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County ZIP codes · Washington · FIPS 53045

Mason County, WA ZIP Codes

Mason County, Washington has 12 ZIP codes (Census 2020 ZCTA-county file; GeoNames postal codes, October 2026), all residential. 9 of the residential ones lie mainly in Mason County and 3 mainly in a neighboring county; 3 cross the county line. Median household income ranges from $61,975 in 98588 (Tahuya) to $125,229 in 98380 (Seabeck) (Census Bureau, ACS 2020-2024).

  • ACS2020-24
  • Census2020

Where are the ZIP codes of Mason County?

98380 · Seabeck: $125k98524 · Allyn: $100k98528 · Belfair: $91k98541 · Elma: $79k98546 · Grapeview: $97k98548 · Hoodsport: $69k98555 · Lilliwaup: –98557 · McCleary: $79k98560 · Matlock: $73k98584 · Shelton: $79k98588 · Tahuya: $62k98592 · Union: $138k98584985419854898528983809858898560985469855598592985579852498380 · Seabeck: $125k98524 · Allyn: $100k98528 · Belfair: $91k98541 · Elma: $79k98546 · Grapeview: $97k98548 · Hoodsport: $69k98555 · Lilliwaup: –98557 · McCleary: $79k98560 · Matlock: $73k98584 · Shelton: $79k98588 · Tahuya: $62k98592 · Union: $138k9858498541985489852898380985609854698555985929855798380 · Seabeck: $125k98524 · Allyn: $100k98528 · Belfair: $91k98541 · Elma: $79k98546 · Grapeview: $97k98548 · Hoodsport: $69k98555 · Lilliwaup: –98557 · McCleary: $79k98560 · Matlock: $73k98584 · Shelton: $79k98588 · Tahuya: $62k98592 · Union: $138k98584985419854898528983809856098546985559859298557
The residential ZIP codes of Mason County (whole outlines, including the parts in neighboring counties), shaded by median household income in national fifths (ACS 2020-2024). <$54.1k$98.1k+no figure

Source: U.S. Census Bureau, 2020 ZCTA cartographic boundaries; ACS 2020-2024 5-year estimates (B19013).

How different are its ZIP codes?

The middle half of its ranked ZIP codes (1,000+ people living in households) report median household incomes between $78,594 and $97,159.

They carry 12 postal town names.

Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B19013).

All 12 residential ZIP codes in Mason County

9 ZIP codes lie mainly in Mason County; 3 more reach into it from a neighboring county and follow the first table.

Residential ZIP codes mainly in Mason County, largest first; "In this county" is the share of the ZIP's land in the county
In this county
98584 Shelton 40,606 113 $79k $393k 100%
98528 Belfair 11,940 165 $91k $430k 100%
98524 Allyn 4,300 525 $100k $527k 100%
98546 Grapeview 2,430 71 $97k $495k 100%
98548 Hoodsport 2,177 11 $69k $315k 100%
98588 Tahuya 2,114 47 $62k $336k 100%
98592 Union 2,059 116 $138k $558k 100%
98555 Lilliwaup 324 12 – $463k 100%
98560 Matlock 114 3 $73k $526k 100%

Partly in Mason County

Residential ZIP codes mainly in another county that reach at least 1% into Mason County, by their share here
In this county
98541 Elma 10,810 55 $79k $390k 41%
98380 Seabeck 5,471 113 $125k $579k 6%
98557 McCleary 4,079 115 $79k $369k 2%

Download the 12 ZIP codes as CSV

Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates; county shares by land area (Census 2020 ZCTA-county relationship file).

Which ZIP codes cross the county line?

3 ZIP codes of Mason County extend into another county. A ZIP code follows mail routes, not county borders.

Share of each ZIP code's land in Mason County and in the neighboring counties
ZIPIn MasonElsewhere
9854141%Grays Harbor County 59%
983806%Kitsap County 94%
985572%Grays Harbor County 98%

Source: U.S. Census Bureau, 2020 ZCTA-county relationship file (shares of land area).

Which first three digits do Mason County's ZIP codes use?

The first three digits of a ZIP code name the sectional center, the mail processing plant that sorts it. Mason County's ZIP codes use 2 prefixes: 983 and 985.

Three-digit prefixes of Mason County's ZIP codes, the sectional center for each (USPS labeling list L005, effective October 1, 2026) and how many of the prefix's codes are Mason County's
PrefixSectional centerHereAll codes
983 Tacoma, WA (SCF 983) 1 81
985 Tacoma, WA (SCF 983) 11 77

Source: U.S. Postal Service, labeling list L005 (3-digit ZIP Code prefix groups, SCF sortation), effective October 1, 2026.