The 68-year-old was brought in with the aim of keeping the club in the top-flight but was unable to save them, losing three of his four games in charge and drawing the other.
“It has been an honour to manage Leeds United, a great club with an incredible fan base, who deserve to be in the Premier League,” said Allardyce.
“At this stage in my career I am not sure taking on this challenge, which is potentially a long-term project, is something I could commit to, but I wish the club every success for the future and hope the club returns to the Premier League, where they belong.”
Leeds chief executive Angus Kinnear added: “We thank Sam for being brave enough to step in and do all he could to save us.
“Sadly, it was not to be, but Sam, Karl Robinson and Robbie Keane did everything they could to lift the mood at Thorp Arch and Elland Road and for that we are all extremely grateful.”
Relegation ended Leeds’ three-year stay in the Premier League and the club will be desperate to get their next managerial appointment right after sacking Jesse Marsch and Javi Gracia last season, before turning to Allardyce.
Here are some of the leading contenders for the top job at Elland Road:
Steven Gerrard was one of 14 managers sacked by a Premier League club last season after Aston Villa made a poor start to the campaign.
The former Liverpool captain’s reputation took a further hit as his replacement Unai Emery guided Villa away from a relegation battle and into the Europa Conference League.
Prior to joining Villa, though, Gerrard had made a very successful start to his managerial career, winning the Scottish Premiership title with Rangers in 2021 to end Celtic’s nine-year period of dominance, and doing so unbeaten.
The West Brom manager previously worked at Leeds under Marcelo Bielsa as an assistant before moving on to take over Huddersfield Town in 2020.
Carlos Corberan led the Terriers to the Championship play-off final in 2022 before joining Olympiacos last summer and then moving on to West Brom in October after being sacked by the Greek giants.
When Corberan joined the Championship side they were second from bottom after 16 games but they went on to win 10 of their next 13 and in the end, narrowly missed out on a play-off place.
Corberan is contracted to the Baggies until 2027.
Brendan Rodgers was another Premier League boss who lost his job this season after being fired by Leicester in April as they sought – unsuccessfully – to avoid the drop.
Up until that point, Rodgers had enjoyed a successful period at the King Power Stadium, leading the Foxes to their first-ever FA Cup success in 2021 and consecutive fifth-place finishes in the Premier League.
Although Rodgers’ time at Leicester ended in disappointing circumstances, it would be a surprise if his next job was in the Championship given his track record with Celtic, Liverpool and Swansea.
Rodgers has also been linked with Spurs as a replacement for Antonio Conte.
Regis Le Bris
Regis Le Bris is the current manager of Ligue 1 side Lorient who managed to finish the season in the top half of the table for the first time since their promotion in 2020-21.
The Frenchman is far less of a household name compared to other candidates but has impressed in his first job as a senior manager and may provide fresh ideas at Elland Road.
At one point Lorient sat second in the league only behind PSG thanks to the direct transitional play that had shades of Bielsa’s style at Leeds.
How the Leeds faithful would love to see their side playing that brand of football once more.
Lee Bowyer enjoyed the most successful spell of his playing career at Leeds, scoring 55 goals in 265 games for the club and playing a key role as they reached the Champions League semi-final in 2001.
The 46-year-old made a promising start to life in management, steering Charlton to promotion to the Championship via the play-offs before leaving to take charge of Birmingham where things did not go to plan.
Bowyer has been without a job since leaving the Blues last summer.