Route 15, the Girard Avenue Line, is a trolley line operated by the Southeastern Pennsylvania Transportation Authority (SEPTA) along Girard Avenue through North and West Philadelphia, Pennsylvania, United States. As of 2007, it is the only surface trolley line in the City Transit Division that is not part of the Subway–Surface Trolley Lines. SEPTA PCC II vehicles are used on the line.

The Southeastern Pennsylvania Transportation Authority (SEPTA) is a regional public transportation authority that operates bus, rapid transit, commuter rail, light rail, and electric trolleybus services for nearly four million people in five counties in and around Philadelphia, Pennsylvania. It also manages projects that maintain, replace and expand its infrastructure, facilities and vehicles.