As of 2026, the average cost of residential solar panels in the U. This typically translates to about $2. 50 per watt of installed capacity (more on price per watt below). solar calculator — enter your ZIP code and electricity bill, and it returns your recommended system size in kW, the number of panels, the roof area you need, the gross install cost, the annual savings, the payback period, the 25-year lifetime profit, and the CO₂ offset. Built on. Caution: Photovoltaic system performance predictions calculated by PVWatts ® include many inherent assumptions and uncertainties and do not reflect variations between PV technologies nor site-specific characteristics except as represented by PVWatts ® inputs. The total price depends on your system size, location, roof type. Solar panels cost about $21,816 on average when purchased with cash or $26,004 when purchased with a loan for a 7. Panels can cost as low as $1,890 and as high as $13,600. Combined with the tax credit, homeowners can achieve payback periods of just 6-10 years. Significant Regional Variations: Solar costs vary.