The win gave the Flyers a .500 record for the first time this season, at 11-11-1. Philadelphia has won five of its last seven games.
Marc Methot scored for the Senators, who lost in regulation for the first time since Feb. 16.
Goalie Ben Bishop had won his last four starts for Ottawa, posting 1.69 goals-against average during the stretch. But the Senators have had trouble scoring on the road and struggled to get quality chances against the Flyers.