Ships hit by U-4
See the profile page for U-4
| Date | U-boat | Commander | Name of ship | Tons | Nat. | Convoy | ||
| 22 Sep, 1939 | U-4 | Harro von Klot-Heydenfeldt | Martti Ragnar | 2.262 |  | fi | ||
| 23 Sep, 1939 | U-4 | Harro von Klot-Heydenfeldt | Walma | 1.361 | | fi | ||
| 24 Sep, 1939 | U-4 | Harro von Klot-Heydenfeldt | Gertrud Bratt | 1.510 |  | sw | ||
| 10 Apr, 1940 | U-4 | Hans-Peter Hinsch |  | HMS Thistle (N 24) | 1.090 |  | br | |
| 6.223 | ||||||||
| 4 ships sunk (6.223 tons).
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