Solar installation cost in Seattle

Computed from 39 recent building-permit filings in Seattle, WA — what people actually declared, not survey guesses.

Typical low · P25$19,330
Median$33,824
Typical high · P75$40,000

✓ Verified from 39 recent building-permit filings in Seattle, WA

Data refreshed July 2026

The short answer: a typical solar installation in Seattle costs around $33,824, with half of all projects landing between $19,330 and $40,000. If a quote falls well outside that range, it isn't automatically wrong — but it deserves an explanation you can understand.

Before you spend on a solar installation

💸 What drives the cost

  • System size (kW) and panel count — but price per kW falls as systems grow
  • Battery storage can add 40–80% to the total; it's a separate decision from panels
  • Roof condition and orientation: re-roofing first is cheaper than removing and re-mounting panels later

✂️ How to spend less

  • Get quotes in price-per-kW to compare like for like
  • If your roof is over ~15 years old, replace it before, not after, installation
  • Check export tariffs (UK SEG) and local incentives before sizing the system

🚩 Red flags when hiring

  • Lease/PPA structures pitched without showing the total cost of ownership vs buying outright
  • Savings projections assuming electricity prices rising 8–10% every year

Next steps for your solar installation

Get contractor quotes

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Solar installation in other cities

Other projects in Seattle

Where this number comes from

Every figure on this page is computed from declared valuations on building permits published by Seattle's open-data portal. We report the 25th percentile, median and 75th percentile of 39 recent residential filings — never a single-point "average". Declared values are what applicants file, not final invoices, so treat the range as planning guidance rather than a quote. Full methodology →

Questions people ask

How much does a solar installation cost in Seattle?

Based on 39 recent building-permit filings in Seattle, the median declared cost is $33,824. Half of all projects fall between $19,330 and $40,000.

Are these figures quotes?

No. Permit valuations are what applicants declare when filing, not final invoices. Treat the range as planning guidance and a sanity-check against the quotes you receive.

Why is the range so wide?

Because identical-sounding projects legitimately differ in size, specification and site conditions. That is why we publish the 25th percentile, median and 75th percentile instead of a single misleading "average" — you can see where a quote sits in the real distribution.

Planning something else, or somewhere else? Request a city or project — requests decide what we ingest next.