Deltona was laid out originally as a retirement community in 1963. Due to its proximity to downtown Orlando and its theme parks via I-4, the area grew very rapidly between 1970 and 2000 and Deltona has served as a bedroom community for commuters to Orlando ever since. It grew so fast that residents decided to incorporate it into an official city on 31 December 1995.
As of the censusGR2 of 2000, there were 69,543 people, 24,896 households, and 19,518 families residing in the city. The population density was 750.4/km² (1,943.7/mi²). There were 26,417 housing units at an average density of 285.1/km² (738.4/mi²).
There were 24,896 households out of which 37.0% had children under the age of 18 living with them, 61.5% were married couples living together, 12.4% had a female householder with no husband present, and 21.6% were non-families. 16.5% of all households were made up of individuals and 7.8% had someone living alone who was 65 years of age or older. The average household size was 2.79 and the average family size was 3.10.
In the city the population was spread out with 27.0% under the age of 18, 7.5% from 18 to 24, 29.1% from 25 to 44, 21.4% from 45 to 64, and 15.0% who were 65 years of age or older. The median age was 37 years. For every 100 females there were 94.3 males. For every 100 females age 18 and over, there were 91.0 males.
The median income for a household in the city was $39,736, and the median income for a family was $42,122. Males had a median income of $31,087 versus $23,482 for females. The per capita income for the city was $16,648. About 6.2% of families and 8.1% of the population were below the poverty line, including 10.6% of those under age 18 and 6.0% of those age 65 or over.