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zipcodes.pro — STATE/MT/COUNTY/PETROLEUM

Petroleum County, MT ZIP codes

Petroleum County, MT has 2 ZIP codes, in 2 towns: 59087 and 59084. 3 more cross into it from neighbouring counties: 59072, 59032 and 59058.

The county seat is Winnett.

ZIP codes
2
Partly in it
3 more
Towns
2
County seat
Winnett
County FIPS
30069
State
Montana
Population
447
Median household income
$60,208
Land area
1,656 sq mi

Petroleum County ZIP codes by town

Winnett (county seat)
59087

Each ZIP code is listed under the county most of its land lies in and the town the Postal Service names it for; a ZIP code's own page shows exactly how it is split.

ZIP codes partly in Petroleum County

These ZIP codes lie mostly in a neighbouring county but each cover a twentieth or more of Petroleum County.

Map of Petroleum County ZIP codes

5908459087

The ZIP codes of Petroleum County, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Petroleum County in numbers

About 447 people live in Petroleum County, in 221 households, the 56th most populous of Montana's 56 counties. The median household income is $60,208 a year, 17% below the Montana median of $72,509 (US: $80,734). The median owner-occupied home is valued at $201,400 (46% below the Montana median), and median gross rent is $800 a month. The median age is 51.6; 30.8% of adults 25 and over hold a bachelor's degree or higher (35.2% across Montana); the average commute takes 16 minutes.

Population447Petroleum447
Households221Petroleum221
Median age51.6Petroleum51.6Montana40.4US 38.9
Median household income$60,208Petroleum$60,208Montana$72,509US $80,734
Median home value$201,400Petroleum$201,400Montana$375,800US $332,700
Median gross rent$800Petroleum$800Montana$1,081US $1,413
Bachelor's degree or higher30.8%Petroleum30.8%Montana35.2%US 35.7%
Mean commute16.2 minPetroleum16.2 minMontana19.1 minUS 26.4 min
Population density0 / sq miPetroleum0 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates. Survey estimates carry margins of error, wider for small places. Sources and methods.

Neighbouring counties

Counties that share a ZIP code with Petroleum County.

Not sure you are in Petroleum County? What county am I in? answers from your location, near a county line included.

Every ZIP code in Petroleum County, with figures

ZIP codes in Petroleum County
ZIP City Type Population Median income Median home
59084 Teigen , MT No street area — — —
59087 Winnett , MT Standard 395 $62,813 $195,300

Cite this page

zipcodes.pro. “Petroleum County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/mt/county/petroleum

Underlying data is public domain or openly licensed — sources, vintages and licences.