With Tampa Bay's loss to the New York Rangers, the Panthers clinched the division title.
''It works out pretty well,'' said Brian Campbell, who played in his 1,000th game. ''It's a date and a time I won't forget.''
Florida swept the season series against Montreal, winning all four games this season.
Florida set a franchise record with its 99th point in a 4-3 win over Toronto on Monday night.
Luongo got his 34th victory of the season by making several acrobatic saves. The Panthers goaltender robbed Lars Eller without his stick in the second and made a great toe save on Brendan Gallagher later in the same frame.
The 37-year-old got goal support early.
Barkov tied a Panthers franchise record set in 1996 for fastest goal to start a game. Right after the opening faceoff, Barkov took a shovel pass from Jagr at the blue line and beat Condon from the circle on the first shot of the game.
Campbell became the 305th player to reach the 1,000-game plateau and 10th in Panthers franchise history. He's played in 384 consecutive regular season games since 2011.
''I didn't see that coming early in my career, but I'm pretty proud of the fact that I stuck with it,'' said the 36-year-old defenseman who has 487 points in his 16 NHL seasons. ''It's pretty special. I've worked my tail off to get to where I am. Nobody gave me anything to begin with.
Campbell is now headed to the NHL playoffs for the first time since the 2011-12 season, when the Panthers lost in the first round. He won a Stanley Cup with the Blackhawks in 2010.
''He's a marathon man,'' Bjugstad said of Campbell. ''He's a solid defenseman, very underrated and an experienced vet. He's still kicking pretty well for how many games he's played.
''Us younger guys look up to him.''
Galchenyuk got the equalizer for Montreal on the power play at 11:00 of the second period, beating Luongo glove side with a one-timer after a smart no-look pass from Max Pacioretty.
The Habs finished the night 1 for 6 with the man advantage and have scored just five power-play goals in their last 20 games.
It looked like the teams would be deadlocked after 40 minutes, but Bjugstad scored his 15th of the season with 13 seconds remaining in the second frame - a one-timer on the power play.
Montreal went into the third period down a goal despite outshooting Florida 27-11.
''We were happy with our game and we gave ourselves an opportunity in the third period,'' Habs captain Max Pacioretty said. ''We've just got to bury our chances.''
McKegg added Florida's third goal at 8:58 of the final period after scooping up a rebound that Condon failed to secure with his glove. Hudler made it 4-1 with less than 2 minutes remaining.
Called up from the St. John's IceCaps on Sunday, enforcer John Scott made his debut for the Canadiens. Scott finished with a minus-1 rating and 2 penalty minutes in 9:00 of ice time.
NOTES: Rookie defenseman Ryan Johnston made his NHL debut. Johnston is the 15th defenseman to play for Montreal this season. ... Stefan Matteau and Mike Brown were healthy scratches for the Canadiens. ... The Habs announced Brett Lernout (knee) would not play again this season.