MySunROI

Solar Cost Per Watt Explained (2026)

Published 2026-02-20 · Updated 2026-07-07 · MySunROI Research Team

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Cost per watt ($/W) normalizes solar pricing across system sizes. A $18,000 6 kW system = $3.00/W. Compare quotes using $/W before incentives, then apply the 30% ITC.

How to calculate

$/W = Total system price ÷ (kW × 1,000). Example: $21,000 ÷ 6,000W = $3.50/W.

2026 US ranges

  • Budget: $2.50–$2.90/W
  • Average: $2.90–$3.40/W
  • Premium (complex roof, battery): $3.40–$4.50/W
  • Cost by state

Solar costs by state

Frequently Asked Questions

Before or after tax credit?

Compare pre-incentive $/W for apples-to-apples, then calculate net cost after ITC.

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