Home > WA > Cowlitz County > Castle Rock > Zip 98611

Zip Code 98611 — Castle Rock, WA

ZIP Code 98611 is associated with Castle Rock, WA, in Cowlitz County. The listed population estimate is 9,302; estimated density is 26.4 people per square mile. Among records with population estimates, it ranks #4 of 9 in Cowlitz County and #240 of 597 in WA.
Page generated: 2026-10-08. This is not the source data release date.

📍 View location on OpenStreetMap (46.306420, -122.904790)

Data MetricLocal Statistic
Postal / Zip Code98611
Primary CityCastle Rock
State / ProvinceWA
CountyCowlitz
Total Population9,302
Population Density26.4 people/sq mi
TimezoneAmerica/Los_Angeles

How 98611 Compares

MetricZIP 98611Cowlitz County recordsWA records
Population estimate9,302116,840 (sum)7,816,021 (sum)
Population Density26.4 /sq mi----
County population rank#4 of 9----
State population rank#240 of 597----

Regional sums combine the population estimates in the listed ZIP records; they are not official county or state population totals.

Explore More ZIP Codes

Nearby ZIP Codes in WA

ZIP CodeCityDistancePopulation estimate
ZIP 98645Silverlake6.1 mi2,216
ZIP 98593Vader8.6 mi1,541
ZIP 98581Ryderwood8.6 mi419
ZIP 98632Longview10.2 mi50,635
ZIP 98626Kelso12.0 mi26,892

Data Sources & Methodology: Geographic coordinates and ZIP Code assignments are derived from underlying geographic and postal datasets. Note that ZIP Codes are USPS postal delivery areas, while Census ZCTAs are statistical approximation areas. Read full methodology →