Otranto is an unincorporated community and census-designated place in Otranto Township, Mitchell County, in the U.S. state of Iowa. As of the 2020 census the population was 27, unchanged from 2010.

The community is in northwestern Mitchell County, 7 miles (11 km) northwest of St. Ansgar, the post office serving Otranto, and 18 miles (29 km) northwest of Osage, the county seat. The Minnesota border is 3 miles (5 km) to the north.

Otranto is located along the Cedar River, approximately 4 miles (6 km) southwest of Mona.

Historical population

Census	Pop.	Note	%±
2010	27		—
2020	27		0.0%
U.S. Decennial Census

As of the census of 2020, there were 27 people, 14 households, and 13 families residing in the community. The population density was 65.9 inhabitants per square mile (25.4/km). There were 14 housing units at an average density of 34.1 per square mile (13.2/km). The racial makeup of the community was 81.5% White, 0.0% Black or African American, 3.7% Native American, 0.0% Asian, 0.0% Pacific Islander, 7.4% from other races and 7.4% from two or more races. Hispanic or Latino persons of any race comprised 11.1% of the population.

Of the 14 households, 21.4% of which had children under the age of 18 living with them, 92.9% were married couples living together, 0.0% were cohabitating couples, 0.0% had a female householder with no spouse or partner present and 7.1% had a male householder with no spouse or partner present. 7.1% of all households were non-families. 7.1% of all households were made up of individuals, 7.1% had someone living alone who was 65 years old or older.

The median age in the community was 54.8 years. 22.2% of the residents were under the age of 20; 0.0% were between the ages of 20 and 24; 7.4% were from 25 and 44; 48.1% were from 45 and 64; and 22.2% were 65 years of age or older. The gender makeup of the community was 51.9% male and 48.1% female.