The Unshakable Investor

Unshakable ZIP Data 98188 | Seatac, WA Housing Market

Seatac · King County · Seattle-Tacoma-Bellevue, WA metro · Washington · Data updated June 19, 2026

The median sale price in ZIP 98188, Seatac, Washington is $608,819 at $324 per square foot. 30 single-family homes sold in the latest period, down 25.4 percent from a year earlier. Homes sit a median of 6 days on market with 4.1 months of supply. Sellers are getting 99.7 percent of list price and 24.1 percent of homes sold above asking.

Balanced market.

Value anchors

MetricValueYear over year
Average single-family value$636,310
Average price per sq ft$339
Median sale price$608,819
Median sale price per sq ft$324
Median home size1,877 sq ft
Median new listing price$594,915+25.3%
National size rank4,326

Sales activity

MetricValueYear over year
Homes sold30-25.4%
Median days on market6 days
Months of supply4.1 months
New listings56-16.7%
Active listings78-9.3%
Pending sales39-23.0%

Pricing power

MetricValueYear over year
Average sale-to-list ratio99.7%-0.2 pts
Share sold above list24.1%-0.9 pts

Bedroom value anchors

Average values by bedroom count. Value anchors for orientation, not appraisals.

1-bedroom
$209,063
2-bedroom
$338,462
3-bedroom
$599,030
4-bedroom
$703,910
5-bedroom
$795,548

These figures describe the single-family market for Seatac, Washington ZIP 98188. They are market context, not a substitute for sold comps or a formal appraisal.