How Much Does a 10 kW Solar System Cost in 2026?

A 10 kW solar system costs about $25,800 before incentives, according to EnergySage marketplace data (page updated June 24, 2026). That is about $2.58 per watt. EnergySage's state averages for this size run from $20,390 in Texas to $29,693 in Massachusetts, so where you live matters as much as the system size.

Key takeaways

• EnergySage's average 10 kW price was $25,800 before incentives as of June 2026.
• Price per watt (cash price divided by 10,000 watts) is the fairest way to compare 10 kW quotes.
• EnergySage's PVWatts-based estimate is about 14,517 kWh a year for 10 kW at the U.S. average location.
• Berkeley Lab data shows loan-financed systems had a much higher median price in 2025 than cash purchases, so ask for both prices.
• The federal 25D homeowner credit is not allowed for expenditures made after December 31, 2025.

How much does a 10 kW solar system cost in 2026?

Three well-known data sets give different answers because they measure different things. EnergySage tracks quotes on its marketplace. Berkeley Lab tracks installed prices reported to state agencies and utilities. The U.S. Department of Energy publishes a bottom-up cost model, with analysis by the National Laboratory of the Rockies (NLR, formerly NREL), Berkeley Lab and Sandia. The table applies each one to a 10 kW system. The dollar column is our own multiplication, not a quote.

Price per watt	10 kW at that price (our math)	Source and date
$2.25/W	$22,500	Lowest state average in EnergySage's cost guide (Arizona and Texas, June 2026)
$2.58/W	$25,800	EnergySage 10 kW average (June 2026)
$2.95/W	$29,500	DOE modeled market price, 8 kW solar-only home system, first quarter of 2025 (2024 dollars)
$3.00/W	$30,000	Berkeley Lab median for cash purchases, 2025, as reported by Mercom
$3.60/W	$36,000	Berkeley Lab median for all host-owned home systems, 2025, as reported by Mercom

EnergySage's first-half 2026 market report put its median quote at $2.57 per watt across all system sizes, up about 3% from the second half of 2025. Berkeley Lab's numbers run higher because they cover systems actually installed in 2025, including financed ones. Mercom, reporting Berkeley Lab's August 2026 data update, gives an inflation-adjusted median of $3.60 per watt for host-owned home systems in 2025, down from $4.10 in 2024.

The DOE benchmark modeled an 8 kW rooftop system. It is a model, not a survey of bills, but a 10 kW system is close enough in size that its per-watt figure is a useful sanity check.

10 kW solar system cost by state

EnergySage's average 10 kW prices before incentives, as of June 2026. The per-watt column is our division.

State	Average 10 kW price	Per watt
Texas	$20,390	$2.04
Florida	$21,188	$2.12
Arizona	$22,825	$2.28
California	$24,515	$2.45
New Jersey	$25,532	$2.55
Washington	$25,996	$2.60
Colorado	$26,831	$2.68
New York	$27,643	$2.76
Maryland	$27,764	$2.78
Massachusetts	$29,693	$2.97

EnergySage's size pages and its general cost guide draw on different sets of quotes, so their state figures do not match exactly. Treat both as rough guides. If your state is not listed, our solar data by state shows local sunshine and electricity prices.

Why 10 kW solar quotes differ

Two homes can get very different prices for the same 10 kW size. The biggest reasons:

• The installer. Berkeley Lab found that median prices among the 100 largest residential installers ranged from about $2.4 to $6.3 per watt in 2025. On 10 kW, that spread is roughly $24,000 to $63,000 (our math).
• Cash or loan. The CFPB reported in August 2024 that dealer fees often raise solar loan costs by 30% or more above the cash price. Those fees are usually folded into the loan amount.
• A battery. EnergySage reported battery pricing of $1,130 per kWh in the first half of 2026.
• The roof. EnergySage says roofs with several planes, dormers or skylights need more equipment and labor, and trimming or removing shade trees can cost $300 to $1,500.
• Permits and fees. EnergySage estimates these can add a few thousand dollars, about 8% of total cost.

Price per watt math for a 10 kW quote

Find the system size in kW DC on the quote, multiply by 1,000, then divide the cash price before incentives by that number.

Example: a $27,000 quote for 10.2 kW is $27,000 ÷ 10,200, or about $2.65 per watt. A $30,000 quote for 10 kW is $3.00 per watt. The second quote costs $3,000 more for a slightly smaller system. If a quote only shows a monthly payment, ask for the cash price in writing. Our guide on what price per watt is too high covers the warning signs.

How much electricity does a 10 kW solar system produce?

EnergySage used PVWatts to estimate yearly output for a 10 kW system in different cities:

• Phoenix: about 17,644 kWh
• Austin: about 14,775 kWh
• U.S. average location: about 14,517 kWh
• Boston: about 13,098 kWh
• Seattle: about 10,938 kWh

The EIA says the average U.S. home bought 10,791 kWh of electricity in 2022, or about 899 kWh a month. Every city on EnergySage's list comes in above that figure for 10 kW, which is why EnergySage calls this size enough for most American homes. It also notes that your home may not be average: heavy air conditioning, EV charging or pool heating can push you higher, and modest use can mean you need less.

Before you accept a 10 kW design, total 12 months of kWh from your bills and run them through our solar panel calculator. As a rough estimate, 10 kW built from 400-watt panels would be 25 panels; higher-wattage panels mean fewer.

Tax credits and incentives for a 10 kW system

If you buy, there is no federal credit for a system finished now. IRS guidance says the Section 25D residential clean energy credit is not allowed for expenditures made after December 31, 2025, and a solar expenditure is treated as made when the original installation is completed. Paying a deposit in 2025 does not change that if installation finished in 2026.

Leases and power purchase agreements (PPAs) are different because a company owns the panels. EnergySage reports that third-party-owned projects can still qualify for federal incentives through 2027. That benefit goes to the owner, so ask how it shows up in your monthly rate.

State and local help still exists in some places. EnergySage lists cash rebates, net metering, performance-based incentives and SRECs as ways to recover costs, but eligibility depends on where you live. Check your utility's net metering tariff before you estimate payback.

Checking a 10 kW quote before you sign

The FTC says written bids should state the system size and expected output, the full cost of installation including any building or electrical permit fees, whether output is guaranteed, and the equipment and workmanship warranties. For a 10 kW system, a quick check looks like this:

• Is the cash price per watt close to the EnergySage averages above for your state?
• Is the first-year kWh estimate in a believable range for your city?
• Are panel and inverter models named, not just "premium panels"?
• If you finance, are the APR and any dealer fee shown in writing?

Our walkthrough on how to compare solar quotes side by side has a full worksheet.

Next steps

Collect two or three written quotes, convert each to cash price per watt and compare the production estimates. Then upload them to our solar quote checker to see how your price compares before you sign.