In
| Player | Team | Date | Fee |
|---|---|---|---|
| Bjarni Vidarsson | FH | 19 May 2004 | Undisclosed |
| Marcus Bent | Ipswich Town | 23 June 2004 | £450,000 |
| Tim Cahill | Millwall | 23 July 2004 | £2,000,000 |
| Eddy Bosnar | Sturm Graz | 3 August 2004 | Free |
| Johan Troest Davidsen | NSI Runavik | 14 October 2004 | Undisclosed |
| James Beattie | Southampton | 4 January 2005 | £6,000,000 |
| Guillaume Plessis | Lens | 28 January 2005 | Free |
| Mikel Arteta | Real Sociedad | 31 January 2005 | Loan to end of the season |
| Total (initial fees only): | £8,450,000 | ||
- Johan Troest Davidsen (NSI Runavik) – Originally on trial.
- Guillaume Plessis (Lens) – Originally on trial.
Out
| Player | Team | Date | Fee |
|---|---|---|---|
| Alan Moogan | Released | 1 July 2004 | |
| Alex Nyarko | Released | 1 July 2004 | |
| Brian Moogan | Released | 1 July 2004 | |
| Craig Garside | Released | 1 July 2004 | |
| Michael Symes | Released | 1 July 2004 | |
| Patrizio Pascucci | Released | 1 July 2004 | |
| Paul Gerrard | Released | 1 July 2004 | |
| Scot Gemmill | Released | 1 July 2004 | |
| Scott Brown | Released | 1 July 2004 | |
| Steve Simonsen | Released | 1 July 2004 | |
| Steven Schumacher | Released | 1 July 2004 | |
| Anthony Barry | Coventry City | 1 July 2004 | Free |
| Joey Jones | Macclesfield Town | 1 July 2004 | Free |
| Niclas Alexandersson | IFK Gothenburg | 1 July 2004 | Free |
| David Unsworth | Portsmouth | 12 July 2004 | Free |
| Tomasz Radzinski | Fulham | 23 July 2004 | £1,750,000 |
| Tobias Linderoth | Copenhagen | 30 July 2004 | £1,750,000 |
| Wayne Rooney | Manchester United | 31 August 2004 | £20,000,000 (+£7,000,000 add-ons) |
| Anthony Gerrard | Accrington Stanley | 6 September 2004 | 1-month loan |
| Peter Clarke | Blackpool | 17 September 2004 | 1-month loan |
| Peter Clarke | Blackpool | 23 September 2004 | £150,000 |
| Kevin Campbell | West Bromwich Albion | 10 January 2005 | Free |
| Thomas Gravesen | Real Madrid | 14 January 2005 | £2,500,000 |
| Danny Fox | Stranraer | 2 February 2005 | Loan to end of the season |
| Nick Chadwick | Plymouth Argyle | 8 February 2005 | £250,000 |
| Iain Turner | Doncaster Rovers | 18 March 2005 | Loan to end of the season |
| Anthony Gerrard | Walsall | 24 March 2005 | Loan to end of the season |
| Total (initial fees only): | £26,400,000 | ||
- Alan Moogan (Released) – Eventually retired due to injury problems before coming out of retirement to join Burscough in 2006.
- Alex Nyarko (Released) – Eventually joined IK Start on 1st March 2005.
- Brian Moogan (Released) – Eventually joined Lancaster City in November 2004.
- Craig Garside (Released) – Eventually joined Colwyn Bay ahead of the 2004/05 season.
- Michael Symes (Released) – Eventually joined Bradford City on 30th July 2004.
- Patrizio Pascucci (Released) – Eventually joined Sora ahead of the 2004/05 season.
- Paul Gerrard (Released) – Eventually joined Nottingham Forest on 2nd July 2004.
- Scot Gemmill (Released) – Eventually joined Leicester City on 5th August 2004.
- Scott Brown (Released) – Eventually joined Bristol City on 10th August 2004.
- Steve Simonsen (Released) – Eventually joined Stoke City on 8th July 2004.
- Steven Schumacher (Released) – Eventually joined Bradford City on 30th July 2004.
- Joey Jones (Macclesfield Town) – Deal agreed on 18th May 2004.
| Income | £26,400,000 |
| Expenditure | £8,450,000 |
| Net Spend | -£17,950,000 |