List of successful U-boats contains lists of the most successful German U-boats in the two World Wars based on total tonnage.
This list contains the 5 most successful German U-boats during the First World War based on total tonnage. Only sunk commercial vessels are included, not military (warships) nor damaged ships.
|SM U-35||Type U 31||3 November 1914||505,119||220||17||Surrendered, 26 November 1918||Waldemar Kophamel|
Lothar von Arnauld de la Perière
Ernst von Voigt
Heino von Heimburg
|SM U-39||Type U 31||13 January 1915||404,961||151||19||Surrendered, 22 March 1919||Hans Kratzsch|
|SM U-38||Type U 31||15 December 1914||288,059||135||17||Surrendered, 23 February 1919||Max Valentiner|
Hans Heinrich Wurmbach
|SM U-34||Type U 31||5 October 1914||257,652||119||17||Missing, 9 November 1918||Claus Rücker|
|SM U-53||Type U 51||22 April 1916||224,314||87||13||Surrendered, 1 December 1918||Hans Rose|
Otto von Schrader
This list contains the 10 most successful German U-boats during the Second World War based on total tonnage. Both commercial and military vessels (warships) are included but only sunk ships are included, not damaged ships.
|U-48||VIIB||22 April 1939||300,537||51||12||Scuttled, 3 May 1945||Herbert Schultze|
|U-99||VIIB||18 April 1940||244,658||38||8||Scuttled, 17 March 1941 after depth charging by HMS Walker.||Otto Kretschmer|
|U-103||IXB||18 April 1940||237,596||45||11||Decommissioned March 1944. Sunk by bombs in Kiel, 15 April 1945.||Viktor Schütze|
|U-124||IXB||11 June 1940||225,637||48||11||Lost with all hands, 2 April 1943 after depth charging by HMS Stonecrop and HMS Black Swan.||Georg-Wilhelm Schulz|
|U-123||IXB||30 May 1940||222,705||44||12||Decommissioned 17 June 1944. Scuttled in port, 19 August 1944. Refloated and taken into French service as Blaison.||Karl-Heinz Moehle|
Horst von Schroeter
|U-107||IXB||8 October 1940||217,786||39||13||Lost with all hands 18 August 1944 after depth charging by a Sunderland of 201 Squadron RAF.||Günter Hessler|
|U-37||IX||4 August 1938||202,467||55||11||Scuttled, 8 May 1945||Heinrich Schuch|
Asmus Nicolai Clausen
|U-66||IXC||20 March 1940||200,021||33||9||Sunk 6 May 1944 by Grumman F4F Wildcats and Grumman TBF Avengers of USS Block Island, rammed by destroyer escort USS Buckley.||Richard Zapp|
|U-68||IXC||11 February 1941||197,998||33||10||Sunk 10 April 1944, depth charges and rockets fired by F4F Wildcats and TBM Avengers of USS Guadalcanal.||Karl-Friedrich Merten|
|U-47||VIIB||17 December 1938||191,919||31||10||Missing with all hands, on or about 7 March 1941 while patrolling south of Iceland between 59 deg and 62 deg north.