59231 ZIP Code — Saint Marie, MT

Valley County, Montana

ZIP code 59231 is located in Saint Marie, Montana, within Valley County. It covers approximately 0.56 square miles and serves a population of 428 residents. This is a standard ZIP code in the Mountain (MT) timezone, served by area code 406.

About ZIP code 59231

The housing stock consists of a mix of housing types. Most homes were built in the 1960s, giving the area an established character. Median home value is $20,800. Owner-occupancy is high at 83%, well above the national average.

Median household income is $36,509. Poverty affects 38% of residents, above the national average. 71% of households receive Social Security income, suggesting a notable retiree or disability population.

The dominant occupation class is sales and office, with education and healthcare as the leading industry. Remote work is prevalent — 24% of workers work from home.

College attainment at 19% is below the national average, consistent with a trades and production-oriented local economy.

Notable community characteristics include disability rates above the national average at 31%.

Overall, ZIP code 59231 reflects a community defined by a trades-oriented workforce, economic challenges above the national average, high homeownership, a high rate of remote workers, and a significant Social Security-dependent population.

428
population
0.56
sq mi land
Standard
ZIP type
Mountain (MT)
timezone
59231 ZIP code map
Cities in ZIP code 59231

Below are the cities the US Postal Service accepts for ZIP code 59231. Using any city not on this list may result in mail delivery delays.

City Status
Saint Marie Acceptable
Demographics updated 06/2026
Population
Total population 428
Population density 764 / sq mi
State FIPS 30
County FIPS 105
Geography
Land area 0.56 sq mi
Water area 0.00 sq mi
Latitude 48.4062
Longitude -106.4877
Timezone Mountain (MT)
Area code 406
Total population by age
Gender
Race & ethnicity
Economics updated 06/2026
Household income
Income range This ZIP County avg State avg
Under $50k 56.4% 48.6% 44.2%
$50k – $100k 43.6% 35.5% 32.0%
$100k – $200k 0.0% 13.9% 19.2%
Over $200k 0.0% 2.0% 4.7%

Demographics & statistics

428
Population
764
People per sq mi
37.8
Median age
$36,509
Median household income
$15,911
Per capita income
$20,800
Median home value
$0
Median monthly rent
83.4%
Home ownership
37.6%
Poverty rate
24.1%
Unemployment
868
Housing units
18.9%
Bachelor's or higher

Age distribution

Male Female
7
5–9
12
11
10–14
19
11
20–24
18
21
25–34
37
50
35–44
88
6
45–54
11
4
55–59
7
8
65–74
14
33
75–84
57
5
85+
9
← Male
Female →

Age summary

GroupCount%
Under 184911.4%
18 and over37988.6%
65 and over12629.4%
Median age37.8 years

Race & ethnicity

White 58.2%
Two or more races 39.7%
American Indian / Alaska Native 2.1%
GroupCount%
White24958.2%
Two or more races17039.7%
American Indian / Alaska Native92.1%

Household income

Income range This ZIP County avg State avg
Under $50k 56.4% 48.6% 44.2%
$50k – $100k 43.6% 35.5% 32.0%
$100k – $200k 0.0% 13.9% 19.2%
Over $200k 0.0% 2.0% 4.7%
Under $10k 13.4%
$10k–$15k 8.9%
$15k–$25k 8.9%
$25k–$35k 7.6%
$35k–$50k 36.9%
$50k–$75k 18.5%
$75k–$100k 5.7%
Range% of households
Under $10k13.4%
$10k–$15k8.9%
$15k–$25k8.9%
$25k–$35k7.6%
$35k–$50k36.9%
$50k–$75k18.5%
$75k–$100k5.7%
Median income$36,509

Housing

Home values

Under $50k 67.2%
$50k–$100k 32.8%

Housing overview

MetricValue
Median home value$20,800
Median rent / month$0
Owner occupied83.4%
Renter occupied16.6%
Vacant82.4%
Single-family detached6.9%
Large apartment buildings0.0%
Mobile homes0.0%
Median rooms5.7
Avg household size (owned)2.33

Year built

Era%
2020 or later0.0%
2010–20190.0%
2000–20090.0%
1990–19990.0%
1980–19890.0%
1970–19791.5%
1960–196968.6%
1950–195930.0%
1940–19490.0%
1939 or earlier0.0%

Bedrooms

Size% of units
No bedroom (studio)1.0%
1 bedroom0.0%
2 bedrooms13.1%
3 bedrooms54.5%
4 bedrooms31.4%
5+ bedrooms0.0%

Vehicles per household

Vehicles% of households
No vehicle11.5%
1 vehicle41.4%
2 vehicles33.8%
3 or more13.4%

Heating fuel

Fuel type%
Utility gas86.6%
Electricity5.7%
Propane / LP gas7.6%

Households & families

Household typeCount%
Married-couple family4830.6%
Cohabiting couple31.9%
Male householder, no spouse2515.9%
Female householder, no spouse8151.6%
Households with children under 182616.6%
Households with seniors (65+)10063.7%
Average household size2.73

Marital status

StatusMaleFemale
Never married51.1%53.3%
Married38.7%19.0%
Separated0.0%0.0%
Widowed0.0%14.0%
Divorced10.2%13.6%

Education

Less than 9th grade 6.9%
Some HS, no diploma 24.3%
HS graduate 22.9%
Some college, no degree 24.6%
Associate's degree 2.6%
Bachelor's degree 18.9%
Graduate / professional 0.0%
Metric%
HS diploma or higher68.9%
Bachelor's or higher18.9%

School enrollment (ages 3–17)

TypeCount%
Nursery / preschool00.0%
Kindergarten00.0%
Elementary school4957.6%
High school00.0%
College / grad school3642.4%

Employment

Industry of employment

Education & healthcare 47.1%
Retail trade 27.1%
Arts, food & hospitality 22.4%
Public administration 3.5%

Occupation

Category%
Management, business & arts27.1%
Service25.9%
Sales & office47.1%
Natural resources & construction0.0%
Production & transportation0.0%

Employment type

Type%
Private sector72.9%
Government3.5%
Self-employed23.5%
Unpaid family workers0.0%

Commute

Method%
Drive alone72.2%
Carpool4.2%
Public transit0.0%
Walk0.0%
Work from home23.6%
Other means0.0%
Avg commute (minutes)0.0

Poverty

All people 37.6%
Under 18 years 100.0%
18 and over 29.6%
Married-couple families 54.2%
Female-led households 0.0%

Income support

Source% of households
Social Security71.3%
Retirement income54.8%
Supplemental Security4.5%
Cash public assistance0.0%
Food stamps / SNAP14.6%

Health indicators

Condition%
Obesity32.9%
High blood pressure44.1%
High cholesterol38.7%
Diabetes14.9%
Heart disease11.2%
Stroke5.1%
Asthma10.2%
Arthritis39.0%
Kidney disease4.5%
Pulmonary disease10.5%
Cancer10.6%
Behavior / access%
Smoking17.7%
Binge drinking15.4%
No physical activity25.0%
Less than 7 hrs sleep31.6%
Depression20.6%
Fair or poor health17.4%
Poor mental health11.5%
Poor physical health13.9%
No health insurance11.6%
Visited doctor (checkup)77.2%
Visited dentist60.6%
Cholesterol screening92.5%
Teeth loss15.4%

Veterans & disability

VeteransCount%
Civilian veterans123.2%
Disability%
Any disability30.8%
Under 180.0%
18–64 years33.6%
65 and over37.3%

Health insurance coverage

Type%
Private insurance61.2%
Public insurance81.1%
No insurance12.4%
Uninsured under 190.0%

Language & origin

Language spoken at home (age 5+)

LanguageCount%
English only428100.0%
Spanish00.0%
Other Indo-European00.0%
Asian & Pacific Islander00.0%
Other languages00.0%

Place of birth & citizenship

OriginCount%
Native born (US)428100.0%
Born in same state428100.0%
Born in different state9822.9%
Foreign born00.0%
Naturalized citizen00.0%
Not a US citizen00.0%

Ancestry

AncestryCount%
Polish163.7%
AncestryCount%
French71.6%

Technology access

Metric% of households
Computer access36.7%
Internet access82.8%

Source: U.S. Census Bureau, American Community Survey 2025 estimates.

Frequently asked questions about ZIP code 59231

What city is ZIP code 59231 in?

ZIP code 59231 is primarily assigned to Saint Marie, Montana.

What county is ZIP code 59231 in?

ZIP code 59231 falls within Valley County, Montana.

Does ZIP code 59231 have a large retiree population?

71% of households in ZIP code 59231 receive Social Security income, suggesting a significant retiree or disability population.

What is the poverty rate in ZIP code 59231?

38% of residents in ZIP code 59231 live below the poverty line, above the national average.

Does ZIP code 59231 have an older population?

29% of residents in ZIP code 59231 are 65 or older, above the national average of ~17%.

Is ZIP code 59231 mostly owner-occupied?

83% of occupied units in ZIP code 59231 are owner-occupied, well above the national average.

What timezone is ZIP code 59231 in?

ZIP code 59231 observes the MST timezone.

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