Brownstone quarried in Portland was used in the construction of Hartford's Old State House in 1796. The vast majority of the brownstone buildings in Connecticut (see College Row at Wesleyan University and the Long Walk at Trinity College) as well as the famous brownstones in New York City were built with brownstone from Portland's quarries.
About half of the town's perimeter is made up of the Connecticut River. The town has eight marinas and boat clubs as well as three 18-hole golf courses.
As of the census of 2000, there were 8,732 people, 3,388 households, and 2,419 families residing in the town. The population density was 373.1 people per square mile (144.1/km²). There were 3,528 housing units at an average density of 150.7/sq mi (58.2/km²). The racial makeup of the town was 95.12% White, 2.44% Black or African American, 0.16% Native American, 0.52% Asian, 0.03% Pacific Islander, 0.46% from other races, and 1.27% from two or more races. Hispanic or Latino of any race were 1.96% of the population.
There were 3,388 households out of which 33.6% had children under the age of 18 living with them, 58.5% were married couples living together, 9.4% had a female householder with no husband present, and 28.6% were non-families. 24.1% of all households were made up of individuals and 10.4% had someone living alone who was 65 years of age or older. The average household size was 2.52 and the average family size was 3.01.
In the town the population was spread out with 25.5% under the age of 18, 4.5% from 18 to 24, 30.7% from 25 to 44, 24.7% from 45 to 64, and 14.6% 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 91.4 males.
The median income for a household in the town was $63,285, and the median income for a family was $73,036. Males had a median income of $48,849 versus $35,104 for females. The per capita income for the town was $28,229. About 3.0% of families and 5.1% of the population were below the poverty line, including 4.6% of those under age 18 and 8.9% of those age 65 or over.