The 23-year-old defenseman could have been a restricted free agent after this season. He has NHL career highs of 11 assists, 13 points, a plus-10 rating, 60 shots on goal, 69 blocked shots and average time on ice per game (21:49) in 55 games, two from his NHL career high set last season.
"We're excited to have a player of Mikey Anderson's caliber signed to the Kings long term," Kings general manager Rob Blake said. "Mikey has not only developed into a trusted, shut-down player on the ice, but a well-respected individual in the room that we envision continuing to grow into our leadership core."
Anderson, chosen by the Kings in the fourth round (No. 103) of the 2017 NHL Draft, has 33 points (six goals, 27 assists) in 172 regular-season games. He made his Stanley Cup Playoff debut last season and had one assist while averaging 19:49 of ice time during a seven-game loss to the Edmonton Oilers in the Western Conference First Round.
The Kings (30-18-7) are second in the Pacific Division, one point behind the Vegas Golden Knights and one point ahead of the third-place Seattle Kraken. They visit the Anaheim Ducks on Friday (9 p.m. ET; ESPN) coming off home victories against the Pittsburgh Penguins and Buffalo Sabres by a combined score of 11-2.
