Installed home solar in Washington commonly runs about $2.50 to $3.00 per watt before incentives, so a 7 kW system costs roughly $17,500 to $21,000 (confirm with local quotes). Because Washington power is cheap at about 14.36 cents per kWh and Seattle sun is limited, simple payback usually runs about 16 to 20 years. The federal 25D homeowner credit ended December 31, 2025.
Washington homeowners pay about 14.36 cents per kWh for electricity (EIA retail sales, residential WA, period April 2026), one of the lowest rates in the country thanks to the state’s hydropower. Cheap power is great for your budget, but it makes the payback math on solar tougher, because every kWh your roof makes replaces a cheap kWh from the grid. This page walks the cost per watt, the honest payback in a low-rate, low-sun state, and what changed in 2026, and it pairs with our broader Washington solar guide on net metering and incentives. For net-metering mechanics, see our guide to how net metering credits your solar exports.
A 7 kW rooftop system in Seattle produces about 7,615 kWh a year (NREL PVWatts v8, ZIP 98101), and at Washington’s 14.36 cents per kWh residential rate that is roughly $1,090 of grid power you stop buying each year (EIA, April 2026). That is a modest yearly offset by national standards, because both the local rate and the Seattle sun are low, and that small offset is the whole reason Washington payback runs long.
How much does solar cost in Washington?
Price is quoted in dollars per watt of system size. A typical residential install commonly runs about $2.50 to $3.00 per watt before any incentives. That is a national benchmark, not a Washington filing, so treat the table as a starting point and get itemized local quotes to confirm your own $/W. Your price moves with system size, roof complexity, panel and inverter choice, and the installer.
| System size | Fits a home that uses | Estimated installed cost ($2.50 to $3.00/W) |
|---|---|---|
| 5 kW | Smaller bill, roughly $70 to $120/mo | About $12,500 to $15,000 |
| 7 kW | Average bill, roughly $120 to $200/mo | About $17,500 to $21,000 |
| 10 kW | Larger home or an EV, $200+/mo | About $25,000 to $30,000 |
Cost ranges are a national $/W benchmark for planning, not a guaranteed price. Washington’s older renewable-energy sales and use tax exemption for solar equipment has expired, so plan on paying state and local sales or use tax on your system in 2026 and verify the current rule with the Washington Department of Revenue and DSIRE. Confirm your quote before you budget.
What is the solar payback in Washington?
Payback is cost divided by what you stop paying the utility. Because Washington rates are low, the annual bill offset is small, so payback stretches out even though a system here is priced like anywhere else. The table pairs the cost above with a production-based offset. Production is scaled from the verified Seattle PVWatts figure by system size, then multiplied by the 14.36 cents per kWh rate.
| System size | Estimated annual production | Estimated yearly bill offset | Simple payback |
|---|---|---|---|
| 5 kW | About 5,440 kWh | About $780 | About 16 to 19 years |
| 7 kW | About 7,615 kWh | About $1,090 | About 16 to 19 years |
| 10 kW | About 10,880 kWh | About $1,560 | About 16 to 19 years |
Estimates, not a guarantee. Production is scaled from NREL PVWatts v8 for Seattle (ZIP 98101) and priced at the current EIA Washington rate; exported power is credited under net metering, so your real payback depends on how much you self-consume. Rates, production, and prices vary, so verify your own numbers. For a full breakdown, see the financial case for whether solar panels are worth it.
What moves your payback in 2026
Four things decide where a Washington homeowner lands, and here the honest read is that the state leans on net metering rather than cash incentives:
- Your electric rate. At about 14.36 cents per kWh, Washington power is among the cheapest in the country, so each kWh your roof makes is worth less here than in high-rate states, which is the main reason payback is longer (EIA, April 2026).
- Your production. Seattle’s cloudy climate means lower output than sunnier states, and roof pitch, orientation, and shading swing it further. Estimate yours with NREL’s free PVWatts calculator before you size a system.
- Net metering. Washington utilities credit the power you export at the retail rate under state law (RCW 80.60), and excess generation carries forward as kilowatt-hour credits, which is the single biggest lever on payback here. Caps and true-up terms vary by utility, so verify the current rule with your provider. For the mechanics, see how net metering credits your solar exports.
- No federal credit in 2026. The 30% federal Residential Clean Energy Credit (Section 25D) ended for expenditures made after December 31, 2025, under the One Big Beautiful Bill Act, so a Washington homeowner buying with cash or a loan in 2026 cannot claim it (IRS). See what the federal solar tax credit change means in 2026.
The state side is lean, and that is the honest part. Washington’s older renewable-energy sales and use tax exemption for solar equipment has expired, so it no longer trims your cost, and there is no broad state solar income-tax credit or active statewide cash rebate to count on in 2026. Verify the current status of any program with DSIRE and the Washington Department of Revenue before you build it into your math. What carries the payback here is net metering plus the bill you stop paying, not a stack of state incentives, so the case for solar in Washington is driven by long-term ownership, not a fast return.
See your solar cost and payback for your ZIP code
Prices, net-metering credits, installer availability, and electric rates change by utility and location. Enter your ZIP and we will match you with licensed installers who serve your area so you can compare real quotes.
Free to check. About a minute. No credit pull to check.
Submitted securely and used to match you with licensed installers in your area. Some homeowners may qualify for $0-up-front lease/PPA options where available.
How you pay changes the cost you carry
The sticker price is one thing; how you finance it decides your out-of-pocket and your payback.
| How you pay | Up-front cost | Best when |
|---|---|---|
| Cash | Full system price | You want the shortest payback and the most lifetime savings |
| Solar loan | Little or none, financed over time | You want to own the system with low money down |
| Lease or PPA | $0-up-front where you qualify | You want no out-of-pocket cost and a lower or fixed power price without owning |
A lease or PPA has no up-front cost, but the company owns the panels, terms typically run 20 to 25 years and may include an annual escalator, and total payments can exceed a cash purchase. No 2026 Washington homeowner gets the federal residential credit, since that credit ended after December 31, 2025. Whichever path you pick, it helps to know the right questions to ask a solar installer before you sign, and how much you can realistically cut with smart home energy savings alongside solar. When you are ready, start your free ZIP-based match to compare local quotes.
Frequently asked questions
How much does solar cost in Washington?
Installed home solar commonly runs about $2.50 to $3.00 per watt before incentives, so a 5 kW system is roughly $12,500 to $15,000, a 7 kW system is about $17,500 to $21,000, and a 10 kW system is about $25,000 to $30,000. Those are national planning benchmarks, not a Washington price filing, so get itemized local quotes to confirm your own dollars per watt. Washington’s older solar sales-tax exemption has expired, so budget for state and local sales or use tax on the equipment.
What is the payback on solar in Washington?
At the state’s low 14.36 cents per kWh rate, a system offsets only a modest annual bill, so simple payback usually runs about 16 to 20 years before years of largely free production follow. A 7 kW system in Seattle produces about 7,615 kWh a year (NREL PVWatts v8), roughly $1,090 of grid power at today’s rate (EIA, April 2026). Cheap hydropower and limited Seattle sun both stretch the payback, so Washington solar is a long-term ownership play, not a fast return.
Is there a Washington solar rebate or state tax credit in 2026?
Not a broad one to count on. Washington’s former renewable-energy sales and use tax exemption for solar equipment has expired, and the state has no broad personal income tax and no active statewide cash rebate or income-tax credit for residential solar in 2026. Verify the current status of any program with DSIRE and the Washington Department of Revenue, because listings change. The main financial benefit that remains is net metering plus the bill you stop paying.
Does a Washington homeowner qualify for the federal solar tax credit in 2026?
Not as a homeowner buying in 2026. The 30% federal Residential Clean Energy Credit (Section 25D) ended for expenditures made after December 31, 2025, under the One Big Beautiful Bill Act, so a cash or loan buyer cannot claim it. A separate commercial credit (Section 48E) can apply to leased and PPA systems, but the business that owns the system claims it, not the homeowner.
Does net metering improve the payback in Washington?
Yes, it is the biggest lever here. Washington utilities credit the power you export at the retail rate under state law (RCW 80.60), and excess generation carries forward as kilowatt-hour credits. Because state cash incentives are lean, that retail-rate credit does most of the work on payback. Caps, true-up dates, and terms vary by utility, so confirm your provider’s current net-metering rule before you size a system.
Reviewed by the MySolarFY team. Cost and payback figures are estimates built from NREL PVWatts v8 production (Seattle, ZIP 98101) and the EIA Washington residential rate, with incentive facts verified against DSIRE and IRS sources as of August 2026; prices, production, tariffs, and programs change, so confirm current numbers with local installer quotes and each source before you decide. MySolarFY does not provide tax or financial advice; consult a licensed professional about your own situation. Learn more about the MySolarFY team and how we work.
MySolarFY is a free service that matches homeowners with licensed solar installers. We are not an installer, financing company, or government program. “No up-front cost” refers to qualifying lease or PPA financing, where eligible homeowners may have no out-of-pocket cost at installation. Lease and PPA terms typically run 20 to 25 years, may include an annual price escalator, and total payments may exceed the cost of a cash purchase. Homeowners do not get the federal residential credit that ended after December 31, 2025. Solar panels are not free and monthly payments apply. Cost, savings, payback, eligibility, incentives, and rates vary and are not guaranteed. See our full disclaimer.
