| Name | Build year | Nationality | Bilde | Loss during WW2 |
|---|---|---|---|---|
| D/S Magdalena | 1923 | Great Britain | Torpedoed, 1940-9-18 | |
| D/S Magnolia | 1909 | Great Britain | ||
| D/S Magog | 1923 | Great Britain | Torpedoed, 1940-7-5 | |
| D/S Maid of Stirling | 1920 | Great Britain | ||
| D/S Maiwara | 1924 | Great Britain | ||
| D/S Manaqui | 1921 | Great Britain | Torpedoed, 1942-3-15 | |
| D/S Manchester Exporter | 1918 | Great Britain | ||
| T/S Manchester Port | 1935 | Great Britain | ||
| T/S Manchester Shipper | 1943 | Great Britain | ||
| T/S Manchester Trader | 1941 | Great Britain | ||
| D/S Mandalay | 1911 | Great Britain | ||
| M/T Mannington | 1943 | Great Britain | ||
| D/S Mapleton | 1909 | Great Britain | ||
| D/S Marconi | 1917 | Great Britain | Torpedoed, 1941-5-21 | |
| D/S Margit | 1924 | Great Britain | Torpedoed, 1944-2-8 | |
| D/S Marion Moller | 1909 | Great Britain | ||
| D/S Marquesa | 1918 | Great Britain | ||
| D/S Marslew | 1926 | Great Britain | Torpedoed, 1941-2-23 | |
| D/S Mary Moller | 1902 | Great Britain | ||
| T/S Mataroa | 1922 | Great Britain | ||
| T/S Mauretania | 1938 | Great Britain | ||
| D/T Melpomene | 1923 | Great Britain | Torpedoed, 1942-3-5 | |
| D/S Merkland | 1934 | Great Britain | ||
| D/S Meroë | 1928 | Great Britain | ||
| M/S Minna | 1939 | Great Britain |