Guard Jamal Crawford scored 16 of his 25 points in the Hawks' 45-points second quarter when Atlanta (50-29) roared to a 59-47 lead. The Hawks had not won 50 games in a season since 1997-98. "He came in and just took over," center Al Horford said of Crawford.
The loss was the fourth in a row for the Raptors, who are vying for the eighth and final Eastern Conference playoff spot.
"It's very satisfying, there's no doubt about it," Hawks coach Mike Woodson told reporters after the milestone win.
Chicago, tied with the Raptors for the final berth, could have broken the deadlock with a win over the lowly New Jersey Nets but lost in double overtime 127-116.
The Raptors play at Chicago on Sunday with Toronto holding the tiebreaker edge should the two teams be tied at the end of the regular season next week.
"We know if we play this way on Sunday, we have a good chance to win," Toronto point guard Jose Calderon said after the loss to the Hawks.
"It's not like (the Bulls) are the best team in the league."
The win was the 11th in a row in Atlanta for the Hawks, their longest home streak since the 1996-97 season.
However, the 50-win mark was more important, said guard Joe Johnson, who had missed the three previous games with a sprained right thumb.
"It feels great," said Johnson. "We've come so far from when I first got here."
(Reporting by Gene Cherry in Salvo, North Carolina; Editing by Peter Rutherford and Ian Ransom)