He spent the 1980s as a journeyman player, spending time with Sunderland, Millwall, Tampa Bay Rowdies, Coventry City, Huddersfield Town, Bolton Wanderers (for a second spell), Preston North End, and West Bromwich Albion (also working as assistant manager).

In September 2016, undercover Daily Telegraph reporters posing as businessmen recorded him offering to help them to get around FA third party ownership rules and provisionally agreeing a £400,000 contract.

[45] Bolton fans gave him the nickname "Super Sam Bionic Man" due to his tough tackling approach and the way he quickly got up after heavy collisions whilst the opposition player would be left flat on the ground.

[56] On 19 July 1994[57] Blackpool, West Lancashire derby rivals to Preston North End, appointed Allardyce as their new manager following the departure of Billy Ayre, agreeing a salary of £18,000 a year.

[58] He signed defender Darren Bradshaw, midfielder Micky Mellon and spent a club record £245,000 on Andy Morrison, who Allardyce described as a "horrible in-your-face" centre-back and a "complete nutter".

[59] He also changed the club's backroom staff, hiring Bobby Saxton as his assistant, promoting player Phil Brown to a coaching role, and appointing Mark Taylor as physio, who would follow Allardyce to Blackburn and Newcastle.

I walked out of there with £10,000, no job, and desperately worried that my reputation would be damaged forever.In January 1997, Allardyce returned to football as manager of struggling Division Two club Notts County.

[69] However, he held on to his job and led the club to promotion as champions of Division Three at the end of the 1997–98 season, built upon a three-man defence and a mid-season run of ten consecutive wins.

[73] Allardyce was appointed manager of Bolton Wanderers following Colin Todd's departure, who had resigned in protest at the sale of Per Frandsen as the club attempted to raise funds for the new Reebok Stadium.

[74] He inherited a talented squad, which included Eiður Guðjohnsen, Jussi Jääskeläinen, Mark Fish, Claus Jensen, Dean Holdsworth, Bo Hansen, Michael Johansen, and Ricardo Gardner.

[80] On the playing front he spent £400,000 on striker Michael Ricketts and £1.5 million to bring back Frandsen from Blackburn and also signed utility player Ian Marshall and Bradford City loanee Isaiah Rankin.

[82] Bolton reached the play-off final at the Millennium Stadium in 2000–01, where they beat Preston North End 3–0 to achieve promotion to the Premier League after a three-year absence.

[87] However their form dropped, and so in the January transfer window Allardyce brought in Danish midfielder Stig Tøfting, German striker Fredi Bobic (on loan), and World Cup-winning attacker Youri Djorkaeff.

[89] Allardyce managed to sign another big name on a free transfer for the 2002–03 season, bringing in 28-year-old Nigeria captain Jay-Jay Okocha, who four years previously had been purchased by Paris Saint-Germain for £14 million.

[93] Looking to avoid another relegation battle, Allardyce made some signings in preparation for the 2003–04 season, the most significant of which were Brazilian defender Emerson Thome, Greece international Stelios Giannakopoulos, and target-man striker Kevin Davies.

[101] Allardyce's success with Bolton resulted in the FA putting him on a short-list of four people to succeed Sven-Göran Eriksson as England manager after the 2006 FIFA World Cup, alongside Alan Curbishley, Steve McClaren and Martin O'Neill.

Keen to strengthen Bolton for a European push in the 2006–07 season, Allardyce signed France international striker Nicolas Anelka from Fenerbahçe for a club record £8 million.

[108] On 29 April 2007, Allardyce resigned with the club in fifth place with two games of the season left to play, and the following day, his assistant Sammy Lee was announced as his replacement.

[119] On 17 December 2008, Allardyce was appointed as manager of Blackburn Rovers on a three-year contract, succeeding Paul Ince, who left the club in 19th place with just three wins from 17 games.

[122][123] Blackburn were forced to sell talismanic Paraguay striker Roque Santa Cruz to Manchester City and defender Stephen Warnock to Aston Villa for a combined £21.5 million to balance the books.

[143][144][145][146] He concluded his summer transfer window signings on deadline day by bringing in midfielders David Bentley from Tottenham Hotspur and Henri Lansbury from Arsenal, both on season-long loans, as well as utility man Guy Demel from Hamburg for an undisclosed fee.

[168] The following month some supporters hung a banner bearing the legend "Fat Sam Out" outside the mansion owned by club chairman, David Sullivan, in Theydon Bois, Essex.

[172] In October 2014, pundits like BBC's Robbie Savage were commenting about the team's "more attractive and attacking playing style"[173] or "the statistics [that] show the progress that West Ham have made in the last few months.

[190] He won his first and only game in charge on 4 September, as an Adam Lallana goal deep into injury-time was enough to beat Slovakia on the opening day of qualification for the 2018 FIFA World Cup.

[204][205] His time as manager began with West Brom losing 3–0 at home to local rivals Aston Villa on 20 December with defender Jake Livermore being sent-off in the first half for a bad foul on Jack Grealish.

[243][244] On 14 November 2021, Allardyce took part in a charity match to help raise money for the mother of Bolton Wanderers player Gethin Jones, who had been diagnosed with motor neuron disease.

[248] While he also stated he was going to sue the broadcaster to clear his name,[249] Allardyce failed to issue libel proceedings as he was advised that suing for damage to reputation was a costly and time-consuming process.

[252] In February 2014, Daniel Taylor, chief football writer for The Guardian and The Observer, wrote that West Ham player and England prospect Ravel Morrison felt he had come "under considerable pressure" from Allardyce to sign up with football agent Mark Curtis, who represented Allardyce himself and a number of other West Ham players, including Kevin Nolan, James Tomkins, Jack Collison, Matt Jarvis, Andy Carroll, and Jussi Jääskeläinen.

[253] Curtis responded to the allegations by saying they were "nonsense", while Allardyce talked of Morrison complaining about "a groin injury" while the club's medical staff could find "no problem",[253] and made a reference to the player's "disciplinary issues in the past".

[257] Robert Sullivan, Director of Strategy at the FA, later confirmed to the Commons Culture, Media and Sport Select Committee that Allardyce's comments were "a factual, correct statement around the laws of the English game and having third-party ownership".