| 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 | ||
| Morgan | R | Accrington Stanley (1) | Guest | 1941-42 | Bournemouth & BA | Fee Unknown | 1 June 1935 |
| Morgan | W A | Juniors | NA | 27 April 1905 | 28 April 1905 | ||
| Morris | W W | Halesowen Town | £100 | 1 May 1933 | Retired | NA | 1 June 1947 |
| Morrissey | J J | Everton | Free Agent | 2 August 1985 | Tranmere Rovers | £8,000 | 2 October 1985 |
| Mosquera | Y | Atletico Nacional [Col] | Undiclosed | 17 June 2021 | Cincinnati [USA] | Loan | 2 February 2023 |
| Villarreal [Spa] | Loan | 23 January 2023 | |||||
| Moss | C A | Juniors | NA | 21 March 1979 | Worcester City | Released | 1 March 1982 |
| Moss | P M | Northfield Juniors | Fee Unknown | 20 July 1976 | Hull City | Loan | 6 September 1979 |
| Hull City | Fee Unknown | 4 October 1979 | |||||
| Moulden | L | Manchester City | Free | 1 July 2021 | Ebbsfleet | Loan | 31 January 2022 |
| Solihull Moors | Loan | 1 July 2022 | |||||
| Rochdale | Loan | 13 July 2023 | |||||
| Northampton T | Loan | 16 January 2023 | |||||
| Crystal Palace | Free | 22 August 2024 | |||||
| Mountfield | D N | Aston Villa | Loan | 7 November 1991 | Carlisle United | Free | 3 August 1994 |
| Aston Villa | £150,000 | 3 February 1992 | |||||
| Moutinho | J | Monaco [Fra] | £5,040,000 | 24 July 2018 | Released | 1 July 2023 | |
| Mouyokolo | S | Hull City | £2,700,000 | 18 June 2010 | Sochaux [Fra] | Loan | 16 July 2011 |
| Celtic [Sco] | Released | 30 January 2013 | |||||
| Mujangi Bia | G | RSC Charleroi [Bel] | Loan | 30 June 2011 | NA | ||
| Mulgrew | C P | Celtic [Sco] | Undisclosed | 8 September 2006 | Aberdeen [Sco] | £150,000 | 15 January 2008 |
| Mulholland | T | Belfast Distillery | Fee Unknown | 2 November 1912 | Brewood | Fee Unknown | 27 March 1905 |
| Mullen | J | Juniors | NA | 9 January 1940 | Newcastle United | Guest | 1942-43 |
| Reading | Guest | 1942-43 | |||||
| Newcastle United | Guest | 1943-44 | |||||
| Darlington | Guest | 1945-46 | |||||
| Middlesbrough | Guest | 1945-46 | |||||
| Retired | 1 June 1960 | ||||||
| Mulligan | G T | Juniors | NA | 1 August 2004 | Rushden & Diamonds | Loan | 13 October 2004 |
| Sheffield United | Free | 3 July 2005 | |||||
| Mulraney | A A | Ipswich Town | Guest | 1942-43 | NA | ||
| Mulvaney | J | Dumbarton [Sco] | Guest | 1943-44 | NA | ||
| Munetsi | M N | Stade Reims [Fra] | £18,000,000 | 3 February 2025 | |||
| Munro | F M | Aberdeen [Sco] | £60,000 | 5 January 1968 | Celtic [Sco] | £20,000 | 30 December 1977 |
| Murray | J R | Juniors | NA | 24 November 1953 | Manchester City | £27,000 | 7 November 1963 |
| Murray | M W | Juniors | NA | 1 August 1997 | Kingstonian | Loan | 20 October 2000 |
| Tranmere Rovers | Loan | 21 March 2006 | |||||
| Hereford United | Loan | 14 November 2008 | |||||
| Retired | 26 August 2010 | ||||||
| Muscat | K V | Crystal Palace | £200,000 | 21 October 1997 | Rangers [Sco] | Free | 1 July 2002 |
| Mutch | A T | Southport | Fee Unknown | 25 February 1986 | Swindon Town | £250,000 | 16 August 1993 |
| Myers | J H | Barnsley | Combined (Fee Unknown) | 20 June 1938 | Cardiff City | Fee Unknown | 14 May 1940 |
| Mynard | L D | Juniors | NA | 22 May 1945 | Notts County | Guest | 1944-45 |
| Derby County | Exchange | 13 July 1949 |
|
