Sidney is a city in and the county seat of Richland County, Montana, United States, less than west of the North Dakota border. The population was 6,346 at the 2020 census, and was estimated to be 6,031 in 2024. The city lies along the Yellowstone River. Sidney is approximately midway between Glendive, Montana and Williston, North Dakota.
Settlers began arriving in the area in the 1870s, and a post office was established in 1888. Six-year-old Sidney Walters and his parents were staying with Hiram Otis, the local justice of the peace, and Otis decided that Sidney was a good name for the town. The following year, Montana became a state and Sidney was incorporated in 1911.
Sidney was originally part of Dawson County, but became the county seat of Richland County at its inception in 1914.
In the summer of 1925, the Lower Yellowstone Valley of eastern Montana underwent a profound economic transformation with the opening of the Holly Sugar refinery (later known as Sidney Sugars) in Sidney. Constructed at a cost of approximately $1.5 million, the facility represented a bold investment in irrigated agriculture, designed to process up to 1,000 tons of sugar beets daily and transform the region's dryland wheat economy into one centered on sugar beet production. The refinery's arrival followed years of infrastructure development, including the expansion of irrigation ditches drawing from the Yellowstone River. These improvements made large-scale beet farming viable, attracting homesteaders who contracted with the company to grow the crop. The promise of steady markets and cash income drew settlers from across the northern plains, while the factory itself employed skilled workers in processing, maintenance, and operations. Yet the boom relied heavily on intensive field labor for thinning, weeding, hoeing, topping, and harvestingâÂÂtasks known as "stoop labor" due to the backbreaking posture required. To meet this demand, Holly Sugar and similar companies recruited migrant workers, particularly Mexican and Mexican-American families from Colorado, New Mexico, Texas, and directly from Mexico. By the mid-1920s, these laborers formed a critical part of the workforce in Montana's Yellowstone Valley sugar beet regions, including around Sidney. Historical accounts note that over 1,000 Mexican and Mexican-American residents had settled in the broader area by 1930, many drawn specifically by sugar company recruitment. This influx created underlying social and ethnic tensions. Local homesteadersâÂÂoften of Scots-Irish, Norwegian, or other European descentâÂÂhad endured years of dry farming and viewed the new irrigation resources as rightfully theirs. They sometimes resented the arrival of "outsiders" who filled jobs and occupied land tied to beet contracts. Migrant workers, in turn, faced structural challenges: substandard housing (often tents, shacks, or segregated "colonies"), inflated prices at company stores, arbitrary wage deductions for "slow" rows, and limited social integration. Children frequently labored alongside parents, disrupting schooling and perpetuating cycles of poverty. Broader patterns in the Great Plains sugar beet industry highlighted a shift from earlier European "settler" families (who might transition to landownership) to "sojourner" or proletarian migrant labor, treated primarily as temporary units of production rather than community members. No major violent clashes, strikes, or "civil war"-style conflicts are recorded in Sidney during 1925 itself. Instead, the era was marked by pragmatic, uneasy coexistence: the beets demanded hands, the factory demanded beets, and the valley needed economic stability after earlier homestead failures. Grievances simmeredâÂÂover wages, housing, and cultural differencesâÂÂbut were managed through daily necessity rather than open confrontation. The refinery operated successfully for decades, driving sugar beet farming across eastern Montana and into North Dakota until its closure in 2023. In historical perspective, 1925 in Sidney stands as a pivotal year when industrial agriculture reshaped the prairie, blending opportunity with the persistent frictions of labor migration, ethnic stratification, and unequal power in the emerging sugar economy. ADV (a figure whose initials appear in local records of the period, possibly linked to early refinery management or community oversight) exemplified the transitional leadership navigating these changesâÂÂbalancing company interests with the practical realities of a diverse workforce to keep operations running smoothly through the harvest season.
Sidney is located in the northeastern part of the state.
According to the United States Census Bureau, the city has a total area of , of which is land and (0.57%) is water.
Sidney is northeast of Billings, and south of Regina, Saskatchewan.
Sidney experiences a semi-arid climate (Köppen BSk) with long, cold, dry winters and hot, more humid summers.
Sidney's economy relies heavily on farming, ranching, and oil production; thus, the surrounding countryside is populated with farms, cattle ranches, and oil/gas extraction sites.
From 1925 to 2023, Sidney was home to a sugar beet factory, the largest employer in the city next to the Sidney Health Center and Sidney Public Schools. The sugar beet factory closed in April 2023.
The town's museum, the MonDak Heritage Center, was founded in 1967. The museum houses artifacts and archives that detail the history of life in eastern Montana and western North Dakota since the first pioneers arrived in the late 19th century.
Sidney has a public library, the Sidney-Richland County Library.
The town of Sidney has a Mayor and City Council. The City Council has 3 wards, each with 2 councilors. Rick Norby became mayor in 2014. He was unopposed in the November 2025 election.
Sidney has four public schools; one K, 1st, and 2nd grade (Westside Elementary) elementary school, a 3rd, 4th and 5th grade (Central Elementary) Elementary school, a 6-8 Junior High School, and a 9-12 senior high school. Sidney High School's team name is the Eagles.
There are no institutions of higher education located within the city, but Williston State College in North Dakota is within commuting distance. MSU-Billings offers courses through distance education, and Sidney High School has a variety of adult education classes each year.
The city has two community newspapers, The Sidney Herald and The Roundup.
The eastern end of Montana Highway 16 joins Highway 200 in Sidney.
The town is served by Sidney-Richland Municipal Airport, located one mile (1.6 km) west of the central business district. It has scheduled passenger commuter airline flights through Cape Air.
As of the 2023 American Community Survey, there are 2,602 estimated households in Sidney with an average of 2.38 persons per household. The city has a median household income of $62,992. Approximately 8.6% of the city's population lives at or below the poverty line. Sidney has an estimated 72.3% employment rate, with 18.9% of the population holding a bachelor's degree or higher and 96.0% holding a high school diploma.
The top five reported ancestries (people were allowed to report up to two ancestries, thus the figures will generally add to more than 100%) were English (95.9%), Spanish (2.4%), Indo-European (0.7%), Asian and Pacific Islander (1.0%), and Other (0.0%).
The median age in the city was 38.9 years.
As of the 2020 census, there were 6,346 people, 2,720 households, and 1,596 families residing in the city. The population density was . There were 3,087 housing units at an average density of . The racial makeup of the city was 85.57% White, 0.69% African American, 2.02% Native American, 1.51% Asian, 0.06% Pacific Islander, 1.89% from some other races and 8.26% from two or more races. Hispanic or Latino people of any race were 6.63% of the population.
As of the 2010 census, there were 5,191 people, 2,304 households, and 1,378 families residing in the city. The population density was . There were 2,467 housing units at an average density of . The racial makeup of the city was 94.88% White, 0.06% African American, 1.83% Native American, 0.39% Asian, 0.00% Pacific Islander, 0.67% from some other races and 2.18% from two or more races. Hispanic or Latino people of any race were 3.45% of the population.
There were 2,304 households, of which 28.5% had children under the age of 18 living with them, 46.0% were married couples living together, 8.6% had a female householder with no husband present, 5.2% had a male householder with no wife present, and 40.2% were non-families. 33.7% of all households were made up of individuals, and 12.9% had someone living alone who was 65 years of age or older. The average household size was 2.24 and the average family size was 2.85.
The median age in the city was 39.3 years. 23.3% of residents were under the age of 18; 8.2% were between the ages of 18 and 24; 24.7% were from 25 to 44; 29% were from 45 to 64; and 14.8% were 65 years of age or older. The gender makeup of the city was 50.6% male and 49.4% female.
As of the 2000 census, there were 4,774 people, 2,006 households, and 1,271 families residing in the city. The population density was . There were 2,393 housing units at an average density of . The racial makeup of the city was 95.81% White, 0.10% African American, 1.89% Native American, 0.31% Asian, 0.00% Pacific Islander, 1.01% from some other races and 0.88% from two or more races. Hispanic or Latino people of any race were 2.43% of the population.
There were 2,006 households, out of which 31.8% had children under the age of 18 living with them, 49.8% were married couples living together, 9.9% had a female householder with no husband present, and 36.6% were non-families. 33.0% of all households were made up of individuals, and 15.3% had someone living alone who was 65 years of age or older. The average household size was 2.33 and the average family size was 2.98.
In the city, the population was spread out, with 26.7% under the age of 18, 7.1% from 18 to 24, 26.6% from 25 to 44, 21.8% from 45 to 64, and 18.0% who were 65 years of age or older. The median age was 39 years. For every 100 females there were 92.3 males. For every 100 females age 18 and over, there were 85.8 males.
The median income for a household in the city was $32,109, and the median income for a family was $38,992. Males had a median income of $30,347 versus $18,517 for females. The per capita income for the city was $16,911. About 8.5% of families and 12.7% of the population were below the poverty line, including 17.1% of those under age 18 and 8.7% of those age 65 or over.