Ennis is a town in Madison County, Montana, United States, in the southwestern part of the state. The population was 838 at the 2010 census. The town is flanked by Tobacco Root Mountains to the northwest, the Gravelly Range to the southwest and the Madison Range to the east.  Approximately 19km north of town, the Madison Dam creates Ennis Lake at the head of Bear Trap Canyon.

The town of Ennis was incorporated in 1956. Today, Ennis is a community of 1,000 plus people. The valley is primarily cattle country producing prize Herefords and Black Angus along with rotating crops of hay and grain. Timber is harvested from nearby national forests and gold mining is making a comeback. As a resort community, the Town of Ennis attracts an influx of seasonal population because of its location in the heart of prime fishing and hunting territory.

A vibrant community of approximately 900 residents, Ennis features year-round outdoor recreation and an authentic, western atmosphere.

Ennis is the center of a long-standing ranching economy in the Madison River valley. Large cattle and sheep ranches dot the valley north and south of the town along the river. Ennis is also a major tourist attraction and angling destination for fly fisherman targeting the rainbow and brown trout that the Madison River is famous for. The small town hosts at least three fly shops and numerous resorts that cater to fly anglers with guided fishing trips on the Madison and in nearby Yellowstone National Park. Ennis is home to Willie’s Distillery, known for its bourbon and moonshine, and one of the growing number of micro-distilleries in Montana.