Valrico began as a region of cotton plantations known as Long Pond. The arrival of the Florida Central and Peninsular Railroad in 1890 brought many new immigrants from points north. William G. Tousey, a philosophy professor from Tufts College, gave the community its current name, Spanish for "valley of gold".
As of the censusGR2 of 2000, there were 6,582 people, 2,632 households, and 1,826 families residing in the community. The population density was 454.6/km² (1,176.9/mi²). There were 2,831 housing units at an average density of 195.5/km² (506.2/mi²).
There were 2,632 households out of which 29.4% had children under the age of 18 living with them, 57.0% were married couples living together, 8.4% had a female householder with no husband present, and 30.6% were non-families. 25.8% of all households were made up of individuals and 14.4% had someone living alone who was 65 years of age or older. The average household size was 2.49 and the average family size was 2.99.
In the community the population was spread out with 24.2% under the age of 18, 6.5% from 18 to 24, 29.1% from 25 to 44, 22.5% from 45 to 64, and 17.7% who were 65 years of age or older. The median age was 39 years. For every 100 females there were 95.0 males. For every 100 females age 18 and over, there were 93.1 males.
The median income for a household in the community was $39,155, and the median income for a family was $50,475. Males had a median income of $32,917 versus $24,746 for females. The per capita income for the community was $20,432. About 3.8% of families and 7.5% of the population were below the poverty line, including 7.3% of those under age 18 and 8.4% of those age 65 or over.