Solar Panel Cost in 2026: Price per Watt, by System Size and State

Solar panel cost is almost always quoted two ways: a total dollar figure for the system and a price per watt (W) of panel capacity. The per-watt number is the one that lets you compare quotes, because it strips out system size. This guide uses the two most-cited independent sources in the US: Lawrence Berkeley National Laboratory’s (LBNL) Tracking the Sun dataset of real installed prices, and NREL’s bottom-up cost benchmarks. It then works through cost by system size, what moves the price between states and installers, payback, and what changed when the 30% federal credit ended. To size a system for your own bills, use the solar panel calculator.

How much do solar panels cost in 2026?

For homes installed in 2025, the latest full year of data, LBNL’s median price for host-owned residential solar was $3.60 per watt, down from $4.10/W in 2024. Cash buyers paid a median $3.00/W.

These figures come from Berkeley Lab’s U.S. Distributed Solar and Storage Data: 2026 Update, which covers project-level data from millions of systems installed through the end of 2025. The headline medians for 2025 installs:

Segment (2025 installs)	Median installed price	2024 for comparison
Residential, all host-owned	$3.60/W	$4.10/W
Residential, cash purchase	$3.00/W	$3.60/W
Residential, loan-financed	$4.50/W	$4.80/W
Residential solar + storage	$4.90/W	—
Small non-residential	$3.10/W	—
Large non-residential	$2.40/W	—

Source: LBNL 2026 data update (2025 installs), inflation-adjusted, before incentives. Medians read from the 2026 data update slide deck (slides 8–9, 2025 dollars); see the report page for the full distribution. Cash and loan medians cover only the ~45% of host-owned systems whose financing type LBNL could identify with high confidence (slide 8 note).

The median residential system was 7.7 kW (LBNL, slide 4), and among the top 100 installers median prices ranged from about $2.40/W to $6.30/W (LBNL, slide 38), a gap of more than 2.5x for broadly similar hardware. That spread is the single most useful fact for anyone shopping: who installs the system matters as much as which panels go on the roof.

Online marketplaces quote lower averages than LBNL’s medians because they only report quotes from their own installer networks, which are skewed toward competitive bids. Treat those as the price you might get with aggressive shopping, and LBNL as what households actually paid.

Why loan-financed systems cost more per watt

The $1.50/W gap between cash ($3.00) and loan ($4.50) medians is mostly not hardware. Many solar loans carry a “dealer fee” that is built into the system price so the lender can offer a lower advertised interest rate. If you are financing, ask the installer for the cash price and the financed price side by side; the difference is the real cost of the loan. The FTC’s solar guidance recommends getting the total cost, financing terms and any fees in writing before signing.

Solar panel cost by system size

Multiply system size in watts by the price per watt. At LBNL’s 2025 medians, a 7.7 kW system costs about $23,100 (cash) to $27,700 (all buyers).

System size	At $3.00/W (cash median)	At $3.60/W (overall median)	At $4.50/W (loan median)
4 kW	$12,000	$14,400	$18,000
6 kW	$18,000	$21,600	$27,000
7.7 kW (median)	$23,100	$27,720	$34,650
10 kW	$30,000	$36,000	$45,000
12 kW	$36,000	$43,200	$54,000
15 kW	$45,000	$54,000	$67,500

Arithmetic only: size × LBNL 2025 median $/W. Real quotes have some fixed costs (permits, design, interconnection), so very small systems usually cost more per watt and larger ones a little less.

How big a system you need depends on your annual kWh use and your local sunshine. A rough rule: system kW ≈ annual kWh ÷ (yearly kWh produced per kW at your address). NREL’s free PVWatts gives the production per kW for any US address; our solar panel calculator does the whole calculation from your monthly bill.

Cost of a 10 kW solar system

At the 2025 medians a 10 kW system lands between about $30,000 (cash) and $36,000, before any state or utility incentive. A 10 kW array suits a high-use home, for example one with an electric vehicle or a heat pump; check the cost to charge an electric car to see how much EV load adds.

Cost of a 5 kW or 20 kW system

A 5 kW system is about $15,000 to $18,000 at the same medians; a 20 kW system $60,000 to $72,000. Twenty kilowatts is well above the median home and usually needs a large roof or a ground mount, which adds racking and trenching cost.

What are the soft costs, and why do they matter?

Most of what you pay for home solar is not the panels. Customer acquisition, permitting, inspection, interconnection, installation labor, overhead and margin make up the bulk of a residential quote.

NREL’s benchmark separates prices into hardware and soft costs and models two numbers. The modeled market price (MMP) is what a company actually charges; the minimum sustainable price (MSP) is the lowest price a company could charge and stay solvent long term. For a residential system in Q1 2023, NREL put the MMP at $2.90/Wdc and the MSP at $2.34/Wdc; the MMP was 9% below its Q1 2022 value of $3.18/Wdc (NREL Q1 2023 benchmark; summary in pv magazine USA).

Use these two numbers as guard rails when reading quotes:

• Near or above $3.60/W (LBNL overall median): ask what is driving the price. Premium panels, a complex roof, a main-panel upgrade or a financing fee can each justify part of it.
• Around $2.90–3.00/W: in line with NREL’s modeled market price and LBNL’s cash median.
• Well below $2.34/W: below what NREL modeled as sustainable. That is possible for very large or very simple systems, but check warranties, equipment brands and the installer’s track record.

Permitting is one soft cost you can see coming; our guide to the solar panel installation permit covers what jurisdictions require.

Solar panel cost by state

Installed prices differ by state, but the bigger driver is the installer and market structure, not the state line. Payback differs far more than price, because electricity rates and export credits vary so much.

Berkeley Lab’s Tracking the Sun publishes median prices by state each year, and its downloadable data lets you filter to your own state and recent years. We have deliberately not printed a 50-state price table here: per-state medians shift year to year, small states rest on few systems, and we could not verify a current table from the primary report. Instead, these are the factors that make one state cheaper or more expensive:

1. Market size and competition. States with many installers tend to have lower median prices; research using Tracking the Sun data links more competition to lower prices (Gillingham et al., 2016).
2. Permitting and interconnection rules. Faster, standardised permitting cuts soft costs; slow or bespoke processes add labor and overhead.
3. Labor costs vary with local wages.
4. Incentive design. Generous rebates can let installers hold prices up, a pattern economists have studied (Gillingham et al., 2016).
5. Export credit rules. These do not change the price, but they change payback. California’s net billing tariff, for example, credits exports below retail, which is why batteries are now common there.

For the electricity rate side of the equation, see the electricity cost calculator, which uses EIA state averages.

Is solar worth it without the 30% tax credit?

The federal residential clean energy credit is gone for new purchases: the IRS says the §25D credit is not allowed for expenditures made after December 31, 2025, and an expenditure counts as made when the installation is completed.

The IRS FAQ on the One Big Beautiful Bill Act adds that paying before year-end does not help if installation finished in 2026. Systems a homeowner buys and installs in 2026 therefore pay the full sticker price unless a state, utility or local program helps. Search DSIRE by ZIP code for those.

Whether solar is still worth it comes down to three numbers: your net price per watt, how many kWh each kW produces where you live, and what each kWh is worth to you.

Worked example: payback on a median system

Assumptions (all stated, change them for your home):

• System: 7.7 kW (LBNL 2025 median size).
• Price: $3.00/W cash median → 7,700 W × $3.00 = $23,100.
• Production: 1,300 kWh per kW per year (an assumption; check your address in PVWatts) → 7.7 × 1,300 = 10,010 kWh/yr.
• Value: 18.2¢/kWh, the US average residential price (EIA, August 2026), assuming every kWh offsets a retail kWh → 10,010 × $0.182 = $1,822/yr.

Simple payback = $23,100 ÷ $1,822 ≈ 12.7 years. At the $3.60/W overall median ($27,720), payback is about 15.2 years.

Cost per kWh over 25 years: panels lose roughly 0.5% of output a year (Jordan & Kurtz, 2013; NREL). Summing 25 years of output at that rate gives about 23.56 × 10,010 ≈ 235,800 kWh, so $23,100 ÷ 235,800 ≈ 9.8¢/kWh, before inverter replacement and maintenance. That is about half the average retail rate, which is why solar can still pay off without the credit where rates are average or high and exports are credited fairly. Where rates are low, or exports earn much less than retail, payback stretches out.

How much does a solar battery add?

LBNL’s 2025 median for residential solar plus storage was $4.90/W, versus $3.60/W for solar alone. The median battery was 13.5 kWh, and 37% of new residential systems included storage, up from 25% in 2024.

Source: LBNL 2026 data update, slides 5–6 (attachment rate, battery size) and 9 (PV+storage price). About 80% of the PV+storage price data comes from California, so treat the premium as indicative elsewhere.

On a 7.7 kW system, $1.30/W extra is about $10,000. A battery rarely shortens payback on its own where net metering is generous; it pays where exports are credited below retail or where backup during outages has real value to you. For a fully off-grid home, the economics are different again; see the off-grid solar system guide and the off-grid solar calculator.

Buying, financing or leasing

Option	Up-front cost	Who owns it	Watch out for
Cash	Full price	You	Lowest median $/W (LBNL: $3.00)
Solar loan	Little or none	You	Dealer fees inside the price (LBNL loan median $4.50/W)
Lease / PPA	None	The provider	Shared savings, escalators, home-sale complications (FTC)

About 40% of new residential systems installed in 2025 were third-party owned (leases and PPAs), per LBNL, slide 11. The end of §25D applies to the homeowner credit; ask any lease or PPA provider how their pricing reflects the incentives they claim. Read the escalator clause carefully: a payment that rises every year can erase the savings over a 20-year contract.

How to get a fair solar quote

1. Get three or more written quotes and compare them in $/W, not total dollars.
2. Ask for the cash price even if you plan to finance.
3. Check the production estimate against PVWatts for your address and roof direction. An estimate far above PVWatts is a red flag.
4. Compare equipment and warranties: panel brand, inverter type, workmanship warranty length.
5. Ask who pulls the permit and handles interconnection, and whether a main-panel upgrade is included.
6. Run your own numbers with the solar panel calculator and check the best tilt with the solar panel angle calculator.

History: how US solar prices have been tracked

Modern residential price tracking began when subsidy programs needed data. Berkeley Lab publishes Tracking the Sun, compiling project-level prices reported to state incentive programs and utilities; the dataset now spans millions of systems and is the basis of the medians above (LBNL).

Hardware prices had been falling on a learning curve for decades: Richard Swanson showed in 2006 that module price fell steadily with each doubling of cumulative shipments (Swanson, 2006). By the early 2010s, researchers noticed that US installed prices remained far higher than Germany’s for similar systems. Seel, Barbose and Wiser traced most of that gap to soft costs such as customer acquisition, installation labor and permitting (Energy Policy, 2014). Gillingham and colleagues then used the Tracking the Sun data to show how market structure, competition and incentives shape what installers charge (Energy Journal, 2016).

That research shaped policy: soft costs became the main target of federal programs, and NREL added its minimum sustainable price to show how far market prices sat above a lean but viable price. The other big policy lever, the 30% residential credit, ended for homeowner purchases after 2025 (IRS). For the longer story of panel prices since the 1950s, see solar energy pros and cons.

Scientific references

• Swanson, R. M. (2006). “A vision for crystalline silicon photovoltaics.” Progress in Photovoltaics: Research and Applications, 14(5), 443–453. doi:10.1002/pip.709
• Seel, J., Barbose, G. L. & Wiser, R. H. (2014). “An analysis of residential PV system price differences between the United States and Germany.” Energy Policy, 69, 216–226. doi:10.1016/j.enpol.2014.02.022
• Gillingham, K. et al. (2016). “Deconstructing Solar Photovoltaic Pricing: The Role of Market Structure, Technology, and Policy.” The Energy Journal, 37(3), 231–250. doi:10.5547/01956574.37.3.kgil
• Jordan, D. C. & Kurtz, S. R. (2013). “Photovoltaic degradation rates — an analytical review.” Progress in Photovoltaics: Research and Applications, 21(1), 12–29. doi:10.1002/pip.1182