| 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 | ||
| MacKelsey | Unknown | 1884 | Unknown | 1885 | |||
| MacLaren | D | Plymouth Argyle | £8,000 | 2 January 1965 | Southampton | £5,000 | 24 September 1966 |
| MacLaren | WS | Unknown | 24 June 1981 | Hibernian [Sco] | Loan | 16 August 1982 | |
| Released | 8 October 1982 | ||||||
| Madden | LD | Sheffield Wednesday | Free | 15 August 1991 | Darlington | Free | 3 September 1993 |
| Maguire | JE | Willington | Fee Unknown | 8 November 1935 | Sunderland | Guest | 1944-45 |
| Hibernian [Sco] | Fee Unknown | 14 April 1945 | |||||
| Mahon | G | Juniors | NA | 1 August 1995 | Hereford United | Free | 12 July 1996 |
| Maierhofer | S | Rapid Vienna [Aus] | £1,800,000 | 31 August 2009 | Bristol City | Loan | 15 March 2010 |
| RB Salzburg [Aus] | £1,030,000 | 23 August 2011 | |||||
| Malcolm | KC | Juniors | NA | 1 March 1943 | Released | NA | |
| Malone | SL | Juniors | NA | 1 July 2008 | Southend United | Loan | 1 August 2009 |
| Burton Albion | Loan | 22 October 2010 | |||||
| Bournemouth | £150,000 | 1 July 2011 | |||||
| Malpass | AW | Wednesbury Old Athletic | Fee Unknown | 1 August 1891 | Retired | 1899 | |
| Mancienne | MI | Chelsea | Loan | 27 October 2008 | NA | ||
| Chelsea | Loan | 13 August 2009 | NA | ||||
| Chelsea | Loan | 26 August 2010 | NA | ||||
| Mannion | GP | Juniors | NA | 27 November 1957 | Norwich City | £17,000 | 31 August 1961 |
| Marcal | F | Olympique Lyon [Fra] | £1,800,000 | 6 September 2020 | Botafogo [Bra] | Free | 19 July 2022 |
| Mardenborough | SA | Coventry City | Free | 20 September 1983 | Cambridge United | Loan | 23 February 1984 |
| Swansea City | Free | 24 August 1984 | |||||
| Margreitter | G | Austria Vienna [Aus] | £2,250,000 | 24 August 2012 | Copenhagen [Den] | Loan | 2 September 2013 |
| Chesterfield | Loan | 11 September 2014 | |||||
| 1FC Nuremburg [Ger] | Free | 24 August 2015 | |||||
| Marques | CF | Juniors | NA | 1 July 2020 | B Sad | Loan | 31 August 2021 |
| Forest Green Rovers | Loan | 1 September 2022 | |||||
| Yverdon-Sport | Free | 7 September 2023 | |||||
| Marr | A | Coventry City | Fee Unknown | 6 May 1913 | Gateshead | Free | 1914 |
| Marsden | C | Huddersfield Town | £250,000 | 11 January 1994 | Notts County | £250,000 | 15 November 1994 |
| Marsden | F | Accrington Stanley (1) | Fee Unknown | 29 January 1935 | Bournemouth & Boscombe Athletic | Fee Unknown | 9 May 1936 |
| Marsh | J | Unknown | 10 August 1936 | Newport County | Fee Unknown | 15 September 1936 | |
| Marsh | R | Unknown | Exeter City | 7 November 1941 | |||
| Marshall | AJ | Ipswich Town | Loan | 12 November 2003 | NA | ||
| Marshall | B | Blackburn Rovers | £1,260,000 | 31 January 2017 | Millwall | Loan | 31 January 2018 |
| Norwich City | £1,530,000 | 29 February 2024 | |||||
| Marshall | GH | Southend United | Fee Unknown | 14 May 1919 | Walsall | Fee Unknown | 1 March 1924 |
| Marshall | JG | Norwich City | Fee Unknown | 29 April 1939 | Workington | Fee Unknown | Aug-46 |
| Marshall | WH | Southport | Fee Unknown | 16 March 1928 | Port Vale | Fee Unknown | 15 March 1930 |
| Marson | F | Darlaston | Fee Unknown | 16 May 1923 | Sheffield Wednesday | Fee Unknown | 15 June 1925 |
| Martin | DK | Belfast Celtic | £7,250 (combined) | 14 December 1934 | Nottingham Forest | Fee Unknown | 30 June 1936 |
| Martin | JC | Aberdare Athletic | Fee Unknown | 18 October 1923 | Reading | Fee Unknown | 22 July 1924 |
| Martin | T | Newport County | Fee Unknown | 3 May 1930 | Swansea Town | Fee Unknown | 21 July 1932 |
| Martin | TW | Juniors | Fee Unknown | 1940 | Millwall | Guest | 1942-43 |
| Martinez | E | Arsenal | Loan | 10 August 2015 | NA | ||
| Mason | C | School | Fee Unknown | 1880 | Retired | May 1892 | |
| Mason | J | Blakenhall St Lukes | Fee Unknown | July 1885 | Willenhall Swifts | Fee Unknown | May 1891 |
| Mason | J | Worcester City | Fee Unknown | 17 January 1908 | Bristol Rovers | Fee Unknown | 4 May 1909 |
| Mason | J | Cardiff City | £3,500,000 | 28 January 2016 | Burton Albion | Loan | 23 August 2017 |
| Colorado R [USA] | Loan | 20 February 2018 | |||||
| Portsmouth | Loan | 31 August 2018 | |||||
| MK Dons | Released | 31 January 2019 | |||||
| Mason | RH | Juniors | NA | 30 May 1953 | Chelmsford City | Free | 12 July 1962 |
|
