For geographic and demographic information on specific parts of the town of Falmouth, please see the articles on East Falmouth, Falmouth (CDP), North Falmouth, Teaticket, West Falmouth, and Woods Hole.

There are 13,859 households out of which 24.2% have children under the age of 18 living with them, 52.0% are married couples living together, 10.1% have a woman whose husband does not live with her, and 35.2% are non-families. 29.8% of all households are made up of individuals and 14.0% have someone living alone who is 65 years of age or older. The average household size is 2.30 and the average family size is 2.84.

In the town the population is spread out with 20.7% under the age of 18, 4.8% from 18 to 24, 24.5% from 25 to 44, 27.5% from 45 to 64, and 22.5% who are 65 years of age or older. The median age is 45 years. For every 100 females there are 87.6 males. For every 100 females age 18 and over, there are 83.9 males.

The median income for a household in the town is $48,191, and the median income for a family is $57,422. Males have a median income of $41,797 versus $28,867 for females. The per capita income for the town is $27,548. 6.9% of the population and 4.5% of families are below the poverty line. Out of the total people living in poverty, 8.8% are under the age of 18 and 6.2% are 65 or older.