ZIP Codes of Lewis And Clark County, MT

Population & People
Population & People
Total Population
73,928
Household Income
Household Income
Median Income
$73,433
Housing
Housing
Total Housing Units
34,145
Business & Economy
Business & Economy
Total Businesses
2,607
Employment
Employment
Employment Rate
61.42%
Education
Education
Bachelor's Degree+
43.50%
Source: U.S. Census ACS 2024 5-Year Estimates · rolled up across the 15 ZIPs in this county.
Data Last Updated: June 1, 2026
ZIP Codes:15 ZIP Codes (8 Standard, 5 PO Box, 2 Unique) [See All]
Area Code:406
Timezone:Mountain (GMT -07:00)
Local Time:2:12:53 PM
Population:73,928 [See All]
FIPS:30049
CBSA:Helena, MT
Land Area:3,668 sq mi
Water Area:41 sq mi
Coordinates:46.7556, -112.1629
Quick Link:
https://www.zip-codes.com/county/mt-lewis-and-clark.asp
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Extreme geographic sprawl
The largest ZIP spans 27936× the smallest by area — 720.8 sq mi down to 0.03.
Among Montana's 5 most-educated counties
43.5% with bachelor's+ (#3 statewide).
Among Montana's 10 most populous counties
#6 of 56 counties with 73,928 residents.

Standout ZIPs in this County


Most Populous
Helena · 31,728 people
42.9% of county total
Highest Income
Helena · $92,985 median
1.3× county average
Largest Land Area
Augusta · 1,170.9 sq mi
Spans the most ground
Fastest Growth
Helena · 21.2% (10-yr)
25,380 → 30,754 residents
Most Educated
Helena · 50.9% bachelor's+
11,748 of 23,060 adults 25+

Things worth knowing about Lewis And Clark County


73,928 residents live across 15 ZIPs covering 3,668 sq mi, served by 8 distinct USPS-recognized cities.

Population moved from 65,079 to 73,265 from 2014 to 2024 — a +12.6% change. 7 ZIPs gained residents, 2 lost.

The county's wealthiest ZIP 59602 (Helena, $92,985 median) and poorest ZIP 59410 (Augusta, $42,321) are 69.9 miles apart — a 2.2× income gap across local geography.

Median home values vary 1.6× across this county — from $259,400 in 59410 (Augusta) to $408,600 in 59602 (Helena).

Density varies 16737× across the county — from 0 people/sq mi in 59410 (Augusta) to 7,433 in 59625 (Helena).

Most of the decade's growth concentrated around Helena — top growth ZIPs averaged +12.9% over the past ten years ( 59602 , 59635 and 59601 ).

Educational attainment ranges from 21.6% bachelor's+ in 59648 (Wolf Creek) to 50.9% in 59601 (Helena) — the breadth of educational profiles across the area.

Within Montana, this is the #6 most populous of 56 counties and ranks #16 for median household income with the #11 fastest decade growth .

Hosts 2 single-entity Unique ZIPs: 59625Carroll College ; and 59623City County Building .

Weighted by population, the typical household earns about $81,913 across the county — reflecting what a typical resident sees, not a simple ZIP average.

43.5% of adults age 25+ hold a bachelor's degree or higher (23,003 of 52,885 reporting). The most-educated ZIPs cluster around Helena.

8 Standard delivery, 5 PO Box only, 2 single-entity Unique ZIPs serve this county.

Stories about Lewis And Clark County


Big & sparse

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.

Total area
3,668
square miles
Avg density
20.2
people per sq mi
Population
73,928
across 15 ZIPs
Augusta
1,170.9 sq mi
520 residents
Lincoln
720.8 sq mi
1,021 residents
Helena
655.3 sq mi
30,754 residents

All ZIP Codes in Lewis And Clark County


ZIPCityTypePopulationMedian IncomeArea (sq mi)10-yr Growth
59601HelenaStandard31,728$72,290160.37.7%
59602HelenaStandard30,754$92,985655.321.2%
59635East HelenaStandard8,292$83,740109.49.8%
59639LincolnStandard1,021$57,778720.8-10.4%
59625HelenaUnique6630.1
59410AugustaPO Box520$42,3211,170.9-24.2%
59648Wolf CreekStandard486$65,750626.01.9%
59633Canyon CreekStandard272180.80.7%
59640MarysvilleStandard160$99,16741.240.4%
59636Fort HarrisonPO Box323.3220.0%
59623HelenaUnique00.0
59624HelenaPO Box0.0
59626HelenaStandard0.0
59604HelenaPO Box0.0
59620HelenaPO Box0.0

Adjacent & Nearby Counties