How to Reinstall macOS (Sequoia/Sonoma) with Recovery Mode/USB

If your Mac system keeps crashing, runs slow, or has other severe problems, you may want to reinstall your Mac OS to set up a new Mac. Check the 2 ways below for how to reinstall macOS (Sequoia, Sonoma, Ventura, Monterey, etc.) without losing data.

Way 1. How to Reinstall Mac OS (Sequoia/Sonoma) with Recovery Mode

Step 1. Back Up All Need Data on Your Mac

If you also want to wipe your Mac before reinstalling the Mac OS, you should make a backup of all important files on your Mac. In case something goes wrong, it’s also highly advised you back up your Mac first to reinstall macOS without losing data.

You can copy and paste needed files to an external USB or hard drive. You can also sync all needed data to a cloud service like your iCloud account. Still, you can also use the Time Machine feature in Mac to back up Mac data to an external storage device.

Step 2. Press Command + R to Enter Recovery Mode

On an Intel-based Mac, you can start or restart your Mac computer, and immediately press and hold the Command + R keyboard shortcut. This will let you reinstall your current version of macOS after booting to Mac Recovery Mode.

On an Apple Silicon Mac, you can press and hold the Power button. When you get to the startup options screen, you can select Options and click Continue to access the Mac recovery options.

Step 3. (Optional) Wipe Disk before Reinstalling Mac OS

If you want to do a clean install of your Mac system, you can wipe the Mac hard disk first before you reinstall OS on your Mac.

1. After you get into Recovery Mode on your Mac, you can select Disk Utility and click Continue.
2. In the Disk Utility window, you can select your Mac’s system drive and click the Erase button.
3. Choose a name, format, and scheme for the hard drive. Click the Erase button to start erasing your Mac.
4. Close Disk Utility after the disk is erased. You will be taken back to the macOS Utilities window.

Step 4. Start to Reinstall macOS (Sequoia/Sonoma)

On the Recovery Mode screen, you can select Reinstall macOS Sonoma or Reinstall macOS Ventura and click Continue. If your Mac’s current OS is Monterey, Big Sur, or another older macOS version, it will show the corresponding current OS you can install.

Select Macintosh HD when you are asked which disk you want to install macOS. Follow the on-screen instructions to install a new copy of macOS Sequoia, Sonoma, Ventura, Monterey, or Big Sur, onto your Mac.

Reinstalling macOS with the Mac Recovery system will not remove your personal data. If you intend to sell your Mac and want to erase all data on it, you should follow the operation in Step 3 to wipe all data first.

Step 5. (Optional) Restore Data from Backups

To reinstall macOS without losing data, you can restore data from the backups you made in Step 1.

To restore data from a Time Machine backup, you can click Apple > System Settings > General > Time Machine, and follow the instructions to restore data and files to your Mac. Alternatively, you can also launch the Time Machine utility from Mac Recovery Mode.

Related: System Restore Mac: Restore Mac to a Previous Date in 3 Ways

Way 2. How to Reinstall macOS (Sequoia/Sonoma) from USB Drive

In general, you can follow Way 1 to reinstall macOS and don’t need a Mac bootable installer. But if you have a bootable installer for macOS, you can also reinstall your Mac OS from the bootable installer.

Step 1. Boot Your Mac from the Bootable USB

For Intel-based Macs:

1. Plug the USB installation drive into an open USB port on your Mac, you may use a USB adapter on your MacBook (Pro/Air).
2. Start or restart your Mac, and immediately press and hold the Option key.
3. Select the bootable installer volume and press Enter to boot your Mac from the USB drive.

For Apple M1/M2 Macs:

1. Connect the USB drive to your Mac computer.
2. Press and hold the Power button to start your Mac.
3. Then you should see an option to select the bootable USB drive as the startup disk. Select the USB to boot your Mac.

Step 2. Reinstall macOS (Sequoia/Sonoma) from USB

After you get to the macOS installer screen, you can follow the on-screen instructions to complete the macOS reinstallation process.

Conclusion

In conclusion, this post introduces 2 ways to help you reinstall your Mac OS. Step-by-step guides are included. Hope it helps.

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