The 31-year-old defenseman, who could have become an unrestricted free agent after this season, has scored nine points (two goals, seven assists) in 45 games. He is also tied for the NHL lead with 110 blocks with Mario Ferraro of the San Jose Sharks.
Selected by the Buffalo Sabres in the third round (No. 66) of the 2009 NHL Draft, McNabb has scored 107 points (22 goals, 85 assists) in 552 regular-season games with the Sabres, Los Angeles Kings and Golden Knights, including 57 points (15 goals, 42 assists) in 314 games since being selected by Vegas in 2017 NHL Expansion Draft.
Forward Michael Amadio and goalie Logan Thompson also signed contracts with the Golden Knights on Sunday.
Amadio received a two-year, $1.525 million contract (average annual value of $762,500). Thompson signed a three-year, $2.3 million contract (AAV of $766,667). Each could have become a restricted free agent after the season.
Amadio has scored seven points (four goals, three assists) in 25 games with the Golden Knights since being claimed off waivers from the Toronto Maple Leafs on Oct. 30. A third-round pick (No. 90) by the Kings in the 2014 NHL Draft, the 25-year-old has scored 47 points (20 goals, 27 assists) in 201 games with Los Angeles, the Ottawa Senators, Toronto and Vegas.
Thompson made his first NHL start for Vegas on Jan. 4, making 23 saves in a 3-2 loss to the Nashville Predators. Signed by the Golden Knights as a free agent on July 13, 2020, the 24-year-old is 11-7-3 with a 2.62 goals-against average and .928 save percentage in 21 games for Henderson of the American Hockey League this season.
Vegas (26-16-3) is currently first in the Pacific Division and is next scheduled to play the Buffalo Sabres on Tuesday (10 p.m. ET; ESPN+, HULU, NHL LIVE).