Minidoka County area

Minidoka County, Idaho covers 762.4 square miles: 757.2 square miles of land and 5.147 square miles of water. Its county seat is Rupert. An estimated 22,911 people lived there in 2025.

Official Census measurements · GEOID 160672026 Gazetteer · retrieved September 27, 2026
Land area757.2 mi²
Water area5.147 mi²
Population (2025)22,911
People per mi²30

County outline

Generalized outline of Minidoka County, Idaho
2025 Census cartographic boundary, fitted to this frame. County maps are not at a common scale. The 2026 area measurements below come from the separate Gazetteer release. Map source and limitations.

Where Minidoka County is located

Minidoka County highlighted on a map of all U.S. county equivalents. About the maps

Area breakdown

Land accounts for 99.3% of Minidoka County’s measured area and water for 0.7%. Its combined area converts to 1,974.5 square kilometers or approximately 487,919 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land757.2271,961.209484,625.3
Water5.14713.3313,294.1
Total762.3741,974.54487,919.4

How Minidoka County compares

By original Census land area, Minidoka County ranks #35 of 44 in Idaho and #1162 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 0.576 times the Idaho county-equivalent median of 1,315.7 square miles. It accounts for 0.9% of the combined county land area in the state.

See the complete Idaho ranking · What counts as a county equivalent?

Population and density of Minidoka County

The Census Bureau estimates that 22,911 people lived in Minidoka County on July 1, 2025. That ranks #1,737 of 3,222 county equivalents nationally and #18 of 44 in Idaho. Since the April 1, 2020 estimates base of 21,584, the population has grown by 1,327 (+6.1%), compared with +10.4% for Idaho as a whole.

With 757.2 square miles of land, that is 30 people per square mile (12 per km²), placing Minidoka County #2,000 nationally for density and #15 in Idaho. The median county equivalent has 47 people per square mile; the Idaho median is 10. Put another way, there are about 21 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate21,66921,95122,21422,62122,72722,911
Change—+282+263+407+106+184

U.S. Census Bureau, Vintage 2025 population estimates. Estimates are revised each year and are not decennial census counts. Density divides the whole population by the whole county’s land area, so it describes an average, not how settlement is distributed within the county. Population sources and methods.

Cities and towns in Minidoka County

6 incorporated places lie at least partly in Minidoka County. Together they are home to 12,550 people (54.8%); the other 10,361 (45.2%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Rupert city, with 6,460 residents in the county. By land, Burley city is the largest at 6.921 mi² across all its counties. Among places with at least 1,000 residents in 2020, Paul city grew fastest since then (+44.3%).

Incorporated placePopulation 2025Since 2020Land mi²
Rupert cityCounty seat6,460+7%2.059
Heyburn city3,783+3.4%2.592
Paul city1,722+44.3%0.742
Burley cityAlso in 1 other county356+1.4%6.921
Acequia city134+3.9%0.534
Minidoka city95+2.2%0.295

Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Minidoka County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.

Metropolitan area

Minidoka County is a central county of the Burley, ID Micropolitan Statistical Area. Its 2 county equivalents have 49,308 residents on 3,322.8 square miles of land; Minidoka County accounts for 22.8% of the land and 46.5% of the residents. By combined land it ranks #42 of 542 micropolitan areas, and #230 by population.

County equivalentPopulation 2025Land mi²
Cassia County26,3972,565.6
Minidoka County22,911757.2

ZIP codes

5 ZIP Code Tabulation Areas have land in Minidoka County; 2 of them have most of their land inside the county, and the others mainly cover neighboring areas.

8331883335833368334783350

ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Lighter codes have less than half of their land in this county. Post-office-box and single-address ZIP Codes have no tabulation area.

Counties bordering Minidoka County

Minidoka County shares a land border with 4 county equivalents. It has more land than 1 of them. The largest neighbor is Blaine County (2,637.7 mi²) and the smallest is Jerome County (597.5 mi²). Together with its neighbors, Minidoka County forms a block of 7,759.5 mi² of land, of which it holds 9.8%.

Map of Minidoka County and the 4 county equivalents that border it Blaine County, Idaho: 2,637.7 mi² landLincoln County, Idaho: 1,201.4 mi² landCassia County, Idaho: 2,565.6 mi² landJerome County, Idaho: 597.5 mi² land
Minidoka County (dark) and its bordering county equivalents. Select a neighbor to open its profile. Drawn from the 2025 Census cartographic boundaries in an equal-area projection. How borders are determined.
Bordering county equivalentLand mi²Size vs. MinidokaCompare
Blaine County2,637.73.5× largerCompare
Cassia County2,565.63.4× largerCompare
Lincoln County1,201.41.6× largerCompare
Jerome County597.51.3× smallerCompare

How big is Minidoka County compared with U.S. states?

Minidoka County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.4 times as much. Idaho’s county land could hold about 109 areas the size of Minidoka County.

Land area: Minidoka County and the closest-sized states
Minidoka County757.2 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 27.5 miles (44.3 km) on each side. Real county shapes are rarely square, so this is a scale reference rather than a width or driving distance.

State figures are the sums of each state’s county-equivalent land measurements in the same Census release, so states and counties are compared on the same basis. Published state totals can differ slightly because of rounding. Compare all states · Counties bigger than entire states.

What stands out about Minidoka County?

Minidoka County has more land than 2,060 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Minidoka County757.2 mi²
Idaho median1,315.7 mi²
National median604.5 mi²

A median is the middle county-equivalent measurement, not the average of the largest and smallest. All three bars use the same linear scale. Very small areas may appear as a thin sliver; the labels retain their values.

Does including water change its rank?

Using land plus water places Minidoka County at #1,262 nationally by total area, 100 places farther from the top than its land rank. Other county equivalents gain more area when their water measurements are included.

Its water share is 0.7%, compared with a national county-equivalent median of 1.2% — 0.5 percentage points lower. This describes the statistical geography’s land/water mix, not flood exposure or developable land.

Closest positions in the national land ranking

These entries sit immediately beside Minidoka County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#1161Richland County, South Carolina757.3Compare
#1162Minidoka County, Idaho757.2This county
#1163Goodhue County, Minnesota756.7Compare

Calculated from the same Census release as the area table. Total-area order uses original ALAND + AWATER; water shares and chart labels use published square miles. Calculation details.

Representative coordinates

The Census internal point is 42.857211, -113.639840. It represents a location inside the geography; it is not necessarily the centroid or the address of a courthouse.

Source and precision

U.S. Census Bureau, 2026 Gazetteer Files, Counties. Original ALAND: 1,961,208,085 m²; AWATER: 13,330,815 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.

Download the official county source ZIP ↗ · Methodology

Common questions

How big is Minidoka County?

Minidoka County, Idaho has 757.2 square miles (1,961.2 km²) of land and 5.147 square miles of water, for a total area of 762.4 square miles. It ranks #1162 of 3,222 U.S. county equivalents by land area.

Is Minidoka County the largest county in Idaho?

No. Minidoka County ranks #35 of 44 in Idaho by land area. The largest is Idaho County, with 8,477.5 square miles of land.

What counties border Minidoka County?

Minidoka County shares a land border with Blaine County, Lincoln County, Cassia County, and Jerome County.

What is the population of Minidoka County?

The Census Bureau estimates Minidoka County had 22,911 residents on July 1, 2025, ranking #1,737 of 3,222 county equivalents. That is 30 people per square mile of land.

What is the county seat of Minidoka County?

The county seat of Minidoka County is Rupert.

What cities and towns are in Minidoka County?

Minidoka County has 6 incorporated places. The most populous five are Rupert city, Heyburn city, Paul city, Burley city, and Acequia city; 10,361 residents live outside any incorporated place.

Is Minidoka County part of a metropolitan area?

Yes. It is a central county of the Burley, ID Micropolitan Statistical Area, which has 2 county equivalents and 49,308 residents.

How many ZIP codes are in Minidoka County?

5 ZIP Code Tabulation Areas have land in Minidoka County, and 2 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

How does Minidoka County compare with U.S. states?

It has less land than every state. Rhode Island, the smallest, has 1.4 times as much land.

How many acres of land are in Minidoka County?

The land measurement converts to approximately 484,625 acres. Including water, total area is approximately 487,919 acres. One square mile equals 640 acres.

Why might another source show a different area?

Check whether it reports land or total area, its Census vintage, and its rounding. Our guide explains how to reconcile county area figures.

Can this establish a property boundary?

No. Statistical measurements and generalized maps do not establish property lines. Consult the relevant local surveying or land-records authority.

Cite this county

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