Baldur’s Gate 3 makes the folder boundary important: each save folder contains the .lsv archive and related slot context. Backing up the whole folder avoids separating the main payload from supporting files. Campaigns can also be sensitive to mods, so SaveEditor.com treats mod compatibility as part of restoration rather than calling every failed load corruption. Larian cross-save is useful for recent saves, but a complete local archive is still the better long-term backup.
For this PC reference, the documented storage is Windows: %LOCALAPPDATA%Larian StudiosBaldur's Gate 3PlayerProfilesPublicSavegamesStory | macOS: $HOME/Documents/Larian Studios/Baldur's Gate 3/PlayerProfiles/Public/Savegames/Story/ | Linux / Steam Play: $XDG_DATA_HOME/Larian Studios/Baldur's Gate 3/PlayerProfiles/Public/Savegames/Story/. The known file or folder pattern is <save-folder><save-name>.lsv. Each campaign save is stored in its own folder and includes an .lsv archive. Preserve the whole save folder rather than extracting only the archive when making a normal backup.
Backup guidance: Copy the entire Story directory or selected complete save folders. For heavily modded campaigns, also keep the mod configuration required by that campaign. Steam Cloud is documented. Larian account cross-save can synchronize a limited set of recent saves across supported PC storefronts/platforms. Launcher and cloud context matters because The same Larian profile hierarchy is used across desktop platforms, with OS-specific base directories. Steam also exposes a remote cloud area.
Compatibility and recovery should stay conservative. An .lsv can be structurally valid but still depend on mods or game versions that are not present on the destination system. If the expected progress is not visible, When a campaign save fails after migration, check the exact save folder, mods, and profile before assuming the archive is damaged. Cloud cross-save only covers supported recent saves, not every local backup. SaveEditor.com only labels a game-specific editor as available when a separate linked Tool has a verified operational runtime; this reference page by itself is not an editor claim.