| A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
| From | Cost | Date | To | Cost | Date | ||
| Oakes | M C | Aston Villa | £500,000 | 29 October 1999 | Cardiff City | Free | 7 July 2007 |
| O’Connor | J P | Quarry Bank Rangers | Fee Unknown | 7 December 1923 | Gillingham | Fee Unknown | August 1923 |
| O’Connor | K J A | Juniors | NA | 12 July 2003 | Stockport County Telford |
Loan Released |
23 March 2006 1 July 2008 |
| Odofin | H | Barnet | Fee Unknown | 1 August 2016 | Eastleigh Northampton Town |
Loan Free |
15 December 2016 9 July 2018 |
| O’Donnell | F J | Aston Villa | Guest | 1941-42 | NA | ||
| Ofosu-Ayeh | P | Eintracht Braunschweig [Ger] | Free | 20 June 2017 | Hansa Rostock [Ger] Wurzburger K [Aus] Halmstads BK [Swe] |
Loan Loan Released |
1 December 2018 31 January 2019 22 August 2020 |
| O’Grady | M | Leeds United | £80,000 | 24 September 1969 | Birmingham City Rotherham United |
Loan Fee Unknown |
17 February 1972 8 November 1972 |
| O’Hara | G J | Juniors | NA | 12 July 1973 | Hereford United | Released | 19 January 1978 |
| O’Hara | J D | Tottenham Hotspur Tottenham Hotspur |
Loan £5,000,000 |
30 January 2011 21 June 2011 |
Blackpool | Free | 5 November 2014 |
| Ojo | O B | Liverpool | Loan | 3 August 2015 | NA | ||
| Okoronkwo | I | Shaktar Donetsk [Ukr] | Free | 8 January 2003 | Terek Grozny [Rus] | Released | 1 June 2004 |
| Oldershaw | W | 1889 | 1890 | ||||
| Oldfield | J S | Huddersfield Town | £20,000 | 24 December 1969 | Crewe Alexandra Bradford City |
Loan Fee Unknown |
4 November 1971 31 December 1971 |
| Oldroyd | D R | Everton | Free | 21 August 1986 | Chester City | Released | 10 February 1987 |
| Oliphant | D | Juniors | NA | June 1959 | Carlisle United | Fee Unknown | 2 December 1960 |
| Olofinjana | S G | Brann Bergen [Nor] | £1,700,000 | 1 July 2004 | Stoke City | £3,000,000 | 26 July 2008 |
| O’Mahoney | M | Southport | £1,000 | 17 May 1935 | Newport County | Fee Unknown | 16 March 1936 |
| O’Neill | J | Amateur | NP | 10 December 1942 | Unknown | 1945 | |
| Oniangue | P | Stade Reims [Fra] | £2,000,000 | 16 August 2016 | SC Bastia [Fra] SCO Angers [Fra] SM Caen [Fra] |
Loan Loan £500,000 |
16 January 2017 4 January 2018 12 July 2018 |
| Ordish | C S | Chesterfield | Fee Unknown | 1 May 1936 | Reading | Fee Unknown | 12 February 1938 |
| Osborn | S E | Queens Park Rangers | £1,000,000 | 22 December 1995 | Tranmere Rovers Port Vale |
Loan Free |
22 March 2001 5 September 2001 |
| O’Shaughnessy | J P D | Burnley | Fee Unknown | July 2019 | Macclesfield Town | Released | 29 January 2023 |
| Otosowie | E | Juniors | NA | 1 July 2019 | Bruges [Bel] | £3,600,000 | 20 August 2021 |
| Owen | B E | Colchester United | Fee Unknown | 20 January 1972 | Retired | May 1973 | |
| Owen | H | Apprentice | NA | NA | Liverpool | £800,000 | 25 July 2023 |
| Owen | I L T | Crewe Alexandra | Fee Unknown | 25 April 1899 | Crewe Alexandra | Fee Unknown | 16 July 1900 |
| Owen | I L T | Amateur | NP | 22 July 1943 | 1944 | ||
| Owen | W | Loughborough Town | Fee Unknown | 24 August 1895 | Everton | Fee Unknown | 4 May 1898 |