As of the census of 2000, there were 182,023 people, 66,443 households, and 47,440 families residing in the county. The population density was 294 people per square mile (114/km²). There were 70,616 housing units at an average density of 114 per square mile (44/km²). The racial makeup of the county was 85.73% White, 9.51% Black or African American, 0.29% Native American, 1.90% Asian, 0.04% Pacific Islander, 1.32% from other races, and 1.20% from two or more races. 2.78% of the population were Hispanic or Latino of any race.
By 2005 there had been small but noticeable shifts. The Latino population had climed to 4.8%, which meant that in light of the growing county population the number of Latinos in the county had nearly doubled, now numbering about 10,000. The African American population had climed to 11.3% of the population. The Asian population had climbed to 2.6% of the population.
In 2000 there were 66,443 households out of which 37.80% had children under the age of 18 living with them, 56.30% were married couples living together, 11.20% had a female householder with no husband present, and 28.60% were non-families. 20.80% of all households were made up of individuals and 5.10% had someone living alone who was 65 years of age or older. The average household size was 2.65 and the average family size was 3.09.
In the county, the population was spread out with 26.40% under the age of 18, 13.20% from 18 to 24, 33.50% from 25 to 44, 19.40% from 45 to 64, and 7.50% who were 65 years of age or older. The median age was 31 years. For every 100 females there were 99.10 males. For every 100 females age 18 and over, there were 97.20 males.
The median income for a household in the county was $46,312, and the median income for a family was $53,553. Males had a median income of $36,788 versus $26,555 for females. The per capita income for the county was $19,938. About 5.80% of families and 9.00% of the population were below the poverty line, including 8.50% of those under age 18 and 9.40% of those age 65 or over.
U.S. Census 2006 estimates put the population of Rutherford County at 228,829. This represented over 25% population growth since the 2000 census.