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zipcodes.pro — STATE/ND/COUNTY/FOSTER

Foster County, ND ZIP codes

Foster County, ND has 3 ZIP codes, in 3 towns: 58421, 58443 and 58445. 2 more cross into it from neighbouring counties: 58455 and 58464.

The county seat is Carrington.

ZIP codes
3
Partly in it
2 more
Towns
3
County seat
Carrington
County FIPS
38031
Population
3,358
Median household income
$87,831
Land area
634 sq mi

Foster County ZIP codes by town

Carrington (county seat)
58421

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 Foster County

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

Map of Foster County ZIP codes

584215844358445

The ZIP codes of Foster 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.

Foster County in numbers

About 3,358 people live in Foster County, in 1,531 households, the 32nd most populous of North Dakota's 53 counties. The median household income is $87,831 a year, 15% above the North Dakota median of $76,657 (US: $80,734). The median owner-occupied home is valued at $167,500 (33% below the North Dakota median), and median gross rent is $780 a month. The median age is 43.4; 28.5% of adults 25 and over hold a bachelor's degree or higher (32.7% across North Dakota); the average commute takes 13 minutes.

Population3,358Foster3,358
Households1,531Foster1,531
Median age43.4Foster43.4North Dakota35.9US 38.9
Median household income$87,831Foster$87,831North Dakota$76,657US $80,734
Median home value$167,500Foster$167,500North Dakota$249,900US $332,700
Median gross rent$780Foster$780North Dakota$954US $1,413
Bachelor's degree or higher28.5%Foster28.5%North Dakota32.7%US 35.7%
Mean commute12.9 minFoster12.9 minNorth Dakota17.9 minUS 26.4 min
Population density5 / sq miFoster5 / 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.

Largest towns in Foster County

Largest towns in Foster County
TownZIP codesPopulation
Carrington 1 2,168
Glenfield 1 63
Grace City 1 61

Population of the census place of that name where there is one, otherwise of the ZIP codes the Postal Service addresses by it. A town's ZIP codes can reach past the county line.

Neighbouring counties

Counties that share a ZIP code with Foster County.

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

Every ZIP code in Foster County, with figures

ZIP codes in Foster County
ZIP City Type Population Median income Median home
58421 Carrington , ND Standard 2,969 $89,097 $171,200
58443 Glenfield , ND Standard 152 $73,500 $120,800
58445 Grace City , ND Standard 145 $72,250 $109,400

Cite this page

zipcodes.pro. “Foster County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/nd/county/foster

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