ZIP Code 98558 in Mckenna, WA

Mail Demand Exceeds Local Population

McKenna's post office serves a territory far larger than the tiny community at its center. With just 38 occupied homes in the immediate area, the post office maintains 763 PO Boxes. That's a 20-to-1 ratio. This isn't a quirk of geography. It's what happens when rural communities across southern Pierce County need a reliable place to receive mail.

This is a PO Box Only Zone. Across the service area, there's no alternative mail delivery. Residents drive to McKenna from farms, homesteads, and rural properties scattered across the foothills between Tacoma and Mount Rainier. The post office sits on a compact 0.34 square miles, but its reach extends across miles of countryside.

Local Demographics

The 134 people living within the ZIP boundary are mostly younger families. Median age is 34. Per capita income is $42,725. About 75% are White (101 residents), with a mix of other backgrounds. Of the 48 total housing units, 32 are owner-occupied and just 6 are rentals. Another 10 units sit vacant, with 5 used seasonally.

Street Pattern and Layout

Streets follow a numbered grid pattern. The main artery is 350th Street South, which accounts for 58 delivery records and includes multi-unit addresses. Other streets include 356th Street South, 355th Street South, and State Route 507 running through town. The street names reflect Pierce County's methodical numbering system rather than local landmarks.

Surrounding Communities

Nearby Fort Lewis sits 8.8 miles to the north. Other surrounding communities include Elk Plain (9.9 miles), Spanaway (10.8 miles), Graham (11.6 miles), and Frederickson (12.5 miles). Many military families, rural residents, and people living between these towns use McKenna as their mailing address.

Mixed Delivery Pattern

Mail delivery here uses a mix of city and rural carrier routes. There are 59 city route records and 23 rural route records, plus 15 PO Box route records. That combination shows the post office serves both the compact town center and the spread-out countryside. The 11 business establishments employ 91 people, giving McKenna a small commercial presence beyond its residential core.

Mailing to McKenna

Because this is a PO Box Only Zone, most addresses use PO Box format:

Recipient Name
PO Box [number]
McKenna, WA 98558

Some street addresses exist for business delivery, but PO Boxes remain the primary method for the vast majority of the service area.

Street Name Patterns

Street names follow Pierce County's numbered grid system, with 350th Street South serving as the main delivery corridor.

Nearby Areas