Fairfield is a town in Teton County, Montana, United States.

[5] Even though the federal government opened Montana to homesteading in 1862, this area was not initially settled.

In 1902 irrigation projects began, which did lead to increased grain production.

[7] Today, Greenfield Irrigation District delivers water from Gibson Dam to approximately 83,000 acres surrounding this community.

"Greenfield Bench" and Fairfield now describe the hay and grain fields in the Sun River Valley.

Freezout Lake, an important bird migration site, is 5 miles to the west.

According to the United States Census Bureau, the town has a total area of 0.31 square miles (0.80 km2), all land.

The racial makeup of the town was 95.9% White, 1.3% Native American, and 2.8% from two or more races.

[19] From 2010 to 2015, the high school girls' basketball team, coached by Dustin Gordon, collected 120 consecutive wins solidifying one of the longest winning streaks for a high school girls' basketball team in the United States.

[22] Fairfield has a public library operated in a joint city-county arrangement.

[23] The Fairfield Sun Times is a weekly newspaper that has been in operation, under various names, since the town's founding.