How do I downgrade my iPhone from iOS 26 to iOS 18.5?

Ios 26 update downgrade to ios 18.5 ios 26 is not satisfactory

[Re-Titled by Moderator]

Original Title: ios 26 downgrade to 18.5

Posted on Jun 18, 2025 10:47 PM

Top-ranking reply

linobrendler

Level 1

14 points

Posted on Oct 14, 2025 2:12 PM

Unfortunately, you can’t downgrade an iPhone to iOS 18.5 once it’s been updated to iOS 26.

Apple only allows installing versions of iOS that are still being signed — and older versions like iOS 18.5 are no longer signed by Apple’s servers. That means even if you have an IPSW file, the installation will fail because the signature check won’t pass.

If iOS 26 feels unsatisfactory, the best thing you can do is:

Submit feedback to Apple here: https://apple.com/feedback/ – this helps improve future releases.
Check for upcoming updates under Settings › General › Software Update – Apple often fixes issues quickly with minor updates.
Restore your iPhone via Finder or iTunes if you think something went wrong during the update. This can sometimes improve performance.

Once Apple stops signing iOS 26 and releases a new version (like iOS 26.1), you can only move forward, not back.

If you just want your phone to feel faster or more stable again, a clean restore from backup usually helps a lot!

View in context

Similar questions

168 replies

Jan 9, 2026 8:20 PM in response to eddikit

eddikit wrote:

Hey lobsterghost1, I’m back to inform the masses that it was in fact apple inc. With the update of iOS 26 being released. The issue has resolved, I thank you deeply for “helping me” with my issue. I wish you nothing but the best in life and have a lovely 2026! 🥂

I'm very happy to see I was able to help you and wish the same for you in 2026 and beyond!