How to backup iPhone before installing iOS 27

Upgrading your phone system is an important step. Below is how to safely back up data to prevent unexpected incidents.

Perhaps you are familiar with using iCloud Backup to maintain regular data backups. This feature works behind the scenes and provides maximum convenience, as long as you have enough storage space in iCloud. Come in Settings > iCloud > iCloud Backup (iCloud Backup) and enable the option Back Up This iPhone (Back Up This iPhone) if it is not enabled.

However, when switching to an official iOS version (for example, from iOS 26 to iOS 27), using iCloud Backup creates a problem: You can’t restore data from that cloud backup if you want to go back to an earlier version of the operating system. Unfortunately, iCloud only keeps the most recent backup; you cannot arbitrarily choose from previous backups. If you try to use an iOS 27 cloud backup to restore to iOS 26, you’ll get an error.

That’s why you need to back up data to your computer before running iOS 27.

Should local backups be encrypted?

Before creating an archived backup, you need to consider whether you want to enable the option “Encrypt local backup” (Encrypt local backup) or not. For security reasons, this feature scrambles data to prevent others from accessing your information even if they have access to your computer. This option also helps protect sensitive information in backups, such as saved passwords and personal data from the Health and Fitness apps.

The inconvenience is that you will need to create a separate password for this backup. If you forget or lose that password, the entire backup will become useless. Therefore, you should write down your password in a place where you can easily find it when needed.

Create a local iPhone archive on your Mac

Creating this type of backup only requires a sync cable, hard drive space, and a little patience. If using newer iPhone models, use a USB-C cable that supports high-speed data transfer; The cable that comes with the iPhone is usually only used for charging and has a much slower speed. The steps are as follows:

1. Connect your iPhone to your Mac.
2. Open a new Finder window (select File > New Finder Window or press Command-N).
3. In the left sidebar, select your iPhone in the section Locations (Location).
4. If you want to encrypt data, check the box “Encrypt local backup” and set a password.
5. In the card Generalclick the button Back Up Now.
6. When the backup is complete, click Manage Backups (Backup management).
7. Right-click on the backup you just created and select Archive.

Screenshot of a Finder window on macOS showing a connected iPhone. Phone name and button Back Up Now highlighted with red callout frames.

Taking the extra step of marking a backup as “Archive” helps protect it from being overwritten by the next local backup or from being automatically deleted if your Mac is running out of space.

Create a local iPhone archive on Windows

The iTunes application is still the main tool for managing iPhone when connected to a Windows computer. Open iTunes and do the following:

1. Connect your iPhone to your Windows computer.
2. Open the Apple Devices app and click the iPhone button in the upper left corner.
3. Click General.
4. If you want to encrypt your data, select the option Encrypt local backup and set a password.
5. Click Back Up Now.
6. Click Manage Backups.
7. Right click on the newly created backup and select Archive. This step helps protect the backup from being overwritten by a subsequent local backup or from being automatically deleted if the computer is running out of space.

Once you have your backup, you can start using iOS 27 with the confidence that if you need to go back to iOS 26, you can quickly restore your iPhone to normal operation.