According to the United States Census Bureau, the CDP has a total area of 0.58 square miles (1.5 km2), all land. Harleigh is located less than one mile north of the city of Hazleton, along PA 940 (an east-west road). The western terminus of PA 940 is located just west of Harleigh at PA 309 (a north-south highway); it connects Hazleton (to the south) with Mountain Top and Wilkes-Barre (to the north).