# How to Install Mods on Sims 3

Source: https://sims3mods.com/how-to-install

Last updated: 2026-11-10

To install mods on Sims 3, create `Documents\Electronic Arts\The Sims 3\Mods\Packages`, put a **Resource.cfg** file in `Mods`, and copy unzipped `.package` files into `Packages`. A `.sims3pack` file is different: double-click it and install it through the game launcher. Delete the four cache files, then start the game.

## First check the file type

Sims 3 downloads come in two formats, and each one installs a different way.

| File | What it usually is | Where it goes | How to remove it |
| --- | --- | --- | --- |
| `.package` | Script mods such as NRaas, tuning mods, default replacements, most CC | `Documents\Electronic Arts\The Sims 3\Mods\Packages` | Delete the file |
| `.sims3pack` | Clothes, objects, lots, Sims and worlds made for the launcher | `Documents\Electronic Arts\The Sims 3\Downloads`, then installed by the launcher | Uninstall it in the launcher's Installed Content tab |
| `.zip`, `.rar`, `.7z` | An archive that holds one of the two above | Nowhere. Extract it first | |

The game cannot read archives. If a mod still does nothing after you copied it in, check that you copied the file from inside the archive and not the archive itself.

## Install a .package mod

- Close the game and the launcher.

- Open `Documents\Electronic Arts\The Sims 3`. This is the folder with your `Saves`, not the install folder in Program Files.

- If there is no `Mods` folder yet, set it up once: a `Mods` folder holding a `Packages` folder, an `Overrides` folder and a `Resource.cfg` file. The [Mods folder page](/mods-folder) has the exact file contents and two ready-made downloads.

- Extract the download and copy only the `.package` file into `Mods\Packages`. Subfolders such as `Packages\NRaas` are fine.

- Delete the cache files listed below.

- Start the game. NRaas says a pop-up lists the script mods it loaded. Tuning mods, sliders, skins, clothes and objects never appear in that list, so check those in the game itself.

Use `Overrides` only when a creator tells you to. NRaas's install page says every other `.package` belongs in `Packages`. Never keep two copies of the same mod: NRaas warns the result is unpredictable.

## Install a .sims3pack file

- Double-click the `.sims3pack` file. The launcher opens and installs it. You can also copy the file into `Documents\Electronic Arts\The Sims 3\Downloads` and install it from the launcher's Downloads tab.

- Check the launcher's **Installed Content** tab. If **Run without custom content** is ticked there, untick it, or nothing you installed will load.

- Start the game.

Launcher content is stored in the `DCCache` folder, so do not empty that folder when you clean caches. To look inside a `.sims3pack` before installing it, [CUSTARD](https://modthesims.info/d/390235) on Mod The Sims opens the file and flags corrupted items. Script mods are never `.sims3pack` files.

## Delete the caches every time

With the game closed, delete these files in `Documents\Electronic Arts\The Sims 3`. EA Help says they are safe to remove and the game makes them again.

- `CASPartCache.package`
- `compositorCache.package`
- `scriptCache.package`
- `simCompositorCache.package`
- `socialCache.package`, if you have Showtime (NRaas lists this one)

If something still looks wrong, EA Help's next step is to delete the files inside `Thumbnails`, then the files inside `WorldCaches`.

## EA app, Steam and Mac

| Version | What changes |
| --- | --- |
| EA app (Windows) | Nothing in the steps above. The Mods folder is in Documents for every Windows version |
| Steam | Same Mods folder. Only engine patches differ: files such as `Sims3SettingsSetter.asi` go in `Steam\steamapps\common\The Sims 3\Game\Bin` |
| Mac | Same layout in `/Users//Documents/Electronic Arts/The Sims 3/Mods`. From macOS 10.15, EA says only the 64-bit version runs, and it installs as a separate game in the EA app |

Script mods are built for a game patch. NRaas labels each download with the patches it supports (1.67, 1.69 and 1.70 on its mod list), and other creators publish separate files per patch. Check your patch number before you download. EA suggests players on 1.67 or earlier update to 1.69. The [NRaas page](/nraas) shows which mods to start with.

## Mods not showing up? Check these

| Symptom | Likely cause and fix |
| --- | --- |
| No mod loads at all | `Resource.cfg` is missing, sits in the wrong folder, or is really named `Resource.cfg.txt`. It must be directly in `Mods` |
| One mod is missing | The file is in `Mods` and not `Mods\Packages`, it is still zipped, or it was made for another patch |
| NRaas menu options are missing | NRaas says this is nearly always a bad install: an outdated script mod, a duplicate, or an old Mods folder left inside the game's install directory |
| Launcher content is missing | Untick **Run without custom content** in the launcher |
| Game crashes while loading | EA Help: run without custom content once. If the game loads, add your content back a little at a time to find the bad item |
| Launcher says the version is incompatible | Delete `Version.tag` in `Documents\Electronic Arts\The Sims 3` |

The [main Sims 3 mods page](/) has a symptom picker for crashes, lag and Error 12.

## FAQ

### Where do I put mods in Sims 3?

`.package` files go in `Documents\Electronic Arts\The Sims 3\Mods\Packages`. `.sims3pack` files are installed through the launcher, which reads them from the `Downloads` folder in the same place.

### Do I have to turn mods on in the game options?

No. The setup guides from Mod The Sims and NRaas need no in-game setting: a correct Mods folder with Resource.cfg is enough. The one switch to check is Run without custom content in the launcher, which must stay unticked.

### Can I install Sims 3 mods on a Mac?

Yes. The folder layout is the same under Documents/Electronic Arts/The Sims 3. The engine patches named on this site are Windows files.

### Do Sims 4 mods work in The Sims 3?

No. Sims 2 and Sims 4 also use .package files, but the game cannot use them, and a wrong-game file in your Mods folder can cause trouble. Remove them.