Residential Solar Cost per Watt in 2026: Real SEIA & EnergySage Data

The headline: cost per watt

Industry trackers including SEIA and EnergySage place the installed price of residential solar around $2.50–$3.50 per watt before any incentives in 2025–2026. That "per watt" figure is the cleanest way to compare quotes, because it strips out system size. A cheaper total can simply mean a smaller array, not a better price.

What a full system costs

A typical U.S. home system is roughly 7–10 kW. At ~$3/W that is about $21,000–$30,000 of gross cost before incentives. Before 2026, the 30% federal residential credit (Section 25D) took that to roughly $14,700–$21,000 net. With the credit expired, homeowners now pay closer to the full gross figure — which is why payback math changed so much for systems quoted in 2026.

Cost by system size

Gross installed cost tracks almost linearly with size at ~$2.50–$3.50/W: a 6 kW system lands near $15,000–$21,000, an 8 kW system near $20,000–$28,000, and a 10 kW system near $25,000–$35,000. These are national ranges; state labor rates, roof complexity, and equipment tier move individual quotes well outside the band.

What moves your price

Roof pitch and age (old or shaded roofs add cost or disqualify roof-mount), equipment tier (premium panels and microinverters cost more but often yield more energy), local labor rates, permit and interconnection fees, and whether battery storage is included. Getting three itemized quotes is the single best way to sanity-check a per-watt number.

The federal credit ended January 1, 2026

The 30% federal residential solar credit under Section 25D expired on December 31, 2025 and is not available for systems placed in service in 2026. Payback periods are therefore longer than 2023–2025 figures implied. Some states and utilities still offer their own incentives, so check your state's solar-incentive page before assuming the credit is the only lever.

Is $3 per watt still realistic in 2026?

Yes for many markets, but it is a range, not a fixed price. SEIA and EnergySage data put installed residential solar around $2.50–$3.50/W in 2025–2026; high-labor or complex-roof installs can run higher.

How much did losing the 30% credit add to payback?

Roughly a third more out of pocket versus 2023–2025, since the 30% federal credit is gone for 2026 systems. The exact payback shift depends on your electricity rate, system size, and any remaining state incentives.

Does solar still pencil out without the federal credit?

Often yes in high-electricity-rate states and sunny regions, but the case is weaker than it was. Model your own numbers with the PVFig Solar ROI Calculator using current (no-credit) costs and your state production data before committing.