How to Clean Your Mac Before Selling It (Without a Full Reset)

If you are getting ready to hand your Mac to a new owner, you have two options: erase everything and reinstall macOS from scratch, or do a thorough deep clean that removes your personal data without touching the OS. Knowing how to clean your Mac before selling it — and when each approach is the right call — can save you an hour of reinstallation time while still leaving no trace of your files, accounts, or browsing history.

Factory Reset vs. Deep Clean: Which One Do You Need?

A full erase-and-reinstall (what Apple calls "Erase All Content and Settings") wipes the entire drive and puts macOS back to day one. It is the gold standard for privacy, but it is not always necessary.

If you choose a deep clean, you need to be systematic. Miss one step and your Apple ID, saved passwords, or personal files can end up in someone else's hands. The checklist below covers every step in the right order.

Step 1: Back Up Everything First

Before you delete a single file, create a current backup. Use Time Machine to an external drive, or copy critical files to iCloud Drive or another cloud service. The cleanup steps below are permanent — there is no undo once files leave the Trash.

1. Connect an external drive and open System Settings > General > Time Machine.
2. Select your drive as the backup destination and let the backup complete.
3. Verify the backup by clicking Browse Backup Disk and spot-checking a few folders.

Step 2: Sign Out of All Apple Services

This is the most important privacy step. Your Apple ID ties your device to iCloud, iMessage, the App Store, and FaceTime. Sign out before anything else.

1. Open System Settings > [your name] (Apple ID).
2. Scroll to the bottom and click Sign Out. Enter your password when prompted.
3. macOS asks whether to keep a copy of iCloud data on this Mac — choose Keep a Copy so it stays on the drive you are about to clean (it will be deleted in a later step), or choose Delete from Mac to remove it immediately.
4. Open Messages and go to Messages > Settings > iMessage. Click Sign Out.
5. Open FaceTime > Settings > General and click Sign Out.

If you use iCloud Keychain, signing out of your Apple ID deactivates it on this device — your passwords remain safe in iCloud on your other devices.

Step 3: Deauthorize and Disconnect Third-Party Accounts

1. iTunes / Music store authorization: Open Music (or TV) > Account > Authorizations > Deauthorize This Computer. Each Apple ID can authorize up to five computers; deauthorizing frees the slot.
2. Browsers: In Safari, open Safari > Settings > General, uncheck Safari is used as default browser, then go to Privacy > Manage Website Data and click Remove All. In Chrome or Firefox, sign out of your account within each browser, then clear all browsing data including saved passwords and cookies.
3. Cloud services: Sign out of Dropbox, Google Drive, OneDrive, or any other sync client from each app's preferences.
4. Internet Accounts: Open System Settings > Internet Accounts. Remove every account listed there (Google, Exchange, LinkedIn, and so on) by selecting each one and clicking the minus button.

Step 4: Remove Your Personal Files and Documents

1. Open Finder, navigate to your home folder (Go > Home), and delete the contents of Documents, Downloads, Desktop, Movies, Music, and Pictures. Move everything to an external drive first if you haven't already.
2. Delete your browser profiles. For Chrome: ~/Library/Application Support/Google/Chrome/. For Firefox: ~/Library/Application Support/Firefox/Profiles/.
3. Empty the Trash when done: right-click the Trash icon and choose Empty Trash.

Step 5: Uninstall Your Personal Apps and Their Leftover Files

Simply dragging an app to the Trash removes the app bundle but leaves behind preference files, caches, application support data, and sometimes background services. On a Mac you are selling, those leftovers can contain login tokens, license keys, and personal settings.

The locations to check for each app are:

• ~/Library/Application Support/AppName/
• ~/Library/Preferences/com.developer.appname.plist
• ~/Library/Caches/com.developer.appname/
• ~/Library/Logs/AppName/
• ~/Library/Containers/com.developer.appname/ (sandboxed App Store apps)
• /Library/LaunchDaemons/ and /Library/LaunchAgents/ (background services)

To find all files associated with an app from Terminal, note the bundle ID first:

mdls -name kMDItemCFBundleIdentifier /Applications/AppName.app

Then search your Library:

find ~/Library -iname "*com.developer.appname*" 2>/dev/null

And check system-level folders (requires your admin password):

sudo find /Library -iname "*com.developer.appname*" 2>/dev/null

Doing this for every app you have installed is tedious. Crumb's Uninstaller tab lists your apps alongside all their associated Library files in a single view — you select an app, review the leftover files grouped by type, and remove both the app and its traces in one pass. It also handles system-level LaunchDaemons that a home-folder search would miss entirely.

Step 6: Clear Caches, Logs, and Temporary Files

Even after removing apps, cache folders accumulate data from regular use. These are safe to delete — macOS and apps rebuild them as needed.

1. Open Finder, press CmdShiftG, type ~/Library/Caches and press Return.
2. Select all folders inside and move them to Trash. (Note: do not delete the ~/Library/Caches folder itself, only its contents.)
3. Navigate to ~/Library/Logs and delete the contents.
4. Navigate to ~/Library/Saved Application State and delete the contents.
5. In Terminal, you can also clear the system-level user cache with:

sudo rm -rf /Library/Caches/*

Be careful with the system cache path — always double-check you typed it correctly before pressing Return. Cleaning is permanent.

Step 7: Remove Additional User Accounts

If the Mac has multiple user accounts (family members, work accounts), they all need to be removed. Each account's home folder is a separate island of personal data.

1. Open System Settings > Users & Groups.
2. Select each non-admin account and click the minus button to delete it. Choose Delete the home folder when prompted — this permanently removes all files in that user's /Users/username/ directory.
3. Repeat for every account except the one you are currently signed into.

If you use Crumb with the cross-user cleaning option enabled, it can scan all user Library folders for leftover app data in a single pass rather than requiring you to log into each account separately.

Step 8: Reset System Preferences

A few system settings hold personal information worth clearing:

• Bluetooth devices: Open System Settings > Bluetooth, hover over each paired device, click the info button, and choose Forget This Device.
• Network preferences: Open System Settings > Wi-Fi, click the details button next to saved networks you want to remove, and delete the ones you don't want the next owner to see.
• Location Services: Open System Settings > Privacy & Security > Location Services and review which apps have access. Removing the apps (Step 5) takes care of most of these automatically.
• Keychain: Your Keychain holds saved passwords and certificates. Signing out of your Apple ID deactivated iCloud Keychain. To clear the local Keychain as well, open Keychain Access (in /Applications/Utilities/), select the login keychain, and delete any personal entries.

Step 9: Secure Empty the Trash and Verify

1. Empty the Trash one final time.
2. Restart the Mac to flush any remaining session data from memory.
3. Open System Settings > General > About and confirm your Apple ID is no longer shown.
4. Open Safari and verify there is no browsing history or saved passwords under Safari > History and Settings > Passwords.

When to Do a Full Erase-and-Reinstall Instead

The steps above cover most use cases, but a deep clean is not equivalent to a true factory reset. If you are selling to someone you do not know, or if the Mac contains particularly sensitive data (health records, financial documents, work credentials), the safer path is a full erase.

On Macs with Apple Silicon or a T2 chip (most Macs from 2018 onward), go to System Settings > General > Transfer or Reset > Erase All Content and Settings. This single command signs out of all Apple services, erases the APFS volume, and reinstalls a clean macOS — all in about 30 minutes. On older Intel Macs without a T2 chip, you will need to boot into macOS Recovery (CmdR on startup) and use Disk Utility to erase the drive before reinstalling.

Conclusion

A deep clean is a perfectly reasonable option when you need the next user to keep the existing macOS installation or when a full reinstall is impractical. The key is being systematic: sign out of Apple services first, then remove apps along with their Library leftovers, clear caches and logs, delete additional user accounts, and do a final verification pass. Tools like download Crumb make the app-plus-leftovers step significantly faster, especially if you have accumulated a long list of installed apps over the years. Whether you do it manually or with help, the result is a Mac that is genuinely clean — ready for its next owner with none of your data attached.