Fallout 4’s location is straightforward, but modded restoration is not. A base .fos file can reference content from plugins, and F4SE can add a paired cosave. The safest archive therefore includes the full save directory plus enough information to rebuild the mod environment. A failed load after moving PCs is not automatically evidence of file corruption; missing plugins, changed load order, or an absent cosave can be the real cause.
Where Fallout 4 stores PC saves
The researched save-location boundary is Windows: %USERPROFILE%DocumentsMy GamesFallout4Saves | Linux / Steam Play: Steam Play: <SteamLibrary-folder>/steamapps/compatdata/377160/pfx/. The known file or folder pattern is *.fos
*.f4se (when created by F4SE). This is the practical starting point because launcher, profile, and storefront context can change which copy is active even when two folders look similar.
Storefront and profile differences
Documented launchers or storefronts: Steam, Microsoft Store / Xbox app. The standard Documents path is the primary Windows reference. Microsoft Store packaging can differ, so locate the active edition before restoring a file. When looking for a missing save, identify the executable/storefront you actually launched and the user/profile that created the progress before copying anything between directories.
Cloud synchronization
Cloud behavior depends on storefront. OneDrive may also synchronize the Documents tree if Windows folder backup is enabled. A cloud service should be treated as another copy of the save, not as proof that the local folder is disposable. Before a manual restore, let synchronization finish, make an offline backup, and avoid starting the game while files are being replaced.
What the files represent
Base Fallout 4 saves use .fos. F4SE-enabled installations can create companion .f4se cosaves; preserving only one side of a modded save may remove script-extender state. The current filename/folder evidence is *.fos
*.f4se (when created by F4SE). File-extension context: .fos, .f4se A location guide does not claim that every file in the directory is safe to edit or that files from another storefront are automatically interchangeable.
If the save is not where expected
If an apparently valid save crashes on load after migration, verify missing plugins and script-extender dependencies before replacing more files. Also check whether Documents is redirected by OneDrive. Also check redirected Documents folders, Steam Play prefixes, account IDs, and launcher-specific containers where applicable. Preserve every candidate copy before testing a restore so troubleshooting does not destroy the only surviving version.
Verification context: The standard Windows and Steam Play save locations were reviewed against current PCGamingWiki coverage. Format notes distinguish base .fos saves from optional F4SE cosaves.