On February 26, 2012, the Blues traded Bishop to the Ottawa Senators in exchange for a second-round draft pick in the 2013 NHL Entry Draft. On March 6, 2012, Bishop made his Senators debut in a 7–3 win over the Tampa Bay Lightning. During the 2012–13 NHL lockout, Bishop played for the Senators AHL-affiliate, the Binghamton Senators. He was called back up to serve as Craig Anderson's backup after the lockout was over.