Leeds' emphatic 6-0 win over Stoke earlier in the day meant they had to wait and watch on to see if Burnley could create an unassailable gap for the top two sides in the Championship.
Two goals from club captain and top scorer Josh Brownhill were enough to seal the win for Burnley, who have only conceded a mere 15 goals throughout the entire league campaign, with just two more games remaining.
"I'm speechless. All that hard work this season," Brownhill told Sky Sports.
"We've been written off so many times, people calling us boring. We've bored our way to the Premier League.
"It takes a whole team - it's not just a back four, a goalkeeper, it takes everybody."
Both Leeds and Burnley are deadlocked at the top of the table on 94 points, with Leeds boasting a far superior goal difference despite Scott Parker's side's excellent defensive record.
Leeds, who last played in the Premier League in the 2022/23 season, suffered the agony of defeat to Southampton in last season's Championship playoff final at Wembley.
Sheffield United themselves were right in the mix until a recent loss of form, including three consecutive losses, ultimately forcing Chris Wilder's side to settle for a place in the playoffs after suffering defeat.
Along with the Blades, the remaining playoff places are currently being filled by Sunderland, Bristol City and Coventry, although Middlesbrough, Millwall and Blackburn still remain in with an outside chance of scraping in.
Leeds hit Stoke for six
Leeds' German head coach Daniel Farke and his players celebrated in front of their passionate fans at the final whistle, but the champagne was still on ice as they awaited the result from Burnley's match.
Farke, who has previously managed in the Premier League with Norwich, praised the way his team had coped with the pressure.
"To deliver such an emphatic performance is really amazing and all the credit goes to the boys for the way they have handled the situation and the spirit they have shown in recent weeks," he told the BBC.
"It's the fate of a striker that sometimes you have a dry period or a dip in form. Joel had this, but he has worked so hard and got himself out of it.
"In the last few weeks, his performances were better, but the ball didn't want to go in the net. It's a bit like shaking a bottle of ketchup - all of a sudden, everything comes out, and that was a bit the case today."
Leeds wobbled from the start of March, winning just one in six games, raising fears that they would again have to settle for a place in the playoffs.
But they have now won their past four league games.
At the other end of the table, Mustapha Bundu scored twice to keep alive bottom side Plymouth's survival hopes in a 3-1 win against sixth-placed Coventry.
There were also 3-1 victories for relegation-threatened Derby and Luton, while Portsmouth all but sealed their safety with a 1-0 win against 10-man Watford.
Middlesbrough's playoff hopes were dented by a damaging 2-1 loss at Sheffield Wednesday.