Irwin is an unincorporated community and census-designated place (CDP) in Lancaster County, South Carolina, United States.

[7] It is bordered to the east by Springdale, and Lancaster, the county seat, is 4 miles (6 km) to the northeast.

The Irwin CDP includes the neighborhood of Gooch Crossroad.

[8] Via Cane Creek, Irwin is part of the Catawba River watershed.

20.5% of all households were made up of individuals, and 9.8% had someone living alone who was 65 years of age or older.