How Do You Compare Solar Quotes?
Quick answer: Put every quote in the same terms, then compare price per watt, estimated yearly production, the exact equipment, the warranties and the full cost of any financing. The cheapest quote isn’t always the best deal if it assumes more output, uses weaker warranties or hides fees in a loan.
Solar quotes can be hard to line up. One installer quotes a bigger system, another uses different panels, a third leads with a monthly payment. The way through is to put every quote into the same terms and then look at what’s different.
It helps to get at least three. Prices for the same size system can vary a lot between installers in the same town.
Ask every installer for the same details
Before comparing, make sure each quote spells out:
- System size in kilowatts (kW), and the number of panels
- The exact panel and inverter models, not just the brand
- Estimated production in kWh per year, and what it assumes about shade and roof direction
- Total price before any incentives, and what that price includes (permits, utility paperwork, monitoring, any electrical panel upgrade)
- Every warranty, with its length and who stands behind it
- Payment terms, including the cash price if you’re being offered financing
Compare price per watt
Divide the total price by the system size in watts. A $21,000 quote for an 8 kW (8,000 W) system works out to $2.63 per watt. This is the simplest way to compare systems of different sizes.
For reference, EnergySage’s marketplace average was $2.60 per watt in September 2026, with state averages from about $2.12 in Florida to $3.81 in Alabama. A quote far above your area’s range deserves questions. One far below it deserves a close look at what’s missing.
Check the production estimate
Price per watt tells you what you’re paying. The production estimate tells you what you’re getting. If two installers quote the same size system on the same roof and one claims much higher output, ask why. It may be a different layout, better equipment or just optimistic assumptions.
You can check an estimate yourself with PVWatts, a free tool from the National Laboratory of the Rockies (formerly NREL), or get a rough number from our solar calculator. The system should also be sized to your actual use. Our guide to how many panels you need explains how.
Look at the equipment
- Panels. Most panels sold for homes today are 21% to 24% efficient. Higher efficiency matters most when roof space is tight. See the most efficient solar panels.
- Inverters. Quotes will use a string inverter, microinverters or power optimizers. Each handles shade and monitoring differently. Our inverter guide compares them.
- “Tier 1” panels. This label comes from BloombergNEF and describes panels from makers whose products banks have financed in large projects. BloombergNEF says it isn’t a measure of quality, so ask for the model number instead.
Compare warranties
There are usually three kinds:
- Product warranty on the panels, covering defects. Many run 25 years, though some are shorter.
- Performance warranty, which guarantees the panels will still produce a set share of their rated output after 25 years or more.
- Workmanship warranty from the installer, covering the installation itself, including roof leaks from mounting. Lengths vary a lot between companies, so get it in writing.
Inverter warranties differ too. Microinverters often come with 25-year warranties, while string inverters are more often covered for 10 to 12 years.
A warranty is only as good as the company behind it. When SunPower went bankrupt in 2024, the company that bought its brand didn’t take on the old warranties. Ask who would honor the warranty if the installer closed.
Read the savings estimate carefully
Most quotes include a savings projection. Check what it assumes:
- Tax credits. The 30% federal credit ended for home systems installed after 2025. A cash or loan quote that still counts it is out of date.
- Electricity price increases. A projection that assumes rates rise quickly will show bigger savings. Compare quotes using the same assumption.
- Net metering. Make sure the estimate uses your utility’s current rules for power you send back. See how net metering works.
Compare financing on total cost
If a quote comes with a loan, lease or PPA, compare what you’d pay over the whole term. The Consumer Financial Protection Bureau found that solar loans often include hidden dealer fees of 10% to 30% of the cash price, built into the system price. Ask for the cash price and the financed price side by side. Our guide to leases, loans and cash covers the trade-offs.
Check the company
- Confirm it holds the contractor or electrical license your state requires, and carries insurance.
- Ask whether its own crews will do the work or whether it uses subcontractors.
- Look at how long it has been installing in your area and read reviews from several sites.
- Ask who handles permits, inspections and the utility’s approval to turn the system on.
Red flags
- Pressure to sign the same day, or a “price good only today”
- Claims of “free” solar or a special government program. The Federal Trade Commission says free or no-cost solar offers are scams, and it warns about sellers who pose as government or utility representatives.
- Promises that your electric bill will disappear entirely
- A quote with no specific equipment models or no production estimate
- Savings that depend on tax credits or rebates you can’t confirm
