King County Home Building Costs
Building a house in King County, Washington costs about $249/sq ft in 2026 — roughly $498,000 for a 2,000 sq ft mid-range home (construction only, land excluded). Population: 2,300,000.
Local Market Factors
- ›Seattle/Amazon/Boeing
- ›Highest labor costs in state
- ›Tech sector premium
Cost by Home Size in King County
| Home Size | Basic | Mid-Range | Premium |
|---|---|---|---|
| 500 sq ft | $92,051 | $124,500 | $169,532 |
| 1,000 sq ft | $184,101 | $249,000 | $339,064 |
| 1,500 sq ft | $276,152 | $373,500 | $508,596 |
| 2,000 sq ft | $368,202 | $498,000 | $678,128 |
| 2,500 sq ft | $460,253 | $622,500 | $847,660 |
| 3,000 sq ft | $552,303 | $747,000 | $1,017,191 |
| 4,000 sq ft | $736,404 | $996,000 | $1,356,255 |
| 5,000 sq ft | $920,505 | $1,245,000 | $1,695,319 |
Costs are estimates only and represent construction costs, excluding land, architect fees, permits, and landscaping. Add 30–40% to these figures for total project cost.
County multiplier of 1.18× applied to Washington state average (which itself is 1.18× the national average of $179/sq ft).
Cost data: HouseBuildCalc Permit Cost Index (876,000+ building permits, 1,700+ ZIP codes), U.S. Census Bureau Survey of Construction, BLS Producer Price Index, NAHB Cost of Constructing a Home (published summaries). County-level multipliers are estimates derived from regional market data. For planning purposes only.