In his first season with Buffalo, 2011–12, Regehr led the Sabres with 172 hits and finished second with 112 blocked shots. His one-goal on the season ended another lengthy scoring drought that lasted nearly 11 months. His tenure with the Sabres ended 21 games into the 2012–13 season. In the final year of his contract and with Buffalo out of playoff contention, he was dealt to the Los Angeles Kings on April 1, 2013, in exchange for two second round draft picks. The Kings acquired Regehr to add a veteran presence and aid the team's penalty kill. He appeared in 41 games during the season, split between the two teams, and recorded four assists. Shortly after the Kings reached the third round of the 2013 Stanley Cup Playoffs, Regehr and the team agreed to a two-year, $6 million contract extension. After the Kings were eliminated from the post-season by the Chicago Blackhawks, Kings' coach Darryl Sutter revealed he had played the entire playoffs with an elbow injury that required off-season surgery to repair.