Seattle, WA · 2026 cost guide
How much does a deck cost in Seattle?
In Seattle, a deck costs about $6,000–$24,000 in 2026 for a 320 sq ft deck, from pressure-treated to composite — roughly $18.8–$75.21 per square foot. That’s about 9% above the Washington average.
Estimate your Seattle project with the Deck Cost Calculator →
Seattle cost breakdown
| Seattle typical range | $6,000–$24,000 |
| Seattle per square foot | $18.8–$75.21 |
| Washington state average | $5,500–$22,000 |
| Versus Washington average | about 9% above average |
What’s different about Seattle
Seattle carries high labor and permitting costs, Cascadia seismic codes, and a wet maritime climate that together make it Washington's priciest market.
- Seismic bracing and stronger connectors add to structural cost.
- Rot- and mold-resistant or composite materials are favored in humid climates.
- Permit fees and skilled-trade labor rates here run well above the national average — usually the single biggest cost driver.
How the cost is built
Deck cost depends on size, decking material (pressure-treated pine is cheapest; composite and PVC are mid-range; tropical hardwood is premium), and structural extras like railings, stairs, and elevated footings. Permits and ledger flashing add cost on attached decks.
Frequently asked questions
How much does a deck cost in Seattle?
In Seattle, a deck costs about $6,000 to $24,000 in 2026 for a 320 sq ft deck, from pressure-treated to composite — roughly 18.8–75.21 per square foot. That's about 9% above the Washington average, reflecting local labor and permit costs.
What affects the cost of a deck in Seattle?
Seattle carries high labor and permitting costs, Cascadia seismic codes, and a wet maritime climate that together make it Washington's priciest market. Seismic bracing and stronger connectors add to structural cost.
How can I get an accurate deck building estimate in Seattle?
Use the free Deck Cost Calculator to plug in your real measurements, then collect two or three local Seattle quotes to compare. Prices vary by neighborhood, access, and project complexity.
Deck building cost in other Washington metros
Keep planning
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Open calculator →The Seattle figure scales the Washington cost range by a local metro index, then adjusts for the city’s labor market and climate. A 2026 planning estimate, not a quote — get local bids. See our methodology.