Trains run once daily in each direction. The entire train ride takes about 9 hours total, with 1.5 hours between New York and Philadelphia, 2 hours between Philadelphia and Harrisburg, and 5.5 hours between Harrisburg and Pittsburgh. The Pennsylvanian runs a portion of the Three Rivers route, which ran from New York to Chicago. East of Harrisburg, the Pennsylvanian runs over Amtrak's own railroad, but between Harrisburg and Pittsburgh it runs over Norfolk Southern's ex-Pennsylvania Railroad line through Horseshoe Curve. The route east of Philadelphia is along the Northeast Corridor (originally owned by the PRR); the rest is the old main line of the PRR, consisting of the Amtrak-owned Keystone Corridor east of Harrisburg.
Services on the Pennsylvanian includes coach, business class (reserved deluxe seating), dinette (for food, snacks, and drinks), and Railfone for public telephone access, which is available in the food service cars.
Originally, this train was started to provide daytime departures between Philadelphia and Pittsburgh, and New York service was provided as a connecting train at Philadelphia. At the time the Pennsylvanian was inaugurated, the Broadway Limited was departing Pittsburgh at an inconvenient early morning hour. Since then, the length of the Pennsylvanian's route has undergone a number of iterations. The most recent iteration involved the cancellation of the Pennsylvanian as part of Amtrak's statuatory 180-day cancellation notice of service along a route. After that period, and after the required public hearings were conducted, the Pennsylvanian was restarted on March 8, 2005 as a truncation of the Three Rivers over the original route of the Pennsylvanian. Continuing service beyond Pittsburgh to Chicago, formerly provided by the Three Rivers, can be made by a transfer to the Capitol Limited at Pittsburgh.