Isanti County is a county in Minnesota, United States, about 40 miles north of downtown Minneapolis along the Rum River. It had a population of 41,135 at the 2020 census and covers 452 square miles (1,170 km2) of land and water, centred near 45°34′N 93°17′W.
Cambridge is the county seat, and its postal code is 55008. The county has four incorporated cities, thirteen townships, one census-designated place, and about two dozen unincorporated communities. It runs on Central time and is part of the Minneapolis–St. Paul–Bloomington metropolitan area.
Towns & Villages in Isanti County
Isanti County’s settlements split into four cities, thirteen civil townships, one census-designated place (Stanchfield), and roughly two dozen smaller unincorporated communities and former rail sidings scattered through the townships. Most of the smaller names below are township hamlets rather than standalone towns — several no longer have a population count of their own.
| Place | Type | Township | Pop. | ZIP |
|---|---|---|---|---|
| Cambridge | City · seat | Cambridge Township | 9,478 | 55008 |
| Isanti | City | Isanti Township | 6,442 | 55040 |
| Braham | City | — | 1,915 | 55006 |
| St. Francis | City | — | 8,024 | 55070 |
| Stanchfield | CDP | Stanchfield Township | — | 55080 |
| Andree | Unincorp. | Athens Township | — | — |
| Athens | Unincorp. | Athens Township | — | — |
| Blomford | Unincorp. | Maple Ridge Township | — | — |
| Bradford | Unincorp. | Bradford Township | — | — |
| Carmody | Unincorp. | North Branch Township | — | — |
| Crown | Unincorp. | Stanford Township | — | — |
| Dalbo | Unincorp. | Dalbo Township | — | — |
| Day | Unincorp. | Oxford Township | — | — |
| Edgewood | Unincorp. | Springvale Township | — | — |
| Elm Park | Unincorp. | Bradford Township | — | — |
| Grandy | Unincorp. | Cambridge Township | — | — |
| Oxlip | Unincorp. | Oxford Township | — | — |
| Pine Brook | Unincorp. | Spencer Brook Township | — | — |
| Spencer Brook | Unincorp. | Spencer Brook Township | — | — |
| Spring Lake | Unincorp. | Springvale Township | — | — |
| Springvale | Unincorp. | Springvale Township | — | — |
| Stanchfield Corner | Unincorp. | Stanchfield Township | — | — |
| Stanford | Unincorp. | Stanford Township | — | — |
| Stanley | Unincorp. | Stanford Township | — | — |
| Walbo | Unincorp. | Wyanett Township | — | — |
| Weber | Unincorp. | North Branch Township | — | — |
| West Point | Unincorp. | Wyanett Township | — | — |
| Wyanett | Unincorp. | Wyanett Township | — | — |
Bodum, once listed on old maps in the county’s north, is a ghost town with no remaining population. Braham sits partly across the line in Kanabec County and St. Francis partly across the line in Anoka County, so both cities’ full populations are shared with a neighbor.
Townships
| Township | Pop. (2020) | Main settlements |
|---|---|---|
| Cambridge Township | — | surrounds the city of Cambridge, Grandy |
| Isanti Township | — | surrounds the city of Isanti |
| Athens Township | — | Athens, Andree |
| Bradford Township | — | Bradford, Elm Park |
| Dalbo Township | — | Dalbo |
| Maple Ridge Township | — | Blomford |
| North Branch Township | — | Carmody, Weber |
| Oxford Township | — | Oxlip, Day |
| Spencer Brook Township | — | Spencer Brook, Pine Brook |
| Springvale Township | — | Springvale, Spring Lake, Edgewood |
| Stanchfield Township | — | Stanchfield (CDP), Stanchfield Corner |
| Stanford Township | — | Stanford, Stanley, Crown |
| Wyanett Township | — | Wyanett, Walbo, West Point |
Isanti County’s population figures are not broken out by individual township in the sources used for this page, so township population cells are left blank rather than guessed.
ZIP Codes
- 55008 — Cambridge (also serves Grandy and Cambridge Township)
- 55040 — Isanti (also serves Athens and Andree)
- 55006 — Braham (also serves parts of Bradford Township)
- 55070 — St. Francis (shared with neighboring Anoka County)
- 55080 — Stanchfield
Smaller unincorporated places such as Dalbo, Wyanett, Oxlip and Spencer Brook are served by the nearest post-office ZIP above rather than having a code of their own.
Geography
Isanti County sits in east-central Minnesota, where the terrain is hilly, cut by drainages and gullies, and dotted with lakes and ponds; its highest point is roughly 1,020 feet above sea level near the northwest corner. The Rum River runs south through the middle of the county on its way to the Mississippi. Of the county’s 452 square miles, 436 are land and 16 are water.
Isanti County borders Anoka County to the south, and shares lines with Sherburne County to the southwest, Mille Lacs County to the northwest, Kanabec County to the north, Pine County to the northeast, and Chisago County to the east.
Demographics
The 2020 census counted 41,135 residents of Isanti County. Cambridge (9,478) and St. Francis (8,024) are the two largest communities, followed by Isanti (6,442). The county’s median household income runs below the Minnesota median of $85,086, reflecting its mix of small-town and rural households outside the immediate Twin Cities job market. Density works out to roughly 94 people per square mile of land.
Economy & Local Life
Isanti County is part of the Minneapolis–St. Paul–Bloomington metropolitan statistical area, and many residents commute toward the Twin Cities for work. Locally, agriculture, small manufacturing, retail and healthcare anchor the economy along the U.S. Highway 65 corridor through Cambridge and Isanti. The county was legally dry until 1965, when the local option to ban alcohol sales was eliminated — a detail still noted in local histories.
History
Isanti County was organized on February 13, 1857. Its name comes from the Dakota word for “knife,” an old term applied to the Santee (Isanti) division of the Dakota people who once lived along the Rum River. Early settlement followed logging and the river trade, and the county’s townships were platted through the late 1850s and 1860s as farming communities spread out from Cambridge.
Getting There
U.S. Highway 65 runs north–south through Cambridge and Isanti, connecting the county directly to the Twin Cities. State Highway 47 and State Highway 95 cross the county east–west.
- Minneapolis — 40 miles south
- St. Paul — 45 miles south
- Duluth — 100 miles northeast
- St. Cloud — 35 miles west
The nearest commercial airport is Minneapolis–St. Paul International Airport, about an hour’s drive south.
Frequently Asked Questions
Where is Isanti County?
It is in east-central Minnesota, roughly 40 miles north of downtown Minneapolis along the Rum River.
What is the population of Isanti County?
41,135 people, per the 2020 census.
How big is Isanti County?
452 square miles (1,170 km2), of which 436 square miles are land.
What is the county seat of Isanti County?
Cambridge, Minnesota.
How many towns are in Isanti County?
Four incorporated cities — Cambridge, Isanti, Braham and St. Francis — plus thirteen townships and about two dozen smaller unincorporated communities.
What ZIP codes are in Isanti County?
The main ZIP codes are 55008 (Cambridge), 55040 (Isanti), 55006 (Braham), 55070 (St. Francis) and 55080 (Stanchfield).
Where does the county’s name come from?
From the Dakota word for “knife,” an old name for the Santee (Isanti) Dakota people who lived along the Rum River.
More counties in this state: Towns and villages in Minnesota.