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County ZIP codes · Montana · FIPS 30047

Lake County, MT ZIP Codes

Lake County, Montana has 15 ZIP codes (Census 2020 ZCTA-county file; GeoNames postal codes, October 2026), all residential. 12 of the residential ones lie mainly in Lake County and 3 mainly in a neighboring county; 4 cross the county line. Median household income ranges from $31,970 in 59845 (Hot Springs) to $83,019 in 59911 (Bigfork) (Census Bureau, ACS 2020-2024).

  • ACS2020-24
  • Census2020

Where are the ZIP codes of Lake County?

59821 · Arlee: $67k59824 · Charlo: $53k59845 · Hot Springs: $32k59855 · Pablo: $33k59860 · Polson: $62k59863 · Ravalli: $79k59864 · Ronan: $62k59865 · Saint Ignatius: $57k59910 · Big Arm: $100k59911 · Bigfork: $83k59914 · Dayton: $84k59915 · Elmo: $59k59922 · Lakeside: $87k59929 · Proctor: $101k59931 · Rollins: $112k5984559911598605982159864598655982459910599155992259929599315991459821 · Arlee: $67k59824 · Charlo: $53k59845 · Hot Springs: $32k59855 · Pablo: $33k59860 · Polson: $62k59863 · Ravalli: $79k59864 · Ronan: $62k59865 · Saint Ignatius: $57k59910 · Big Arm: $100k59911 · Bigfork: $83k59914 · Dayton: $84k59915 · Elmo: $59k59922 · Lakeside: $87k59929 · Proctor: $101k59931 · Rollins: $112k598455991159860598215986459865598245991059922599295991459821 · Arlee: $67k59824 · Charlo: $53k59845 · Hot Springs: $32k59855 · Pablo: $33k59860 · Polson: $62k59863 · Ravalli: $79k59864 · Ronan: $62k59865 · Saint Ignatius: $57k59910 · Big Arm: $100k59911 · Bigfork: $83k59914 · Dayton: $84k59915 · Elmo: $59k59922 · Lakeside: $87k59929 · Proctor: $101k59931 · Rollins: $112k59845599115986059821598645986559824599105992259929
The residential ZIP codes of Lake 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 $53,382 and $62,047.

They carry 15 postal town names.

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

All 15 residential ZIP codes in Lake County

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

Residential ZIP codes mainly in Lake County, largest first; "In this county" is the share of the ZIP's land in the county
In this county
59860 Polson 11,897 45 $62k $442k 100%
59911 Bigfork 9,493 19 $83k $666k 86%
59864 Ronan 7,301 39 $62k $298k 100%
59865 Saint Ignatius 3,635 22 $57k $345k 100%
59824 Charlo 1,526 16 $53k $318k 100%
59910 Big Arm 692 36 $100k $589k 100%
59915 Elmo 452 8 $59k – 100%
59855 Pablo 419 1,187 $33k $161k 100%
59914 Dayton 345 31 $84k $1.21M 100%
59931 Rollins 335 12 $112k $743k 100%
59929 Proctor 230 6 $101k – 100%
59863 Ravalli 146 19 $79k – 100%

Partly in Lake County

Residential ZIP codes mainly in another county that reach at least 1% into Lake County, by their share here
In this county
59821 Arlee 2,994 9 $67k $375k 37%
59845 Hot Springs 1,223 3 $32k $191k 17%
59922 Lakeside 2,337 61 $87k $658k 10%

Download the 15 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?

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

Share of each ZIP code's land in Lake County and in the neighboring counties
ZIPIn LakeElsewhere
5991186%Flathead County 14%
5982137%Missoula County 44%; Sanders County 19%
5992210%Flathead County 90%
5984517%Sanders County 67%; Flathead County 16%

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

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

The first three digits of a ZIP code name the sectional center, the mail processing plant that sorts it. Lake County's ZIP codes use 2 prefixes: 598 and 599.

Three-digit prefixes of Lake 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 Lake County's
PrefixSectional centerHereAll codes
598 Missoula, MT (SCF 598) 8 53
599 Missoula, MT (SCF 598) 7 30

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