|Shipyard||Germaniawerft, Kiel (Werk 242)|
|Ordered||15 Nov 1914|
|Laid down||3 Nov 1914|
|Commissioned||23 Mar 1915|
|Successes||4 ships sunk with a total of 10,942 tons. (View ships hit by UB 4)|
|Fate||15 Aug 1915 - Sunk by gunfire from Q-Ship Inverlyon off Yarmouth 5246N 0210E. 15 dead (all hands lost).|
On 10 April, 1915 U-Flottille Flandern claimed its first victim when UB 4 sank a steamer with a torpedo in the North Sea.