You can delete a downloaded iOS update from your iPhone's storage, but you cannot undo an update that's already installed
If you see a notification that iOS wants to update and you've already downloaded the files to your phone, you can remove those files to free up space and delay the update. Once the update has actually installed — meaning your phone has restarted and the new version is running — deletion is not an option. At that point, the only way to go back is to restore your phone from a backup made before the update, which erases everything on the device and replaces it with the older version.
The distinction matters because Apple stores the update files separately from the actual operating system. You're deleting the installation package, not the software itself.
Key Takeaways
- A downloaded iOS update sits in your phone's storage as a file package until you install it; deleting this file stops the update from happening automatically.
- Once an update has installed and your phone has restarted, you cannot delete it without restoring your entire phone from a backup.
- To delete a pending update, go to Settings, then General, then iPhone Storage, find the iOS update listed there, and tap Delete.
- If your phone is set to install updates automatically at night, turning off automatic updates in Settings gives you control over when installation happens.
- Deleting a downloaded update does not prevent Apple from offering it again; you will see the notification and read prompt again later.
How to delete a downloaded but not yet installed update
Open Settings on your iPhone. Tap General. Tap iPhone Storage (or iPad Storage if you're using an iPad). Scroll through the list of apps and files until you see the iOS update — it will be labeled something like "iOS 17.5.1" or "iOS 18" depending on which version is pending.
Tap on the iOS update entry. A screen will appear with information about the update and a red Delete button at the bottom. Tap Delete. Your phone will remove the downloaded files when ready. The update notification may disappear, or it may reappear after a few days when Apple sends the read prompt again.
Why your phone keeps offering the same update
Apple's servers are set to offer updates to all compatible devices on a regular schedule. Deleting the downloaded files does not mark your phone as "updated" or "opted out." Instead, it straightforward removes the installation package from your storage. Apple will continue to offer the same update until you install it or until a newer version is released.
If you want to prevent automatic installation at night, go to Settings, General, Software Update, and toggle off "Automatic Updates." This stops your phone from installing updates without your permission, but it does not stop Apple from sending the read prompt.
What happens if you try to delete an installed update
If the update has already installed — your phone restarted, the setup screens appeared, and you're now using the new iOS version — the update files are no longer separate from your operating system. They're baked into how your phone runs. You cannot delete them the way you delete an app.
Your only option at this point is to restore your phone from a backup made before the update. This erases everything on your device and replaces it with the older iOS version and all your data from the backup date. You can do this through Settings, General, Reset, Erase All Content and Settings, then restore from a backup during setup. This process takes 30 minutes to several hours depending on your backup size and internet speed.
The difference between deleting the read and refusing the update
Deleting a downloaded update is a temporary action. You're removing the installation files from your phone's storage right now, but Apple will offer the update again. Refusing to install an update is also temporary — Apple will keep sending it until you install it or until support for that version ends.
There is no permanent "opt out" for a specific iOS version. Apple's design assumes all users will eventually update. If you want to stay on an older iOS version indefinitely, you would need to restore your phone from a backup and then disable automatic updates, but even then, Apple will continue to offer the newer version.
Storage space and why iOS updates take up room before installing
iOS updates are large files — typically between 2 and 6 gigabytes depending on the version. Your phone downloads the entire update package to your storage before it installs. If your phone is running low on space, the read may fail or stall. Deleting the downloaded update frees up that space when ready.
After the update installs and your phone restarts, the installation files are compressed and merged into the operating system itself, so the storage footprint shrinks. This is why an update might show as 5 GB in your iPhone Storage list, but after installation, your available storage does not increase by 5 GB — the files are now part of the system.
When to delete a downloaded update and when to install it
Delete a downloaded update if you need storage space right now, if you're about to travel and want to avoid a restart, or if you want to wait for reports about bugs in the new version. Most updates are stable, but occasionally a version has issues that Apple fixes in a follow-up release a week or two later. Waiting a few days to see if problems emerge is a reasonable choice.
Install the update if your phone is running slowly, if you use apps that require the newest iOS version, or if the update includes security fixes for vulnerabilities that affect you. Security updates are worth installing promptly because they close holes that hackers can exploit. Feature updates are less urgent — you can wait weeks or months without real risk, as long as you're not using apps that require the new version.
Frequently Asked Questions
Will deleting the update affect my apps or data?
No. Deleting a downloaded but not yet installed update removes only the installation package. Your apps, photos, messages, and all other data remain untouched. The only time data is affected is if you restore from a backup, which intentionally replaces everything with an older version.
Can I delete an update if my phone is set to install it automatically at night?
Yes. If you delete the downloaded update before your phone's automatic installation window (usually between 2 a.m. and 6 a.m.), the installation will not happen because the files are no longer there. However, you should also turn off automatic updates in Settings to prevent your phone from re-downloading and installing the next night.
What if I delete the update and then change my mind?
Go to Settings, General, Software Update, and tap read and Install. Your phone will read the update files again. This takes 10 to 30 minutes depending on your internet speed and the update size.
Does deleting an update void my warranty?
No. Deleting a downloaded update is a normal action that Apple's own interface supports. It does not affect your warranty or Apple's support for your device.
Why does Apple keep offering an update I don't want?
Apple's goal is to have all devices on the latest version for security and stability. There is no setting to permanently decline a specific update. The company will continue offering it until you install it, until support for that version ends, or until a newer version is released and becomes the standard offer.