Nine nuclear submarines have tragically sunk, either due to accidents or deliberate scuttling. Among them, five belonged to the Soviet Navy (one sinking occurred twice), two to the Russian Navy, and two to the United States Navy (USN). The causes of sinking varied: two were a result of fires, two due to weapon explosions, two from flooding, one attributed to severe weather, and one purposefully scuttled due to a damaged nuclear reactor.

The two USN submarines were part of the Submarine Force Atlantic in the U.S. Atlantic Fleet. All five of the remaining sunken Soviet/Russian nuclear submarines were affiliated with the Northern Fleet, while the refloated K-429 was associated with the Pacific Fleet.

Eight of these submarines now rest as underwater wrecks in the Northern Hemisphere, with five in the Atlantic Ocean and three in the Arctic Ocean. The ninth, K-429, was successfully raised and returned to active duty after both of its sinkings. The cause behind the sinking of USS Scorpion remains unknown.

Three of the submarines were lost with all crew members, comprising two from the United States Navy (resulting in the loss of 129 and 99 lives) and one from the Russian Navy (resulting in the loss of 118 lives). These incidents mark the three largest losses of life in submarine accidents. Except for K-27, which was deliberately scuttled in the Kara Sea due to the deemed costliness of proper decommissioning, all others sank as a result of unforeseen accidents. Notably, the Soviet submarine K-129 was carrying nuclear ballistic missiles when it tragically went down with all hands, but as it was a diesel-electric submarine, it is not included in this list.