Oakville is south of the city of St. Louis, and borders the Mississippi River; the area is generally referred to as South County or South St. Louis County.
Oakville is located at(38.458620, -90.319324).
According to the United States Census Bureau, the CDP has a total area of 18.1 mi². 16.1 mi² of it is land and 2.0 mi² of it (11.12%) is water.
As of the census of 2000, there were 35,309 people, 12,530 households, and 9,923 families residing in the CDP. The population density was 2,196.4/mi². There were 12,791 housing units at an average density of 795.7/mi². The racial makeup of the CDP was 97.89% White, 0.24% African American, 0.13% Native American, 0.92% Asian, 0.02% Pacific Islander, 0.20% from other races, and 0.60% from two or more races. Hispanic or Latino of any race were 1.03% of the population.
There were 12,530 households out of which 39.1% had children under the age of 18 living with them, 69.6% were married couples living together, 7.0% had a female householder with no husband present, and 20.8% were non-families. 17.3% of all households were made up of individuals and 5.8% had someone living alone who was 65 years of age or older. The average household size was 2.81 and the average family size was 3.20.
In the CDP the population was spread out with 27.0% under the age of 18, 8.9% from 18 to 24, 26.8% from 25 to 44, 27.6% from 45 to 64, and 9.6% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 97.2 males. For every 100 females age 18 and over, there were 94.0 males.
The median income for a household in the CDP was $68,248, and the median income for a family was $76,223. Males had a median income of $52,123 versus $33,604 for females. The per capita income for the CDP was $26,750. About 2.0% of families and 2.8% of the population were below the poverty line, including 3.3% of those under age 18 and 4.0% of those age 65 or over.
- Whammy host Todd Newton graduated from Oakville High School.
- Popular music talent Joe Devoto was born and raised in Oakville.
<googlemap lat="38.443762" lon="-90.318244" zoom="11" width="700" controls="large">38.443762, -90.318244, Oakville, MO, USA</googlemap>