Judith Basin County is a county in the U.S. state of Montana. As of the 2020 census, the population was 2,023. Its county seat is the town of Stanford.

Judith Basin County was formed of area taken from western Fergus and eastern Cascade counties on December 10, 1920. In 1895, Yogo sapphires were discovered at Yogo Gulch, about 15 miles southwest of Utica, which at the time was in Fergus County.

According to the United States Census Bureau, the county has a total area of 1,871 square miles (4,850 km), of which 1,870 square miles (4,800 km) is land and 0.8 square miles (2.1 km) (0.04%) is water.

• Lewis and Clark National Forest (part)

• Hobson

• Stanford (county seat)

• Utica

• Ubet

This small county strongly leans Republican; a Democrat has not won this county in a Presidential race since Lyndon Johnson's landslide win in 1964.

United States presidential election results for Judith Basin County, Montana

Year	Republican		Democratic		Third party(ies)
	No.	%	No.	%	No.	%
2020	1,040	77.38%	275	20.46%	29	2.16%
2016	872	72.19%	235	19.45%	101	8.36%
2012	854	70.29%	337	27.74%	24	1.98%
2008	801	64.81%	397	32.12%	38	3.07%
2004	944	73.41%	322	25.04%	20	1.56%
2000	1,057	75.82%	278	19.94%	59	4.23%
1996	753	56.28%	452	33.78%	133	9.94%
1992	610	42.16%	409	28.27%	428	29.58%
1988	902	59.50%	590	38.92%	24	1.58%
1984	1,050	67.74%	483	31.16%	17	1.10%
1980	1,030	63.31%	480	29.50%	117	7.19%
1976	809	50.12%	772	47.83%	33	2.04%
1972	961	59.54%	557	34.51%	96	5.95%
1968	804	53.03%	606	39.97%	106	6.99%
1964	678	45.14%	822	54.73%	2	0.13%
1960	721	46.10%	842	53.84%	1	0.06%
1956	789	48.20%	848	51.80%	0	0.00%
1952	1,074	57.96%	746	40.26%	33	1.78%
1948	609	36.64%	934	56.20%	119	7.16%
1944	691	39.55%	1,049	60.05%	7	0.40%
1940	670	35.02%	1,215	63.51%	28	1.46%
1936	645	28.91%	1,534	68.76%	52	2.33%
1932	720	33.79%	1,280	60.07%	131	6.15%
1928	1,342	56.77%	978	41.37%	44	1.86%
1924	888	41.34%	480	22.35%	780	36.31%

Historical population

Census	Pop.	Note	%±
1930	5,238		—
1940	3,655		−30.2%
1950	3,200		−12.4%
1960	3,085		−3.6%
1970	2,667		−13.5%
1980	2,646		−0.8%
1990	2,282		−13.8%
2000	2,329		2.1%
2010	2,072		−11.0%
2020	2,023		−2.4%
2022 (est.)	2,105		4.1%
U.S. Decennial Census 1790–1960, 1900–1990, 1990–2000, 2010–2020

As of the 2020 census, there were 2,023 people living in the county.

As of the 2010 census, there were 2,072 people, 924 households, and 600 families in the county. The population density was 1.1 inhabitants per square mile (0.42/km). There were 1,336 housing units at an average density of 0.7 per square mile (0.27/km). The racial makeup of the county was 98.3% white, 0.8% American Indian, 0.1% Asian, 0.1% from other races, and 0.7% from two or more races. Those of Hispanic or Latino origin made up 1.2% of the population. In terms of ancestry, 30.9% were German, 16.7% were English, 16.1% were Irish, 10.3% were Norwegian, 6.7% were Czech, 5.0% were Danish, and 1.7% were American.

Of the 924 households, 24.0% had children under the age of 18 living with them, 55.7% were married couples living together, 5.2% had a female householder with no husband present, 35.1% were non-families, and 30.3% of all households were made up of individuals. The average household size was 2.24 and the average family size was 2.80. The median age was 48.3 years.

The median income for a household in the county was $41,473 and the median income for a family was $54,479. Males had a median income of $36,295 versus $29,750 for females. The per capita income for the county was $24,029. About 6.4% of families and 9.9% of the population were below the poverty line, including 8.9% of those under age 18 and 9.0% of those age 65 or over.

• List of lakes in Judith Basin County, Montana
• List of mountains in Judith Basin County, Montana
• National Register of Historic Places listings in Judith Basin County, Montana

• Official website

47°02′N 110°16′W / 47.04°N 110.26°W / 47.04; -110.26