
Is there a state solar tax credit in Washington?
Washington has some of the cheapest hydroelectric power in the country, which makes solar's dollar payback the longest of any state even though net metering pays the full retail rate. Solar equipment is exempt from state sales tax to help offset the gap.
What's the typical payback period for solar in Washington?
Most Washington homeowners see a payback period of 15-19 years based on current electricity rates and remaining incentives, since the federal 30% tax credit no longer applies to cash or loan purchases in 2026.
Does the federal solar tax credit still apply here?
No — the 30% federal Residential Clean Energy Credit (Section 25D) expired for cash and loan purchases on December 31, 2025. It only remains available indirectly through solar leases and PPAs, where the financing company claims a separate commercial credit.
Not financial, tax, or legal advice. Figures on this page are 2026 estimates based on industry aggregator data (EnergySage marketplace medians, SEIA/Wood Mackenzie market insight, and regional installer data) and are provided for general informational and comparison purposes only. Actual pricing, incentive eligibility, and payback periods depend on your specific roof, usage, equipment, and local program rules. Confirm current incentive details at dsireusa.org and consult a licensed tax professional and local installers before making a purchase decision.