How to Reverse an iPhone Update: Step-by-Step Guide

When an iOS update introduces unexpected bugs or drains your device’s performance, reverting to a previous version can feel like the only solution. While Apple does not provide a direct “undo” button in Settings, it is entirely possible to reverse an iPhone update by downgrading to an older, compatible version of iOS. This process involves forcing your device into Recovery Mode, using iTunes or Finder to put it into a firmware restore, and selecting the appropriate IPSW file. The key is that you must act quickly, as Apple typically closes the validation window once a new update is released, preventing devices from checking back to earlier software versions.

Understanding iOS Version Validation

Before diving into the steps, it is essential to grasp how Apple’s version signing process works. When you update your iPhone, the device contacts Apple’s servers to verify the build number against a list of accepted configurations. If the update is recent and has not been patched, the installation proceeds normally. However, once Apple stops signing a specific firmware version—usually within days of a new release—your device will no longer be able to revert to that build. This security measure ensures users stay current but creates a narrow timeframe for downgrading. Therefore, checking the status of a firmware’s signature before you begin is critical to avoid wasting time on an impossible task.

Preparing Your Device and Computer

A successful downgrade starts long before you plug in your phone. You must ensure that your computer has the latest version of iTunes (on Windows) or Finder (on macOS Catalina and later) installed. You also need a stable internet connection and, most importantly, a backup of your data. Since the downgrade will require a full restore, any unsaved progress could be lost. Back up your iPhone to iCloud or to your computer so that your messages, photos, and app data remain recoverable. Additionally, make sure your Mac or PC has enough storage space to hold the IPSW file, which can be several gigabytes in size.

How to Identify the Correct IPSW File

Finding the right firmware file is the technical cornerstone of reversing an update. Each IPSW file is specific to a device model, such as iPhone 12 or iPhone 15, and you cannot mix them up. To identify the correct file, locate your device’s model number, which can be found in Settings under General > About, or by checking the text on the back of the phone. Compare this number with a reputable database of IPSW files that lists versions still open for signing. Download the exact IPSW file that matches your hardware model and target iOS version. Using the wrong file will result in errors during the restore process and may brick your device.

Locating Your iPhone Model Number

• Open the Settings app on your device.
• Tap General, then tap About.
• Look for the entry labeled Model or Model Number.
• Note the number or text displayed to determine your exact hardware version.

Executing the Restore in Recovery Mode

With the correct IPSW file saved on your computer, you must put your iPhone into Recovery Mode to bypass the current software and load the old firmware. The method varies slightly depending on the model of your device. For most iPhones without a Home button, you quickly press and release the Volume Up button, then the Volume Down button, and finally hold the Side button until the Recovery Mode screen appears. For devices with a Home button, you hold the Side button and the Home button simultaneously until the screen goes black and the connect-to-iTunes icon shows. At this point, iTunes or Finder should detect your device in an error state and offer you the option to restore or update.

Loading the IPSW File and Completing the Downgrade

When your device appears in recovery mode, hold the Shift key (Windows) or Option key (Mac) while clicking the Restore iPhone button in iTunes or Finder. Navigate to the IPSW file you downloaded earlier and select it. Confirm the restore, and the software will begin to flash down to the older version. This process can take several minutes, during which you should avoid unplugging the device or interacting with the computer. Once the installation is complete, your iPhone will restart into the older version of iOS. At this stage, you can restore your data from the backup you created earlier, effectively returning your phone to a functional, pre-update state.