| Season: | 2003–04 |
| League Topscorer: | Jimmy Floyd Hasselbaink (13) |
| Season Topscorer: | Jimmy Floyd Hasselbaink (18) |
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| Nextseason: | 2004–05 |
The 2003–04 season was Chelsea F.C.'s 12th consecutive season in the Premier League and 98th year as a club. Manager Claudio Ranieri was sacked on 31 May 2004 and was replaced by José Mourinho. In July 2003, long-time chairman Ken Bates sold the club to Russian billionaire Roman Abramovich.
Chelsea finished the season as runners-up in the Premier League. In the Champions League Chelsea reached the semi-finals against AS Monaco, but failed to reach the final, losing 5–3 on aggregate to the French side. They also exited the FA Cup in the fifth round to Arsenal and the Carling Cup in the quarter-finals to Aston Villa.
The team kit was produced by Umbro. The shirt sponsor was Emirates Airline; the kit bore the "Fly Emirates" logo. Chelsea's home kit was all blue with a white collar. Their new away kit was all white with black and blue stripes down the center. Last season's away kit (all black with blue accents) was retained as the club's third kit.
Squad at end of season
| Pos | Player | From | data-sort-type="currency" | Fee | Date | |
|---|---|---|---|---|---|---|
| 1 | GK | Free[1] | 1 July 2003 | |||
| 31 | GK | Free | 1 July 2003 | |||
| 2 | DF | £6,000,000[2] | 15 July 2003 | |||
| 14 | MF | £7,000,000[3] | 16 July 2003 | |||
| 18 | DF | £7,000,000[4] | 21 July 2003 | |||
| 11 | MF | £17,000,000[5] | 21 July 2003 | |||
| 10 | MF | £6,600,000[6] | 6 August 2003 | |||
| 20 | MF | £15,000,000[7] | 6 August 2003 | |||
| 7 | FW | £15,800,000[8] | 12 August 2003 | |||
| 5 | MF | £3,450,000[9] | 25 August 2003 | |||
| 21 | FW | £16,800,000[10] | 26 August 2003 | |||
| 34 | GK | £500,000[11] | 29 August 2003 | |||
| 4 | MF | £16,000,000[12] | 31 August 2003 | |||
| 19 | MF | £10,000,000[13] | 30 January 2004 |
| Pos | Player | To | Fee | Date | ||
|---|---|---|---|---|---|---|
| 17 | DF | Unattached | Released | 3 June 2003 | ||
| 25 | FW | Free[14] | 2 July 2003 | |||
| 20 | MF | Free[15] | 18 July 2003 | |||
| 14 | DF | £500,000 | 21 July 2003 | |||
| 1 | GK | Undisclosed[16] | 1 August 2003 |
Summer: £111,150,000
Winter: £10,000,000
Total: £121,150,000
Summer: £500,000
Winter: £0
Total: £500,000
Summer: £110,650,000
Winter: £10,000,000
Total: £120,650,000
See main article: 2003–04 FA Premier League.
See main article: 2003–04 UEFA Champions League.
See main article: 2003–04 UEFA Champions League knockout stage.
See main article: 2003–04 FA Cup.
See main article: 2003–04 Football League Cup.
|}Statistics taken from http://www.soccerbase.com/squad_season.sd?teamid=536 and http://www.11v11.com/teams/chelsea/tab/players/season/2004. Squad details and shirt numbers from http://www.zanziball.it/en/28/6808.html and http://www.eufo.de/football/eng/2003/chela_fc.htm.