How to Compare Solar Quotes Side by Side

To compare solar quotes side by side, put every offer on the same basis: the cash price per watt, the expected yearly production in kWh, the equipment, the warranties and the full financing cost. A quote that looks cheaper by monthly payment can cost thousands more once you divide the cash price by the system's watts and add up loan fees.

Key takeaways

• Get several detailed written bids. The FTC and the U.S. Treasury both advise comparing more than one.
• Price per watt is the key number: cash price before incentives divided by system size in watts.
• EnergySage reported a median quote of $2.57 per watt in the first half of 2026; Berkeley Lab found installer medians ranging from about $2.4 to $6.3 per watt in 2025.
• Loans can hide dealer fees of 30% or more above the cash price, according to the CFPB.
• Do not let a quote count the federal 25D credit: it is not allowed for expenditures made after December 31, 2025.

Why you should compare solar quotes

Solar prices vary a lot from one company to the next. Berkeley Lab's August 2026 data update found that among the 100 largest residential installers, median prices ranged from about $2.4 to $6.3 per watt in 2025. About a quarter had medians below $3 per watt, and about one in ten were above $5. Even a single installer's own project prices typically spanned about $1 to $2 per watt.

On a 10 kW system, a $1 per watt difference is $10,000 (our math). That is why the FTC tells homeowners to compare detailed bids from several companies, and why the Treasury's consumer solar guidance says to gather several quotes so you can compare.

What to line up when you compare solar quotes side by side

Make a simple table with one column per quote. Here is an example worksheet. The three quotes are made up for illustration; only the math is real:

Item	Quote A	Quote B	Quote C
System size (kW DC)	10.0	9.6	10.4
Cash price before incentives	$26,000	$31,000	$27,500
Price per watt	$2.60	$3.23	$2.64
Estimated first-year production	14,000 kWh	13,500 kWh	15,000 kWh
Price per first-year kWh	$1.86	$2.30	$1.83
Workmanship warranty	10 years	25 years	10 years
Production guarantee	None	Yes	None
Battery included	No	No	No

In this example, Quote B costs the most per watt but offers a longer workmanship warranty and a production guarantee. Quote C has the best value per kWh. Your job is to decide whether the extras are worth the price gap.

The FTC says each written bid should show system size and expected output, the full installation cost including any building or electrical permit fees, any production guarantee and warranty terms. The Treasury guidance adds itemized work and materials, itemized costs including any fee changes over time, and the minimum power the system must produce.

How to calculate price per watt on any quote

1. Find the total cash price before any rebates or incentives.
2. Find the system size in kW DC. Multiply by 1,000 to get watts.
3. Divide the price by the watts.

Example: $27,500 ÷ 10,400 watts = $2.64 per watt. Then divide the same price by the first-year kWh estimate to see value per kWh, which rewards better designs and sunnier roof faces.

Then place each result against published reference points. These are not price limits, just markers for where a quote sits:

Reference point	Price per watt	What it measures
EnergySage national average (cost guide, June 2026)	About $2.60	Average marketplace quote, all sizes, before incentives
EnergySage median quote (first half of 2026)	$2.57	Median marketplace quote, before incentives
DOE modeled market price (2025Q1, 2024 dollars)	$2.95	Cost model of an 8 kW solar-only home system
Berkeley Lab cash-purchase median (2025, via Mercom)	$3.00	Prices actually paid by cash buyers
Berkeley Lab loan-financed median (2025, via Mercom)	$4.50	Prices of loan-financed systems, which often include fees

A quote below the EnergySage figures is competitive; one above the Berkeley Lab cash median deserves a clear explanation. Size matters too: EnergySage's June 2026 cost guide shows smaller systems costing more per watt, $2.78 at 5 kW versus $2.47 at 15 kW. Compare quotes of similar size, or see solar price per watt by system size.

Compare production estimates, not just size

Two 10 kW systems can produce very different amounts of power. EnergySage's PVWatts-based estimates for a 10 kW system (June 2026) range from about 10,938 kWh a year in Seattle to about 17,644 kWh in Phoenix. Within one home, shading and roof direction matter too.

• Check that each quote's estimate is in the same range. A much higher estimate deserves questions.
• Ask which tool produced the estimate and what shading losses were assumed.
• Compare estimated kWh with your last 12 months of use from your bills.
• Ask whether the company guarantees a minimum output, as the FTC suggests.

You can check estimates yourself with our solar panel calculator.

Compare financing and the true cost of each solar quote

The CFPB reported in 2024 that dealer fees often raise the cost of a solar loan by 30% or more above the cash price, and that lenders often leave the fee out of the stated APR. The CFPB also found that lenders often present the loan principal as a net cost that assumes a federal tax credit the borrower may not get.

Berkeley Lab's 2025 data, as reported by Mercom, shows the effect: the median price was $3.00 per watt for cash purchases and $4.50 per watt for loan-financed systems. Berkeley Lab notes that loan fees rolled into the upfront price may be part of the reason.

For every quote, ask for:

• The cash price in writing, even if you plan to finance
• The loan amount, APR, term and total of all payments
• Any dealer fee, origination fee or prepayment requirement
• Whether payments change if you do not make a lump-sum payment by a set date

The FTC also suggests asking about the APR, any balloon payment and whether you can cancel, and it warns that PACE financing puts a lien on your home that is repaid through your property tax bill. Read our guide to dealer fees in solar loans.

Check tax credit and savings claims

Many older sales templates still subtract a 30% federal credit. That is outdated for buyers. IRS guidance says the Section 25D credit is not allowed for expenditures made after December 31, 2025, and a solar expenditure is treated as made when installation is completed, even if you paid earlier. Ask for a corrected quote that shows the full price.

Lease and PPA quotes follow different rules because a company owns the system. EnergySage reports that third-party-owned projects can still qualify for federal incentives through 2027. That benefit goes to the owner, so compare those offers by the total you would pay over the contract.

Be careful with savings charts too. The FTC notes that future utility rates are hard to predict, and the Treasury guidance suggests asking whether advertised savings are guaranteed. If a quote assumes electricity prices will rise quickly every year, ask to see the payback with a lower rate of increase.

Compare the company, warranties and contract

A low price is not a bargain if the company cannot stand behind the work. The FTC suggests checking a company's record with state and local consumer protection agencies and your contractor licensing board, and confirming the licenses, certificates or bonding your state, county and city require. Also compare:

• Workmanship warranty length and what it covers, including roof leaks
• Panel and inverter warranty terms from the manufacturers
• Who handles maintenance and repairs after installation
• For leases or PPAs: whether payments rise over time and the cost of ending the contract early, both of which the FTC flags

The FTC also warns against any company that pressures you for a quick decision or will not give you time to review a contract. See questions to ask a solar installer before signing.

Next steps

Collect at least two or three detailed written quotes, fill in a side-by-side table like the one above and convert each to cash price per watt. Then upload your quotes to our solar quote checker for a second look before you sign.