| ZIP Codes: | 16 ZIP Codes (13 Standard, 3 PO Box, 0 Unique) [See All] |
| Area Code: | 509 |
| Timezone: | Pacific (GMT -08:00) |
| Local Time: | 2:14:16 PM |
| Population: | 100,402 [See All] |
| FIPS: | 53025 |
| CBSA: | Moses Lake, WA |
| Land Area: | 3,318 sq mi |
| Water Area: | 120 sq mi |
| Coordinates: | 47.3300, -119.4063 |
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100,402 residents live across 16 ZIPs covering 3,318 sq mi, served by 16 distinct USPS-recognized cities.
Population moved from 90,156 to 100,402 from 2014 to 2024 — a +11.4% change. 10 ZIPs gained residents, 6 lost.
The county's wealthiest ZIP 99123 (Electric City, $87,841 median) and poorest ZIP 99357 (Royal City, $57,034) are 75.0 miles apart — a 1.5× income gap across local geography.
Median home values vary 2.0× across this county — from $213,300 in 98857 (Warden) to $427,800 in 99349 (Mattawa).
Density varies 33× across the county — from 3 people/sq mi in 99115 (Coulee City) to 106 in 98837 (Moses Lake).
Educational attainment ranges from 12.1% bachelor's+ in 99349 (Mattawa) to 28.6% in 99123 (Electric City) — the breadth of educational profiles across the area.
Within Washington, this is the #13 most populous of 39 counties and ranks #31 for median household income with the #22 fastest decade growth .
Weighted by population, the typical household earns about $73,148 across the county — reflecting what a typical resident sees, not a simple ZIP average.
18.8% of adults age 25+ hold a bachelor's degree or higher (11,756 of 62,544 reporting).
13 Standard delivery, 3 PO Box only, 0 single-entity Unique ZIPs serve this county.
A frontier county — vast land area with only a few residents per square mile. Daily life looks very different here than in the country's denser counties.
| ZIP | City | Type | Population | Median Income | Area (sq mi) | 10-yr Growth |
|---|---|---|---|---|---|---|
| 98837 | Moses Lake | Standard | 49,455 | $74,586 | 468.2 | 20.9% |
| 98848 | Quincy | Standard | 12,854 | $87,714 | 468.1 | 7.2% |
| 98823 | Ephrata | Standard | 12,188 | $73,074 | 291.2 | 12.6% |
| 99349 | Mattawa | Standard | 8,143 | $61,333 | 331.8 | -4.6% |
| 98851 | Soap Lake | Standard | 4,437 | $63,333 | 188.8 | 12.9% |
| 98857 | Warden | Standard | 4,062 | $61,860 | 155.2 | 2.0% |
| 99357 | Royal City | Standard | 3,843 | $57,034 | 225.6 | -4.0% |
| 99115 | Coulee City | Standard | 1,369 | $62,708 | 433.2 | 4.6% |
| 99133 | Grand Coulee | Standard | 1,115 | $68,854 | 200.2 | -28.6% |
| 99321 | Beverly | Standard | 1,047 | $75,795 | 53.9 | 58.4% |
| 99123 | Electric City | Standard | 977 | $87,841 | 24.9 | -19.2% |
| 99135 | Hartline | Standard | 395 | $80,469 | 193.6 | 51.9% |
| 98860 | Wilson Creek | PO Box | 277 | $62,500 | 79.1 | 9.9% |
| 98824 | George | PO Box | 147 | $44,028 | 0.0 | -67.5% |
| 98832 | Marlin | Standard | 87 | $31,964 | 197.8 | -66.9% |
| 98853 | Stratford | PO Box | 6 | — | 6.5 | 200.0% |