39.86666667, -76.12638889
Colerain Township is a township in southeastern Lancaster County, Pennsylvania, United States. The population was 3,883 at the 2020 census, an increase over the figure of 3,635 tabulated in 2010. It is part of the Solanco School District.
Colerain Township was organized as a township in 1738. It was settled mainly by the Irish and was named after Coleraine, a seaport town in County Londonderry, now in Northern Ireland. Records show that Presbyterian Scots and Scotch-Irish also moved into Colerain Township very early into its settlement.
According to the 2020 "ACS 5-Year Estimates Data Profiles", 61.8% of the township's population spoke only English, while 38.1 spoke an "other [than Spanish] Indo-European language" (basically Pennsylvania German/German).