Most of PA 655 was once Pennsylvania Route 76. From 1928 to Spring 1964, PA 76 occupied what is now PA 655 from the Maryland state line to Pennsylvania Route 829 in Cass Township, as well as PA 829 from Cass Township to Mill Creek and PA 655 from Mill Creek to Reedsville. The section of present PA 655 between Saltillo and Mill Creek was designated part of PA 376. In spring 1964, PA 655 was assigned to its current alignment, replacing the PA 76 and PA 376 designations. This change was made to remove numbering conflicts that resulted from the designation of I-76 and I-376 in Pennsylvania. Pennsylvania Route 655 Truck is a truck route of PA 655 that bypasses a weight-restricted bridge over Saddlers Run on which trucks over 36 tons and combination loads over 40 tons are prohibited. It was signed in 2013.