Washington State Solar Incentives 2026: Net Metering, Tax Exemptions & Savings

Washington State offers a compelling combination of solar incentives — including a full sales tax exemption on solar equipment, retail-rate net metering protected by state statute, and utility-specific rebate programs — but it comes with an important asterisk: Washington has some of the lowest electricity rates in the nation, thanks to abundant hydropower. Understanding that trade-off is the most important thing a Washington homeowner can do before going solar.

This guide covers every incentive available to Washington solar buyers in 2026, the real payback math in Seattle vs. Spokane, and how to decide whether solar makes sense for your specific home, utility, and location.

Washington Solar Market Overview

Washington is the 11th-largest solar market in the U.S. by installed capacity — a ranking that belies the state's strong policy environment. The hesitancy has traditionally been twofold: overcast skies in Western Washington and low electricity rates statewide. Both concerns are more nuanced than they appear.

Solar resource by region:

• Western Washington (Seattle, Tacoma, Olympia, Bellingham): 3.8–4.2 peak sun hours per day. Not Arizona, but comparable to the UK (a global solar leader) and sufficient for a positive ROI — just with a longer payback than sunnier states.
• Eastern Washington (Spokane, Tri-Cities, Yakima, Walla Walla): 4.7–5.3 peak sun hours per day. This is solidly in the mid-tier of U.S. solar performance — similar to North Carolina and better than most of the Midwest.
• Southern WA / Columbia River corridor: 4.9–5.1 peak sun hours per day — the state's sunniest region.

Electricity rates: Washington's average residential rate is approximately $0.10–$0.11/kWh — roughly 30% below the national average of $0.16/kWh. This means solar panels save less money per kWh generated than they would in Massachusetts or California. However, Washington electricity rates have been rising at 4–5% annually as utilities upgrade aging infrastructure. At that rate, your $0.10/kWh rate becomes $0.15/kWh within 10–11 years — which significantly improves the long-term ROI of a solar investment made today.

---

1. Federal 30% Investment Tax Credit (ITC)

The largest single incentive available to Washington homeowners is the federal ITC, which provides a 30% tax credit on the full installed cost of a solar system (including labor, wiring, and permitting). Washington residents are eligible for the same federal credit as any U.S. homeowner.

Washington ITC examples:

System Size	Typical Installed Cost	30% ITC Value	Net Cost After ITC
7 kW	$21,000	$6,300	$14,700
9 kW	$26,500	$7,950	$18,550
11 kW	$32,000	$9,600	$22,400
13 kW	$38,000	$11,400	$26,600

The ITC is a dollar-for-dollar credit against your federal income tax liability — not a deduction. If your tax liability in the year of installation is less than the full credit amount, you can carry the unused portion forward to future tax years. The 30% rate applies through December 31, 2032.

For complete mechanics and filing instructions, see our Federal Solar Tax Credit Guide.

Battery storage: Adding a battery system (Tesla Powerwall, Enphase IQ 5P, etc.) qualifies for the same 30% ITC. In Washington — where grid outages during winter storms and wildfires are common — battery storage paired with solar is an increasingly popular choice, especially east of the Cascades.

---

2. Washington Sales Tax Exemption

Washington imposes a combined state and local sales tax rate of 10.1% to 10.4% depending on the county (among the highest in the nation since Washington has no state income tax). Fortunately, solar energy systems are fully exempt from Washington state and local sales tax under RCW 82.08.962 and RCW 82.12.962.

This exemption covers:

• Solar panels (photovoltaic modules)
• Inverters
• Racking and mounting hardware
• Battery storage systems
• Electrical components and wiring directly related to the solar system

What the exemption saves you:

System Cost (Before Tax)	Tax Rate (King County)	Exemption Value
$21,000	10.25%	$2,153
$26,500	10.25%	$2,716
$32,000	10.25%	$3,280
$38,000	10.25%	$3,895

This is a meaningful incentive — particularly in Seattle, Bellevue, and Kirkland where the combined tax rate exceeds 10%. Make sure your solar installer applies the exemption at time of sale (it is the seller's responsibility to claim the exemption on the sales tax return). If an installer quotes you a price that includes sales tax, flag it — you should not be paying sales tax on solar equipment.

---

3. Washington Net Metering

Net metering in Washington is governed by RCW 80.60 and is a customer right protected by state statute — meaning utilities cannot eliminate or water down net metering without legislative action (unlike California, which changed net metering via regulatory order).

How Washington net metering works:

• Credit rate: Retail rate — the same rate you pay for electricity (currently $0.10–$0.13/kWh depending on your utility). This is the most favorable type of net metering: every kWh your solar system exports to the grid offsets one kWh of consumption at full price.
• Billing cycle: Monthly netting — excess production credits accumulate on your bill.
• Annual true-up: At the end of each 12-month period (typically April 1), any remaining net metering credits are zeroed out. You do not receive a cash payment for excess annual generation.
• System size limit: 100 kW for residential (far above any typical home installation).
• Who must offer it: All investor-owned utilities (IOUs) in Washington — including Puget Sound Energy, Avista, Pacific Power/PacifiCorp, and Peninsula Light — are required to offer net metering. Publicly owned utilities (Seattle City Light, Tacoma Power, Snohomish County PUD) are encouraged but not mandated under RCW 80.60; in practice, most large public utilities offer equivalent programs.

Important implication: Unlike California's NEM 3.0 (which cut export rates to $0.03–$0.08/kWh), Washington's retail-rate net metering means a Washington solar system can export power freely without penalty. Right-size your system to your annual consumption, and the grid handles month-to-month variability at zero cost.

---

4. Utility-Specific Programs

Puget Sound Energy (PSE) — Western Washington

PSE serves about 1.1 million electric customers in King, Pierce, Kittitas, Thurston, and other counties. PSE offers:

• Net metering: Retail rate, monthly billing, April true-up.
• Green Power program: PSE's solar incentive history includes a now-expired production incentive; currently no standalone PSE rebate for rooftop solar exists. Monitor PSE's website for future incentive announcements.
• EV + Solar synergy: PSE's EV-specific rate plans (off-peak charging discount) pair well with solar production during the day. See our Solar Panels and EV Charging Guide.
• Battery storage: No PSE-specific battery rebate, but battery storage reduces your demand on PSE's grid during outage events (Western WA sees roughly 1–3 multi-hour outages per year in urban areas; more in rural/suburban areas subject to tree-fall).

Seattle City Light (SCL) — City of Seattle

Seattle City Light is a municipal utility with some of the lowest electricity rates in the country ($0.097–$0.13/kWh by tier in 2026). SCL offers:

• Net metering: Retail-rate monthly netting with annual true-up. Credits expire April 30.
• Solar incentive rebate: SCL periodically offers direct installation rebates. Check SCL's website for current program availability — programs have been offered in past years ($100–$500/kW).
• Interconnection: SCL's interconnection process typically takes 4–8 weeks for residential systems ≤12 kW. Simple systems (under 6 kW, single-phase) can often qualify for a streamlined "Level 1" interconnection review.

Avista Utilities — Eastern Washington (Spokane)

Avista serves eastern Washington, including Spokane, Spokane Valley, Cheney, Pullman, and Lewiston (ID). Rates: $0.09–$0.12/kWh. Avista offers:

• Net metering: Retail rate, monthly billing, April true-up under Washington law.
• Solar programs: Avista has participated in Washington's utility renewable energy programs. Monitor Avista's website for current rebate availability.
• Eastern WA advantage: With 4.7–5.2 peak sun hours per day in Spokane, Avista customers get significantly better solar production than their Seattle counterparts — partially offsetting the lower electricity rates.

Snohomish County PUD (SnoPUD) — Snohomish and Island Counties

SnoPUD is a public utility serving Everett, Lynnwood, and surrounding areas. SnoPUD offers:

• Net metering: Monthly netting at retail rates; annual true-up April 1.
• Rebate program: SnoPUD's Green Power program has historically offered production incentives. Check the current program status at SnoPUD's website — programs change based on funding.

Clark Public Utilities — Southwest Washington (Vancouver)

Clark PUD serves the Vancouver/Portland metro area on the Washington side. Rates are among the lowest in the state ($0.07–$0.09/kWh). Net metering at retail rate. Clark PUD has offered periodic solar rebates — verify current program status. The Clark County area benefits from more sun than Seattle (4.2–4.5 peak sun hours) due to drier weather in the Columbia River Gorge.

---

5. Property Tax Exemption

Washington does not offer a blanket property tax exemption for residential solar installations. Unlike California, New York, and New Jersey, Washington has not enacted a residential solar property tax exemption at the state level.

However, some Washington counties and municipalities have their own assessment practices. In King County, solar installations generally do not cause a significant reassessment increase for modest residential systems. Verify with your county assessor before installation if property tax impact is a concern.

This is one area where Washington lags its peer states. Advocacy groups are actively pushing for a statewide residential solar property tax exemption — watch for legislative changes in future sessions.

---

6. Low-Income and Rural Programs

USDA Rural Energy for America Program (REAP)

Washington farmers, agricultural producers, and rural small businesses can receive REAP grants of up to 50% of system cost (up to $1 million) or guaranteed loans for solar installations. This is among the most generous federal programs available. Inland Washington — Yakima Valley, Wenatchee, Spokane County agricultural areas — has a large base of eligible REAP applicants.

Contact the Washington State USDA Rural Development office (Spokane) to apply. REAP applications are accepted quarterly.

Weatherization Assistance Program (WAP)

The Washington State Department of Commerce administers WAP for income-eligible households. While WAP focuses on insulation, HVAC, and weatherization rather than solar, WAP improvements reduce energy consumption, which improves the economics of solar (smaller system needed for the same bill savings). WAP is administered through local Community Action Agencies.

Washington Low Income Home Energy Assistance Program (LIHEAP)

LIHEAP provides heating/cooling cost assistance for income-eligible households. Not a solar incentive, but often paired with weatherization to make low-income homes solar-ready.

Community Solar

Washington has an emerging community solar market. For renters, condo owners, or homeowners with shaded roofs who cannot install rooftop solar, community solar subscriptions allow participation in solar without panels on your own property. See our Community Solar Guide.

---

Full Incentive Stack: Two Washington Examples

Example 1: Seattle (King County), 9 kW System, PSE Customer

Item	Value
Installed cost	$26,500
Federal 30% ITC	−$7,950
WA Sales Tax Exemption (10.25%)	−$2,716
Net Cost After Incentives	$15,834
Annual production (3.9 ph/day × 9 kW × 0.82 system efficiency × 365)	~10,500 kWh
Annual savings at $0.11/kWh (net metering, retail rate)	~$1,155/year
Year 5 savings (4% rate inflation)	~$1,275/year
Year 10 savings	~$1,555/year
Simple payback (before rate inflation)	~13.7 years
Payback with 4% rate inflation	~11 years
Lifetime savings (25 years, 4% rate escalation)	~$40,500
25-year ROI on net cost	~156%

A 13-year payback is longer than Arizona or New Jersey — but the system is still firmly cash-flow positive over its 25-year life. If PSE's rates continue rising at 4–5% annually (consistent with the past decade), the payback improves materially.

Example 2: Spokane (Spokane County), 8 kW System, Avista Customer

Item	Value
Installed cost	$23,500
Federal 30% ITC	−$7,050
WA Sales Tax Exemption (8.9% Spokane County)	−$2,092
Net Cost After Incentives	$14,358
Annual production (5.0 ph/day × 8 kW × 0.82 × 365)	~11,980 kWh
Annual savings at $0.10/kWh	~$1,198/year
Year 5 savings (4% rate inflation)	~$1,459/year
Year 10 savings	~$1,776/year
Simple payback (before rate inflation)	~12 years
Payback with rate inflation	~9.8 years
Lifetime savings (25 years, 4% rate escalation)	~$48,200
25-year ROI on net cost	~236%

Eastern Washington's stronger sun resource (5.0 vs. 3.9 peak sun hours) produces about 14% more energy per installed kilowatt than Seattle. Combined with a slightly lower tax rate and a smaller system cost, Spokane's payback is approximately 1–3 years shorter than Seattle.

---

Washington vs. Neighboring States

State	ITC	Sales Tax Exemption	Property Tax Exemption	Net Metering	Avg. Electricity Rate	State-Level Incentive
Washington	30%	Full (10%+)	None	Retail rate (statutory)	$0.10–$0.11	None
Oregon	30%	Partial (some categories)	Statutory in major counties	Retail rate	$0.12–$0.13	None currently
California	30%	Full (7.25%+)	Full (10 years)	Export at ~$0.03–$0.08	$0.25–$0.45	SGIP battery rebate
Idaho	30%	Partial	None	Retail rate	$0.09	None
Colorado	30%	Full	Full	Retail rate	$0.14	Xcel Solar*Rewards

Washington's retail-rate net metering (protected by statute) and full sales tax exemption make it a better policy environment than California's NEM 3.0 cut, despite California's higher utility rates. The key differentiator is Washington's low base electricity rate — which is where most of Washington's longer payback comes from, not from the incentive structure.

---

Is Solar Worth It in Washington State?

The honest answer: yes, but with more patience required than in high-rate states.

Solar in Washington delivers a positive lifetime return in virtually every scenario analyzed. The system of retail-rate net metering means your excess solar production is fully valued. The sales tax exemption reduces system cost by $2,000–$4,000. The federal ITC cuts cost by 30%. Rates are rising. A well-sized system purchased in 2026 will be producing electricity for free by 2034–2038 (Spokane) or 2037–2042 (Seattle) — and continue generating savings for another 10–15 years beyond that.

The solar buyer who gets the best results in Washington:

• Owns their home (loan or cash purchase — leases limit incentive stacking)
• Has a south or west-facing roof with minimal shading
• Is east of the Cascades (more sun = faster payback) OR has above-average electricity consumption (more kWh consumed = more kWh saved)
• Combines solar with battery storage for grid outage protection and TOU optimization
• Evaluates multiple quotes — get at least three from local WA-licensed installers

For help sizing your system, see our How Many Solar Panels Do I Need Calculator. For the complete financial model, use our Solar Payback Period Calculator.

---

Steps to Go Solar in Washington in 2026

1. Check your roof: South, southwest, or west-facing unshaded roof area is ideal. Minimum recommended: 300 sq ft for a 6 kW system.
2. Review 12 months of utility bills: Identify your annual kWh consumption. This is the primary input for system sizing.
3. Get three quotes: Washington has a mature installer market. Compare on $/watt installed, equipment quality (tier-1 panels vs. budget), warranty terms, and timeline.
4. Verify net metering policy with your specific utility: Confirm your utility offers retail-rate net metering and ask about the annual true-up date.
5. Confirm sales tax exemption is applied: Your quote should not include Washington state or county sales tax on solar equipment.
6. Apply for building permit: Washington solar installations require a building permit and final inspection. Your installer handles this; expect 2–6 weeks depending on your county.
7. Utility interconnection: After installation and inspection, your utility must complete an interconnection agreement before the system goes live. Typical timeline: 2–6 weeks.
8. Claim the 30% ITC: File IRS Form 5695 (Residential Energy Credits) with your federal taxes in the tax year the system is placed in service.

---

Key Takeaways

Washington State's solar incentive package — full sales tax exemption, retail-rate net metering protected by statute, and the federal 30% ITC — creates a solid foundation for residential solar investment. The state's low electricity rates extend payback periods compared to high-rate states like California or Massachusetts, but rising utility costs, a 25-year system life, and the absence of property tax increases from solar mean Washington homeowners can expect a strong positive lifetime return. Eastern Washington in particular, with 5.0+ peak sun hours per day, delivers payback periods of 9–12 years — competitive with national averages.