Kōloa is an unincorporated community and census-designated place (CDP) in Kauaʻi County, Hawaiʻi, United States. The population was 2,144 at the 2010 census, up from 1,942 at the 2000 census. The first successful sugarcane plantation in the Hawaiian Islands was started here in 1835. It became a part of Grove Farm in 1948.
Kōloa is located on the southern side of the island of Kauai at 21°54′26″N 159°27′57″W / 21.90722°N 159.46583°W / 21.90722; -159.46583 (21.907137, -159.465877). It is bordered to the northwest by Omao and to the south by Poipu.
According to the United States Census Bureau, the CDP has a total area of 1.2 square miles (3.2 km), all of it recorded as land. Waikomo Stream passes through the center of the community.
As of the census of 2000, there were 1,942 people, 693 households, and 507 families residing in the CDP. The population density was 1,629.5 people per square mile (630.1/km). There were 748 housing units at an average density of 627.6 per square mile (242.7/km). The racial makeup of the CDP was 20.2% White, 0.4% African American, 0.3% Native American, 43.8% Asian, 7.8% Pacific Islander, 1.2% from other races, and 26.4% from two or more races. Hispanic or Latino of any race were 11.4% of the population.
There were 693 households out of which 34.8% had children under the age of 18 living with them, 47.2% were married couples living together, 18.9% had a female householder with no husband present, and 26.8% were non-families. 22.5% of all households were made up of individuals and 8.7% had someone living alone who was 65 years of age or older. The average household size was 2.80 and the average family size was 3.25.
In the CDP the population was spread out with 26.0% under the age of 18, 9.9% from 18 to 24, 26.7% from 25 to 44, 21.6% from 45 to 64, and 15.8% who were 65 years of age or older. The median age was 36 years. For every 100 females, there were 101.0 males. For every 100 females age 18 and over, there were 96.3 males.
The median income for a household in the CDP was $34,786, and the median income for a family was $43,393. Males had a median income of $31,125 versus $25,938 for females. The per capita income for the CDP was $16,224. About 16.7% of families and 17.8% of the population were below the poverty line, including 26.5% of those under age 18 and 6.0% of those age 65 or over.