It begins at U.S. Route 12 (US 12) at Avon and ends at MT 200 north of Helmville.

MT 141 begins in Avon at an intersection with US 12.

The highway heads to the northwest through the plains between the Garnet Range to the west and the Helena National Forest to the east.

The highway ends at an intersection with MT 200 about six miles (9.7 km) north of Helmville.

[2] The entire route is in Powell County.