SM U-25 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-25 was engaged in the naval warfare and took part in the First Battle of the Atlantic.
| Date | Name | Nationality | Tonnage[1] | Fate[2] | |
|---|---|---|---|---|---|
| 7 June 1915 | Glittertind |  Norway | 717 | Sunk | |
| 7 June 1915 | Nottingham |  United Kingdom | 165 | Sunk | |
| 7 June 1915 | Pentland | United Kingdom | 204 | Sunk | |
| 7 June 1915 | Saturn | United Kingdom | 183 | Sunk | |
| 7 June 1915 | Velocity | United Kingdom | 186 | Sunk | |
| 9 June 1915 | Cardiff | United Kingdom | 163 | Sunk | |
| 9 June 1915 | Castor | United Kingdom | 182 | Sunk | |
| 9 June 1915 | J. Leyman | United Kingdom | 197 | Sunk | |
| 9 June 1915 | Tunisian | United Kingdom | 211 | Sunk | |
| 4 July 1915 | Sunbeam | United Kingdom | 132 | Sunk | |
| 8 July 1915 | Anna | 2,000 | Sunk | ||
| 8 July 1915 | Guido | United Kingdom | 2,093 | Sunk | |
| 9 July 1915 | Nordaas | Norway | 1,111 | Sunk | |
| 11 July 1915 | Hainton | United Kingdom | 156 | Sunk | |
| 11 July 1915 | Syrian | United Kingdom | 176 | Sunk | |
| 11 July 1915 | Fleetwood | United Kingdom | 163 | Damaged | |
| 6 August 1915 | Maj |  Sweden | 920 | Sunk | |
| 7 August 1915 | Norman | Norway | 1,060 | Sunk | |
| 10 August 1915 | Aura | Norway | 396 | Sunk | |
| 14 August 1915 | Albis | Norway | 1,381 | Sunk | |
| 17 August 1915 | Mineral | Norway | 649 | Sunk | |
| 19 August 1915 | Bras | Norway | 1,863 | Sunk |