List of sunken nuclear submarines

A total of nine nuclear submarines have sunk as a consequence of either accident or extensive damage. The United States Navy (USN) have lost two boats while five were lost in the Soviet Navy (one of which sank twice), and two from the Russian Navy. Only three were lost with all hands: the two from the United States Navy (129 and 99 lives lost) and one from the Russian Navy (118 lives lost), accounting for the three largest losses of life in a submarine. All sank as a result of accident except for K-27, which was scuttled in the Kara Sea when proper decommissioning was considered too expensive. The Soviet submarine K-129 carried nuclear ballistic missiles when it was lost with all hands, but as it was a diesel-electric submarine, it is not included in the list.

The two USN submarines belonged to Submarine Force Atlantic, in the U.S. Atlantic Fleet. All five of the Soviet/Russian nuclear submarines that remain sunken belonged to the Northern Fleet, while the refloated K-429 was in the Pacific Fleet.

Of the nine sinkings, two were caused by fires, two by explosions of their weapons systems, two by flooding, one by bad weather, and one by scuttling due to a damaged nuclear reactor. Only USS Scorpion's reason for sinking is unknown. Eight of the submarines are underwater wrecks in the Northern Hemisphere, five in the Atlantic Ocean and three in the Arctic Ocean. The ninth submarine, K-429, was raised and returned to active duty after both of its sinkings.

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