|Shipyard||Blohm & Voss, Hamburg (Werk 255)|
|Ordered||22 Jul 1915|
|Launched||16 Nov 1915|
|Commissioned||24 Mar 1916|
|Successes||27 ships sunk with a total of 73,811 tons.|
8 ships damaged with a total of 34,699 tons. (View ships hit by UB 31)
|Fate||2 May 1918 - Lost on a mine in the Strait of Dover at 51°02’N, 01°10’E. 26 dead (all hands lost).|
The wreck of UB 31 clearly establishes that she was mined. The boat's exact date of loss is not known, but would have been between about April 26 and May 3, 1918.
The U-boat's destruction has traditionally been linked to an attack by Lord Leitham, Ocean Roamer, and other patrol vessels on May 2, 1918. This attack though was against the already dead UB 78, which had sank on a mine two weeks earlier.