The deal is for a combined $6 million, averaging to $3 million a year, a source told ESPN.com's Pierre LeBrun.
Regehr was acquired by the Kings from the Buffalo Sabres on April 1 in exchange for a second-round pick in the 2014 and 2015 drafts. Regehr appeared in 41 regular-season games this season with the Kings and Buffalo, posting four points (all assists) and 23 penalty minutes.
The 6-foot-3, 225-pound native of Recife, Brazil, has appeared in all 13 playoff games with the Kings this postseason and has one assist and four penalty minutes.
With the absence of key defensemen Willie Mitchell, who has missed the entire season, and Matt Greene, who played only five games during the season and recently returned to the lineup, the addition of Regehr has helped stabilize the Kings' defense with a veteran presence and given them a chance to repeat as Cup champions heading into Game 1 of the Western Conference finals against the Chicago Blackhawks on Saturday.
"They told me they wanted me to be a good defenseman and a physical guy," Regehr said Thursday. "Help around the penalty kill and do things like that. I had a really good understanding of the things that I needed to work on and (Kings coach) Darryl (Sutter) had mentioned they were missing a veteran presence during the season unfortunately because of the injuries to Matt Greene and Willie Mitchell. I just tried to come in and help."
Regehr's return solidifies the Kings' blue line during a potentially busy summer. Veteran defenseman Rob Scuderi is an unrestricted free agent, while defensemen Slava Voynov, Jake Muzzin, Alec Martinez and Keaton Ellerby are restricted free agents.
In 943 career regular-season games with the Calgary Flames, Sabres and Kings, Regehr has 172 points and 881 penalty minutes. He also has appeared in 54 playoff games, recording 16 points and 32 penalty minutes. He originally was selected by Colorado in the first round of the 1998 draft.
Information from The Associated Press was used in this report.