Jefferson County, Montana

Jefferson County is a county in Montana, United States. As of the 2020 census, the population was 12,085. Its county seat is Boulder. The county was created in 1865 and named for President Thomas Jefferson.
  • Country: United States
  • State: Montana
  • Founded: February 2, 1865
  • Named after: Thomas Jefferson
  • Seat: Boulder
  • Largest town: Clancy
  • Congressional district: 2nd

Nearby

Events

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4/20 Night

Fri, Apr 11

5:30 PM

(multiple times)

Lucky Stiff

Apr 11 · 7:30 PM

Grandstreet Theatre

(multiple times)

Tanner Laws @ The Westerner

Apr 11 · 8 PM

The Westerner

(multiple times)

Lakeside on Hauser | Tanner Laws Band

Apr 12 · 7 PM – 4 AM

Lakeside on Hauser Lake

(multiple times)

Cars & Coffee

Apr 13 · 8 – 10 AM

220 S Broadway St

(multiple times)

Tap Room Trivia

Apr 16 · 7:30 – 9 PM

Lewis & Clark Brewing Company

(multiple times)

Clint Reimann @ Broadwater Hot S…

Apr 19 · 6 PM

Broadwater Hot Springs

(multiple times)

USA – 6 Days Yellowstone Wint…

Wed, Apr 16

2:00 AM

(multiple times)

Mom and Me Tea

Sun, Apr 27

10:00 AM

(multiple times)

Winnie Brave | Pony, MT

May 24 · 7 PM – 5 AM

Pony Bar

(multiple times)

Winnie Brave | Willow Creek, MT

May 25 · 6 PM – 4 AM

Woolzie's Willow Creek Cafe & Supper Club

(multiple times)

Junie B. Jones Jr.

May 30 · 7:30 PM

Grandstreet Theatre

(multiple times)

Little Jane at Gallatin River Lod…

Jun 11 · 5:30 PM – 2 AM

Gallatin River Lodge

(multiple times)

Summer Camps – Gamer Craft

Mon, Jun 16

1:00 PM

(multiple times)

Last Chance Stampede

Wed, Jul 23

Clark County Fairgrounds

(multiple times)

Headwaters Country Jam 202…

Jul 24 · 12 – 11:59 PM

Headwaters Country Jam

(multiple times)

Headwaters Country Jam 2025

Jul 24 – 27

Headwaters Country Jam

(multiple times)

Bayker Blankenship @ The Bridge at …

Jul 24 · 7 PM

The Bridge at Three Forks

(multiple times)

dave matthews

Aug 1 · 5:30 PM – 3:30 AM

Big Sky Events Arena

(multiple times)

MASTERWORKS CONCERT VI: Th…

May 9, 2026

Helena Civic Center

(multiple times)

Data from: en.wikipedia.org