Madison County is a county in Montana, United States, home to the Madison River valley and the Ruby Range. It had a population of 8,623 at the 2020 census and covers 3,603 square miles (9,330 km2), of which 3,587 square miles (9,290 km2) is land, centred near 45°18′N 111°55′W.
Virginia City is the county seat, and its postal code is 59755. The county has 4 incorporated towns, 10 census-designated places, and around two dozen smaller unincorporated communities and ranch settlements. Madison County is in the Mountain time zone.
Towns & Villages in Madison County
Thirty-four named places are listed below. Four are incorporated towns under Montana law (Ennis, Sheridan, Twin Bridges and the seat, Virginia City); ten are Census-Designated Places recognized by the Census Bureau but not self-governing; the rest are unincorporated communities, historic mining camps, and rural post-office points. Population figures are shown only where the 2020 census reports a figure for that specific place.
| Place | Type | Pop. | ZIP |
|---|---|---|---|
| Virginia City | Town · seat | — | 59755 |
| Ennis | Town | — | 59729 |
| Sheridan | Town | — | 59749 |
| Twin Bridges | Town | — | 59754 |
| Alder | CDP | — | 59710 |
| Big Sky | CDP | — | 59716 |
| Brandon | CDP | — | — |
| Harrison | CDP | — | 59735 |
| Jeffers | CDP | — | — |
| Mammoth | CDP | — | — |
| McAllister | CDP | — | 59740 |
| Norris | CDP | — | 59745 |
| Pony | CDP | — | 59747 |
| Silver Star | CDP | — | 59751 |
| Cameron | Unincorp. | — | 59720 |
| Nevada City | Unincorp. | — | — |
| Laurin | Unincorp. | — | — |
| Jefferson Island | Unincorp. | — | — |
| Rochester | Unincorp. | — | — |
| Ruby | Unincorp. | — | — |
| Beacon Point | Unincorp. | — | — |
| Beals | Unincorp. | — | — |
| Cliff Lake | Unincorp. | — | — |
| Cowboys Heaven | Unincorp. | — | — |
| Harrison Mill | Unincorp. | — | — |
| Junction | Unincorp. | — | — |
| Leiterville | Unincorp. | — | — |
| Red Bluff | Unincorp. | — | — |
| Shaws | Unincorp. | — | — |
| Sterling | Unincorp. | — | — |
| Summit | Unincorp. | — | — |
| Varney | Unincorp. | — | — |
| Waterloo | Unincorp. | — | — |
| Watkins | Unincorp. | — | — |
Big Sky is split between Madison, Gallatin and Park counties; only its western fringe, along the Gallatin River road, falls in Madison County, and the resort’s better-known base-area ZIP code (59716) is shared across the boundary. Nevada City sits a mile west of Virginia City and is best known today as a preserved open-air ghost-town museum rather than a residential place.
ZIP Codes
- 59755 — Virginia City (county seat)
- 59729 — Ennis
- 59749 — Sheridan
- 59754 — Twin Bridges
- 59735 — Harrison
- 59740 — McAllister
- 59710 — Alder
- 59720 — Cameron
- 59751 — Silver Star
- 59747 — Pony
- 59745 — Norris
Smaller communities such as Jeffers, Mammoth, Brandon, Laurin and the ranch settlements along the Ruby and Madison rivers use the ZIP code of their nearest post-office town rather than a code of their own.
Geography
Madison County spans the valleys of the Madison, Ruby and Jefferson rivers between the Tobacco Root Mountains, the Gravelly Range and the Madison Range, in the southwestern part of the state. The Madison River, one of three forks that form the Missouri, runs the length of the county and is a nationally known trout-fishing stream; Ennis Lake, formed by a hydroelectric dam near Ennis, sits on the river. The county borders Jefferson County to the north, Gallatin County to the east, Beaverhead County to the southwest, Silver Bow County to the northwest, and Fremont County, Idaho, across the state line to the south.
Demographics
Madison County had 8,623 residents at the 2020 census, spread across a land area of 3,587 square miles for a density of about 2.4 people per square mile — one of the more sparsely populated counties in Montana. Ennis is the largest community, followed by Sheridan. Household income figures specific to Madison County are not independently verified here; Montana’s statewide 2023 median household income was $70,804, and rural Madison County, with its large share of ranch and second-home property, tends to sit below that figure on a wage-income basis even where overall wealth is higher.
Economy & Local Life
Ranching and hay production anchor the local economy, particularly in the Ruby and Madison valleys, alongside a large seasonal tourism sector built on fly fishing, hunting, and the historic sites around Virginia City and Nevada City. The county’s western edge touches the Big Sky resort area, and county government, schools and small retail are concentrated in the four incorporated towns. Virginia City’s preserved 1860s townscape, run partly as a state-supported historic district, draws visitors through the summer season.
History
Madison County was created in 1865 by the Montana Territorial legislature and named for President James Madison. It was formed soon after the 1863 Alder Gulch gold strike, one of the richest placer gold discoveries in the American West, which drew thousands of miners to the boomtown of Virginia City almost overnight. Virginia City served as capital of Montana Territory from 1865 until 1875, when the capital moved to Helena. The same period produced the vigilante hangings of 1863–64, in which a citizens’ committee executed accused road agents around Virginia City and Nevada City — an episode still central to the area’s frontier history and museum interpretation today.
Getting There
US Highway 287 runs north–south through the county past Ennis and Virginia City, connecting to Montana Highway 41 at Twin Bridges and Montana Highway 84 near Norris.
- Bozeman — about 50 miles northeast
- Butte — about 60 miles northwest
- Dillon — about 55 miles southwest
- West Yellowstone — about 60 miles southeast
The nearest commercial airport is Bozeman Yellowstone International Airport in neighboring Gallatin County.
Frequently Asked Questions
Where is Madison County, Montana?
It is in the southwestern part of the state, bordering Idaho, along the Madison, Ruby and Jefferson river valleys.
What is the population of Madison County?
8,623 people, according to the 2020 census.
How big is Madison County?
3,603 square miles (9,330 km2), of which 3,587 square miles is land.
What is the county seat of Madison County?
Virginia City, the former territorial capital of Montana.
How many towns are in Madison County?
Four incorporated towns — Ennis, Sheridan, Twin Bridges and Virginia City — plus ten census-designated places and about twenty smaller unincorporated communities.
What ZIP codes are in Madison County?
Eleven, including 59755 (Virginia City), 59729 (Ennis), 59749 (Sheridan) and 59754 (Twin Bridges).
Why was Virginia City the territorial capital?
It was Montana’s largest town during the 1863 Alder Gulch gold rush, and the territorial legislature sat there from 1865 until the capital moved to Helena in 1875.
More counties in this state: Towns and villages in Montana.