➡️ This is not to be confused with installing the actual Sims 4 game on an external drive. The game installation location is determined in EA App and there is no need to use a symlink for this.

As internal storage gets smaller we're forced to use cloud based solutions to store files and folders or resort to a trusty external drive. Cloud based only storage is not an option for the Sims 4 folder that contains all your saves, Mods, Library items and other user data because the game only looks in one place for your data:

Macintosh HD > Users > [your user account] > Documents > Electronic Arts > The Sims 4

If there is no Sims 4 folder in that location the game will create a new one. There is no way around this default Sims 4 folder location unfortunately, it is hard coded into the game. Because of this the only option to store the Sims 4 folder on an external drive is to create a symbolic link, otherwise known as a symlink.

Creating the symlink is relatively easy provided you understand the concept of what a symlink is and why you are creating it. You should also be familiar with Terminal on your Mac and the security and permission systems in place in whichever version of macOS you are running as these dictate the ability for the game to access the external drive and whether your Mac user account has permission to grant the necessary access.

You should also make sure you are using a good quality, fast external drive. You get what you pay for and if you bought a cheap drive, with low quality cables, you will most likely struggle to get the symlink to work because it will be too slow. For help buying an external drive and what to look out for read this guide.

I am not going to write step by step instructions here, the post will be far too long. Instead, you can read the detailed and comprehensive guide I wrote several years ago here https://bluebellflora.com/saving-your-sims-4-folder-to-an-external-drive/

If your symlink is not working it is down to user error. It really is that simple. macOS is a Unix based operating system and as such uses Unix commands which are all provided in the above linked guide.

This thread is for consolidating all posts related to the Mac symlink process here at Answers HQ. If you're a Windows user read Crinrict's excellent guide here https://crinrict.com/blog/2020/02/moving-windows-documents-folder-to-external-drive-via-symbolic-link.html. What I have provided below are a few of the common issues people face as a result of not entering the commands correctly or having the correct permissions in place.

Common issues reported and the solution:

Always check your external drive has the correct name in Disk Utility:

open Disk Utility (Applications > Utilities)
change View to Show All Devices then click on the drive in the left sidebar
the Mount Point shows the name of your drive. If there is a number added to the drive name it means the drive has not been properly ejected multiple times
Close Disk Utility and eject the drive
In Finder click on Go in the menu bar then Go To Folder. Enter /Volumes in the input field and hit return
in the /Volumes location, trash the folder(s) that has the same name as the external drive
Close Finder, plug the drive back in, open Disk Utility again to check the drive name in the Mount Point. If it matches try to create the symlink

In addition to checking the external drive mount point above, the following may also be helpful:

Terminal states my access/permission is denied

check your Mac user account is an Administrator account and not a Standard account.
check that Terminal has access to external drives, also known as Removable Volumes, and your Documents folder.

I'm constantly getting "Unable to start... Cannot start because the below file appears to be corrupted" error message

make sure the external drive is correctly formatted as either APFS or Mac OS Extended (Journaled). If it isn't, reverse the symlink, reformat the drive in Disk Utility and start again.
check your Mods actually aren't corrupted by downloading a compatible version from the creator.

I keep getting the error message "Unable to start... The Sims 4 is already running"

make sure the external drive is correctly plugged in and mounted.
check EA App has access to the external drive in System Settings > Privacy & Security. Give it Full Disk Access if necessary.
disable iCloud Drive
if the symlink folder in Documents is a white page instead of a folder with the little arrow the symlink has broken. Trash it and attempt to recreate the symlink.
Check the Mount Point in Disk Utility shows your exact external drive name and doesn’t have a number added to the drive name. If it does this means your drive has not been properly ejected multiple times. To fix it:
- eject the drive
- in Finder click on Go in the menu bar then Go To Folder
- enter /Volumes in the text field and hit Enter/Return
- in the Finder window that appears you should see a folder, not a drive icon, with the same name as your external drive. Trash it.
- plug the drive back in, check the mount point in Disk Utility is the exact drive name with no appended numbers, then try to create the symlink again.
- if the mount point is still showing a number you have problems with your drive. Consider reformatting it, trying different connector cables, or getting a better drive.

Terminal tells me No such file or directory

did you copy and paste the command from the guide and correctly substitute the name of your external drive? If you didn't copy and paste you may have used the wrong letters in the command. Copy and paste from the guide.
Does the folder you are trying to move or create a symlink to exist in the location you are stipulating in the command?

Terminal tells me Directory not empty in Step 1

Is there already a folder on the external with the same name as the folder you're moving? i.e. have you already copied over the Electronic Arts folder? If there is already a folder with the same name as the folder you're moving, Terminal will return this result.

Terminal tells me File already exists in Step 2 of the guide

Did you correctly complete step 1 or is there still an Electronic Arts or Sims 4 folder in your Documents folder? If the folder is still there you have not correctly moved it in Step 1.

If you have iCloud Drive enabled to store your Documents folder in the cloud and Optimise Storage enabled, it will cause issues with the symlink. I strongly advise to disable this iCloud feature otherwise you will have issues, especially if you use Mods. As a reminder, creating this symlink is aimed at people storing their Electronic Arts/Sims 4 folder locally. Using iCloud Drive stores your folder in the cloud and locally. For help with iCloud see this thread https://answers.ea.com/t5/Technical-Issues-Mac/READ-FIRST-Saves-CC-Mods-or-Library-items-disappeared/m-p/10242133