Isanti County area

Isanti County, Minnesota covers 451.7 square miles: 435.8 square miles of land and 15.9 square miles of water. Its county seat is Cambridge. An estimated 44,386 people lived there in 2025.

Official Census measurements · GEOID 270592026 Gazetteer · retrieved September 27, 2026
Land area435.8 mi²
Water area15.9 mi²
Population (2025)44,386
People per mi²102

County outline

Generalized outline of Isanti County, Minnesota
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 Isanti County is located

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

Area breakdown

Land accounts for 96.5% of Isanti County’s measured area and water for 3.5%. Its combined area converts to 1,169.9 square kilometers or approximately 289,082 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land435.7811,128.668278,899.8
Water15.90941.20410,181.8
Total451.691,169.872289,081.6

How Isanti County compares

By original Census land area, Isanti County ranks #75 of 87 in Minnesota and #2324 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 0.646 times the Minnesota county-equivalent median of 674.6 square miles. It accounts for 0.5% of the combined county land area in the state.

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

Population and density of Isanti County

The Census Bureau estimates that 44,386 people lived in Isanti County on July 1, 2025. That ranks #1,128 of 3,222 county equivalents nationally and #24 of 87 in Minnesota. Since the April 1, 2020 estimates base of 41,128, the population has grown by 3,258 (+7.9%), compared with +2.2% for Minnesota as a whole.

With 435.8 square miles of land, that is 102 people per square mile (39 per km²), placing Isanti County #974 nationally for density and #15 in Minnesota. The median county equivalent has 47 people per square mile; the Minnesota median is 27. Put another way, there are about 6.3 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate41,38541,95542,70943,19843,65744,386
Change—+570+754+489+459+729

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 Isanti County

Isanti County is divided into 17 municipalities and townships. In Minnesota, county subdivisions are local governments, and together they cover all of the county’s land and residents.

The most populous is Cambridge city, with 11,090 residents (25% of the county). The largest by land is Stanford township, at 38.3 mi², or 8.8% of the county’s land. Among those with at least 1,000 residents in 2020, Cambridge city grew fastest since then (+15.4%).

County subdivisionPopulation 2025Since 2020Land mi²Share of county land
Cambridge cityCounty seat11,090+15.4%7.481.7%
Isanti city7,714+13%5.0921.2%
Bradford township3,549+4%34.27.8%
Cambridge townshipCounty seat2,592+3.9%29.36.7%
Stanford township2,389+4%38.38.8%
Isanti township2,350+3.9%276.2%
Athens township2,175+3.4%30.87.1%
Wyanett township1,830+3.8%33.17.6%
Braham city1,789+0.2%1.5230.3%
North Branch township1,782+3.8%34.57.9%
Spencer Brook township1,734+4%33.77.7%
Springvale township1,626+4%34.37.9%
Stanchfield township1,198+4%33.37.7%
Oxford township1,019+4%22.55.2%
Dalbo township808+3.9%35.48.1%
Show the other 2 subdivisions
NamePopulation 2025Since 2020Land mi²
Maple Ridge township741+3.6%35
St. Francis city0—0.315

Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each subdivision inside Isanti County. Land: 2026 Census Gazetteer. How communities are listed.

Metropolitan area

Isanti County is an outlying county of the Minneapolis-St. Paul-Bloomington, MN-WI Metropolitan Statistical Area. Its 15 county equivalents have 3,790,295 residents on 7,047.6 square miles of land; Isanti County accounts for 6.2% of the land and 1.2% of the residents. By combined land it ranks #26 of 393 metropolitan areas, and #16 by population. It belongs to the Minneapolis-St. Paul, MN-WI Combined Statistical Area.

County equivalentPopulation 2025Land mi²
Hennepin County1,284,784554
Ramsey County541,623152.3
Dakota County457,710562.6
Anoka County381,605422
Washington County286,895384.8
Scott County159,017356.1
Wright County157,559661.2
Carver County114,379353.9
Sherburne County104,194432.9
St. Croix CountyWisconsin98,276722.2
Chisago County59,142414.9
Isanti County44,386435.8
Pierce CountyWisconsin43,519574
Le Sueur County29,453448.8
Mille Lacs County27,753572.3

ZIP codes

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

55006550085501755029550405505655070550795508055371553985635356358

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 Isanti County

Isanti County shares a land border with 5 county equivalents. It has more land than 3 of them. The largest neighbor is Mille Lacs County (572.3 mi²) and the smallest is Chisago County (414.9 mi²). Together with its neighbors, Isanti County forms a block of 2,799.5 mi² of land, of which it holds 15.6%.

Map of Isanti County and the 5 county equivalents that border it Chisago County, Minnesota: 414.9 mi² landAnoka County, Minnesota: 422 mi² landKanabec County, Minnesota: 521.6 mi² landMille Lacs County, Minnesota: 572.3 mi² landSherburne County, Minnesota: 432.9 mi² land
Isanti 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. IsantiCompare
Mille Lacs County572.31.3× largerCompare
Kanabec County521.61.2× largerCompare
Sherburne County432.9about the sameCompare
Anoka County422about the sameCompare
Chisago County414.91.1× smallerCompare

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

Isanti County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 2.4 times as much. Minnesota’s county land could hold about 183 areas the size of Isanti County.

Land area: Isanti County and the closest-sized states
Isanti County435.8 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 20.9 miles (33.6 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 Isanti County?

Isanti County has more land than 898 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Isanti County435.8 mi²
Minnesota median674.6 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 Isanti County at #2,340 nationally by total area, 16 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 3.5%, compared with a national county-equivalent median of 1.2% — 2.4 percentage points higher. 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 Isanti County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#2323Cocke County, Tennessee436.1Compare
#2324Isanti County, Minnesota435.8This county
#2325Davison County, South Dakota435.6Compare

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 45.562431, -93.296339. 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: 1,128,667,926 m²; AWATER: 41,203,723 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 Isanti County?

Isanti County, Minnesota has 435.8 square miles (1,128.7 km²) of land and 15.9 square miles of water, for a total area of 451.7 square miles. It ranks #2324 of 3,222 U.S. county equivalents by land area.

Is Isanti County the largest county in Minnesota?

No. Isanti County ranks #75 of 87 in Minnesota by land area. The largest is St. Louis County, with 6,248.1 square miles of land.

What counties border Isanti County?

Isanti County shares a land border with Chisago County, Anoka County, Kanabec County, Mille Lacs County, and Sherburne County.

What is the population of Isanti County?

The Census Bureau estimates Isanti County had 44,386 residents on July 1, 2025, ranking #1,128 of 3,222 county equivalents. That is 102 people per square mile of land.

What is the county seat of Isanti County?

The county seat of Isanti County is Cambridge.

What cities and towns are in Isanti County?

Isanti County has 17 county subdivisions (cities, towns and townships). The most populous five are Cambridge city, Isanti city, Bradford township, Cambridge township, and Stanford township.

Is Isanti County part of a metropolitan area?

Yes. It is an outlying county of the Minneapolis-St. Paul-Bloomington, MN-WI Metropolitan Statistical Area, which has 15 county equivalents and 3,790,295 residents.

How many ZIP codes are in Isanti County?

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

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

It has less land than every state. Rhode Island, the smallest, has 2.4 times as much land.

How many acres of land are in Isanti County?

The land measurement converts to approximately 278,900 acres. Including water, total area is approximately 289,082 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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