The Sims 4 already keeps several recovery generations next to each main slot, which makes indiscriminate cleanup a mistake. A good backup preserves the whole saves directory, including `.save.ver0` through `.ver4` files. If a slot becomes unusable, duplicate the directory first and test recovery on the copy. Also remember that the Documents tree may be redirected or synchronized by OneDrive, so the file you replace locally may not be the only copy involved.
Prepare the source PC
On the source system, identify the actual The Sims 4 save root: Windows: %USERPROFILE%DocumentsElectronic ArtsThe Sims 4saves | macOS: $HOME/Documents/Electronic Arts/The Sims 4/saves/ | Linux / Steam Play: Steam Play: <SteamLibrary-folder>/steamapps/compatdata/1222670/pfx/. The expected file/folder pattern is Slot_*.save
Slot_*.save.ver0 … .ver4. Close the game, let the active launcher finish writing and synchronizing, then make a complete offline copy rather than transferring a file that may still be open.
Preserve storefront and profile identity
Documented storefronts: EA app, Steam, Epic Games Launcher. The active Windows saves still live under Documents/Electronic Arts. Steam and Epic launch through EA services but should not be assumed to maintain a separate independent save directory. A transfer between two PCs is simplest when both systems use the same storefront/account/profile context. If the destination uses a different store or container, treat that as a migration problem rather than an ordinary restore.
Move the complete save boundary
Copy the complete saves directory so each main slot and its .ver0-.ver4 recovery generations remain together. Put the copied data on the destination only after confirming the destination save path. If the game creates a new empty save first, keep that new folder as another backup so you can compare structures and revert.
Handle cloud sync deliberately
OneDrive Documents backup can synchronize or redirect the saves directory when enabled. Treat that as a second copy source when diagnosing unexpected restores. Decide whether the local transferred copy or cloud copy should be authoritative before launching the game. If possible, preserve both. After the transferred save loads correctly, make a fresh in-game save and let the launcher synchronize normally.
Check compatibility before blaming the transfer
The game maintains main Slot_*.save files and several rotating .save.verN recovery copies. These historical versions are valuable rollback points and should be preserved before manual recovery. Compatibility note: The save can depend on installed packs, custom content, and mods. Missing content after migration is not the same as binary save corruption. If the destination does not see the transferred progress, If a main Slot file fails, preserve it first, then work from a copied .save.verN generation. Do not rename over every version until one recovery copy has been tested. Verify game edition/version, store, profile IDs, redirected folders, and mod/DLC dependencies before editing the save itself.
Verification context: Windows/macOS/Steam Play save paths and storefront/OneDrive context were reviewed against current PCGamingWiki coverage. Rotating Slot recovery filenames follow the standard Sims 4 desktop layout.