9,790 of the 17,286 lots in Spanaway (57%) are zoned for houses inside an urban growth area. On those lots, Washington's HB 1337 requires the city or county to allow at least two accessory dwelling units (ADUs). Another 4,513 lots are outside the urban growth area, where Pierce County's own ADU rules decide.
5,764 of the 17,286 lots in Spanaway (33%) have septic records on file with the Tacoma-Pierce County Health Department. 15,915 lots are inside a Pierce County sewer service area, and 10,170 are within 300 feet of a sewer main on the county's sewer map.
Vacant land in Spanaway sold for a median of $144,908 per acre across 24 sales since November 1, 2023. Homes sold for a median of $498,000 across 2,124 sales. 1,033 new homes were permitted since November 1, 2021.
Of the 17,286 lots in Spanaway, 3,273 touch a mapped landslide hazard area, 1,185 an erosion hazard area, 448 a flood area and 746 an inventoried wetland, on Pierce County's maps.
From the Pierce County Assessor-Treasurer, the county's zoning, sewer, hazard and growth-area maps, and the Tacoma-Pierce County Health Department. Records as of November 8, 2026.
How these numbers are worked out · Guides