Nine nuclear submarines have sunk, either by accident or by scuttling.
These are amongst the largest losses of life in a submarine (along with the non-nuclear USS Argonaut with 102 lives lost and Surcouf with 130 lives lost).
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.
Of the nine sinkings, two were caused by fires, two by weapon explosions, two by flooding, one by bad weather, and one by scuttling due to a damaged nuclear reactor.
The ninth submarine, K-429, was raised and returned to active duty after both of her sinkings.