Loco is a town in Stephens County, Oklahoma, United States. The population was 150 at the 2000 census.

Two theories exist as to how Loco acquired its name. One theory, popularized by the Oklahoma Department of Transportation, states that the community was named for locoweed found in the area. The second theory, proposed by the niece of founder Albert G. Cranfill, suggests the name came from the Latin locus. It has frequently been noted on lists of unusual place names.

According to the United States Census Bureau, the village has a total area of 0.3 square miles (0.78 km), all land.

Historical population

Census	Pop.	Note	%±
1930	333		—
1940	268		−19.5%
1950	236		−11.9%
1960	268		13.6%
1970	193		−28.0%
1980	215		11.4%
1990	160		−25.6%
2000	150		−6.2%
2010	122		−18.7%
2020	99		−18.9%
U.S. Decennial Census

As of the census of 2000, there were 150 people, 67 households, and 44 families residing in the town. The population density was 571.5 inhabitants per square mile (220.7/km). There were 82 housing units at an average density of 312.4 per square mile (120.6/km). The racial makeup of the town was 87.33% White, 8.00% Native American, and 4.67% from two or more races.

There were 67 households, out of which 22.4% had children under the age of 18 living with them, 50.7% were married couples living together, 9.0% had a female householder with no husband present, and 34.3% were non-families. 28.4% of all households were made up of individuals, and 17.9% 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 2.68.

The village's population was spread out, with 19.3% under the age of 18, 6.0% from 18 to 24, 24.7% from 25 to 44, 32.0% from 45 to 64, and 18.0% who were 65 years of age or older. The median age was 45 years. For every 100 females, there were 100.0 males. For every 100 females age 18 and over, there were 98.4 males.

The median income for a household in Loco was $19,375, and the median income for a family was $30,000. Males had a median income of $30,000 versus $20,357 for females. The per capita income for the town was $11,440. There were 10.0% of families and 16.8% of the population living below the poverty line, including 19.4% of under eighteens and 41.7% of those over 64.

• Robert McMurtry (1950–2012), author, painter