Big Beaver is a borough in Beaver County, Pennsylvania, United States. The population was 1,970 at the 2010 census.According to the United States Census Bureau, the borough has a total area of 18.0 square miles (47 km2), of which, 17.8 square miles (46 km2) of it is land and 0.2 square miles (0.52 km2) of it (1.00%) is water.
As of the census of 2000, there were 2,186 people, 869 households, and 635 families residing in the borough. The population density was 122.7 people per square mile (47.4/km²). There were 905 housing units at an average density of 50.8 per square mile (19.6/km²). The racial makeup of the borough was 98.17% White, 0.69% African American, 0.23% Native American, 0.18% Asian, 0.18% from other races, and 0.55% from two or more races. Hispanic or Latino of any race were 0.78% of the population.
There were 869 households out of which 26.5% had children under the age of 18 living with them, 63.2% were married couples living together, 7.1% had a female householder with no husband present, and 26.9% were non-families. 23.2% of all households were made up of individuals and 10.7% had someone living alone who was 65 years of age or older. The average household size was 2.47 and the average family size was 2.90.
In the borough the population was spread out with 20.1% under the age of 18, 5.5% from 18 to 24, 26.8% from 25 to 44, 29.5% from 45 to 64, and 18.1% who were 65 years of age or older. The median age was 44 years. For every 100 females there were 95.2 males. For every 100 females age 18 and over, there were 96.3 males.
The median income for a household in the borough was $37,297, and the median income for a family was $43,523. Males had a median income of $34,688 versus $23,945 for females. The per capita income for the borough was $17,228. About 7.0% of families and 9.8% of the population were below the poverty line, including 16.2% of those under age 18 and 4.5% of those age 65 or over.