List of successful U-boats contains lists of the most successful German

U-boat U-boats were naval submarines operated by Germany, particularly in the First and Second World Wars. Although at times they were efficient fleet weapons against enemy naval warships, they were most effectively used in an economic warfare ro ...

s in the two

World War A world war is an international conflict which involves all or most of the world's major powers. Conventionally, the term is reserved for two major international conflicts that occurred during the first half of the 20th century, World WarI (1914 ...

s based on total

tonnage Tonnage is a measure of the cargo-carrying capacity of a ship, and is commonly used to assess fees on commercial shipping. The term derives from the taxation paid on ''tuns'' or casks of wine. In modern maritime usage, "tonnage" specifically r ...

World War I

This list contains the 5 most successful German U-boats during the

First World War World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

based on total tonnage. Only sunk commercial vessels are included, not military (

warships A warship or combatant ship is a naval ship that is built and primarily intended for naval warfare. Usually they belong to the armed forces of a state. As well as being armed, warships are designed to withstand damage and are usually faster an ...

) nor damaged ships.

World War II

This list contains the 10 most successful German U-boats during the

Second World War World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposi ...

based on total

. Both commercial and military vessels (

) are included but only sunk ships are included, not damaged ships.

References

uboat.net webpage about the most successful U-Boats of World War I
- This list does not include military vessels.

- This list does not include military vessels and is therefore not identical to list above.
uboataces.com webpages about the most successful U-Boats of World War II
- This list seems to miss ''U-123'' in top 5 list. {{Uboat U-boats Submarines of Germany

U-Boats U-boats were naval submarines operated by Germany, particularly in the First and Second World Wars. Although at times they were efficient fleet weapons against enemy naval warships, they were most effectively used in an economic warfare rol ...