Board Thread:General Discussion/@comment-195.215.27.13-20160430013712/@comment-27918149-20181217211426

It's also available on EpicGames.

%USERPROFILE%\AppData\LocalLow\Unknown Worlds\Subnautica\Subnautica\SavedGames

https://www.reddit.com/r/subnautica/comments/a6qoky/need_help_with_epic_games_save_file_location/

https://pcgamingwiki.com/wiki/Subnautica#Save_game_data_location