Marathon County, Wisconsin

Marathon County is a county in Wisconsin, United States, centred on the city of Wausau, about 140 miles northwest of Milwaukee. It had a population of 138,013 at the 2020 census, an estimated 138,400 by 2024, and covers 1,576 square miles (4,080 km2) centred near 44°54′N 89°46′W — the largest county by land area in Wisconsin.

Wausau is the county seat; its postal code is 54401. The county holds 6 cities, 16 incorporated villages and 39 towns, plus dozens of smaller unincorporated communities inside those towns, and it runs on Central Time. Its FIPS code is 55073.

Towns & Villages in Marathon County

Marathon County has 22 incorporated cities and villages on record: 6 cities and 16 villages. In Wisconsin, cities and villages are independent of the town system, so no township column applies to them — each sits on its own, detached from the surrounding civil towns. Six of the places below straddle a county line; the population figure given is the community’s full census total, not just its Marathon County share.

Six places on this list are shared with a neighbor: Marshfield’s 18,929 residents are overwhelmingly a Wood County total, with only 810 in Marathon County; Abbotsford (610 of 2,275) and Colby (677 of 1,952) and Dorchester (3 of 849) sit mostly or largely in Clark County; Unity splits closer to even (233 in Marathon, 151 in Clark); and Birnamwood is almost entirely a Shawano County village, with just 14 residents on the Marathon side. Kronenwetter and Mosinee share the single ZIP code 54455 rather than each holding a separate one.

Towns

Wisconsin uses “towns” as its township-equivalent civil divisions, and Marathon County has 39 of them — more than all but a handful of counties in the state. A town usually takes the name of its oldest or largest settlement, though many hold no separately incorporated place at all; the sourced matches below are noted, the rest are open countryside and farmland with a town hall and little else.

ZIP Codes

• 54401 — Wausau (also serves 54403, a Wausau-area ZIP)
• 54455 — shared by Mosinee and Kronenwetter
• 54474 — Rothschild
• 54440 — Hatley
• 54411 — Athens

Weston, Rib Mountain, Schofield, Colby, Spencer, Stratford, Marathon City, Edgar, Elderon and Fenwood do not have a ZIP confirmed in the sources checked for this page; mail to those villages is handled under a neighboring town’s code, most often Wausau’s or Mosinee’s.

Geography

Marathon County sits in north-central Wisconsin, a landscape of rolling farmland in the south giving way to forest in the north. Of its 1,576 square miles, 1,545 are land and 31 are water, roughly 2 percent — the county has no single large natural lake, and its main waterway is the Wisconsin River, which runs south through Wausau, Rothschild and Mosinee on its way toward the Mississippi. Rib Mountain, a quartzite ridge rising above the Wisconsin River near Wausau, is the county’s best-known landform and the site of a state park and ski area.

Lincoln County lies to the north, Langlade County to the northeast, Shawano County to the east, Waupaca County to the southeast, Portage County to the south, Wood County to the southwest, Clark County to the west, and Taylor County to the northwest. Lincoln County, Langlade County, Shawano County, Waupaca County, Portage County, Wood County, Clark County and Taylor County all border Marathon directly.

Demographics

Marathon County had a population of 138,013 at the 2020 census, and the latest estimate puts the county near 138,400 residents. Wausau and Weston are by far the two largest communities, together holding well over a third of the county’s population. Median household income runs $77,884 (2024), somewhat higher than Wisconsin’s statewide figure of $74,631 (2023). Population density works out to roughly 89 people per square mile of land, low for a county anchored by a metro area the size of Wausau, reflecting how much of Marathon County outside its cities and villages is farmland and forest.

Economy & Local Life

Manufacturing employs the most workers in the county, about 14,930 people, followed by health care and social assistance at 12,557 and retail trade at 7,105. Wausau’s economy runs close to a third manufacturing, spanning paper mills, insurance and home manufacturing, and the county is also a center of American ginseng cultivation and red granite quarrying. Marshfield Clinic Health System and Aspirus Health, both headquartered in the region, are major regional health care employers. Wausau is also home to Employers Insurance of Wausau (now part of Liberty Mutual), a company that grew alongside the city’s lumber-era economy in the early 1900s. The county’s biggest annual event is the Wisconsin Valley Fair at Marathon Park in Wausau each August, alongside the Big Bull Falls Blues Festival the same month.

History

Wisconsin’s territorial legislature organized Marathon County in 1850, carving it out of Portage County; at its founding, the county’s boundaries reached all the way north to the Michigan border. It was named for the battlefield at Marathon, Greece. Wausau itself traces to 1839, when the site was known by the Ojibwe name “waasa,” meaning a faraway place; George Stevens began logging the surrounding pine forest and built a sawmill there in 1840, and other mill operators followed along the Wisconsin River. Wausau was incorporated as a village in 1861 and chartered as a city in 1872, the year August Kickbusch became its first mayor. The railroad reached Wausau in 1874. German immigration after the failed 1848 revolutions in Europe shaped the county heavily — the 2000 census found 52.6 percent of residents claimed German ancestry and 13.6 percent Polish. By 1906 the old-growth pine was gone, but Wausau had already diversified into paper manufacturing and insurance, and the county’s economy survived the lumber era’s end.

Getting There

Interstate 39 runs north-south through the county along the Wisconsin River corridor, and US Route 51 parallels it through Wausau, Rothschild and Mosinee.

• Stevens Point — about 30 miles south
• Green Bay — about 90 miles east
• Eau Claire — about 90 miles west
• Madison — about 160 miles south

Central Wisconsin Airport, in Mosinee about ten miles south of Wausau, is the county’s commercial airport, with regional jet service to Chicago O’Hare and Minneapolis-St. Paul. There is no Amtrak service in the county; the nearest station is well outside the region, so most long-distance travelers connect through one of the two served airports or drive to Madison or Milwaukee.

Frequently Asked Questions

Where is Marathon County located?
It sits in north-central Wisconsin along the Wisconsin River, bordered by Lincoln, Langlade, Shawano, Waupaca, Portage, Wood, Clark and Taylor counties.

What is the population of Marathon County?
138,013 at the 2020 census, with an estimate near 138,400 by 2024.

How big is Marathon County?
1,576 square miles (4,080 km2), of which 1,545 square miles are land — the largest county by land area in Wisconsin.

What is the county seat of Marathon County?
Wausau, the county’s largest city since the 1870s, is the county seat.

How many towns and villages are in Marathon County?
6 cities and 16 villages are incorporated, plus 39 towns, the state’s township-equivalent civil divisions.

What ZIP codes does Marathon County use?
54401 for Wausau, 54455 for Mosinee and Kronenwetter, 54474 for Rothschild, 54440 for Hatley and 54411 for Athens, among others.

What is Marathon County known for?
American ginseng cultivation, red granite quarrying, Rib Mountain State Park, and Wausau’s 19th-century lumber and paper industry.

More counties in this state: Towns and villages in Wisconsin.