How can I downgrade from ios 26 to 18.5 even if I lose the data

You cannot downgrade iOS versions to specific numbers like 18.5 on an iPhone. If battery health is a concern, you can try recalibrating the battery or seeking help from an Apple Store.

Haudeda wrote:

You cannot downgrade iOS versions to specific numbers like 18.5 on an iPhone. If battery health is a concern, you can try recalibrating the battery or seeking help from an Apple Store.

What???

• Downgrading from the iOS beta 26 version to the last stable iOS 18 version is recommended. I suspect the OP was not aware that iOS 18.6 was just released today and it is now the latest release instead of 18.5.
• Battery calibration is done automatically by the system when allowed to charge to 100%. That is done for adjustments in reported values seen in Settings. I hope you are not suggesting that the user drains and recharges the battery like you used to do with Ni-Cd batteries for calibration. That will actually damage a Li-Ion Battery and certainly not recommended.
• The Apple Store will not help when a user has beta software installed. That is not the correct answer, the user must remove the beta before any support is available to them. That information is clearly available in the FAQ's for beta use.

Maybe you should try reading the information provided when you joined the beta program...

There is no evidence to suggest that your Battery Heath / Maximum Capacity is going to improve if you revert to iOS 18.6.

When was the last time that you replaced the battery?

Zeeboyyombwe wrote:

Battery health drains fast in iOS 26

One of the last things Apple does before the official release of a new iOS version is optimizing battery performance. It is well know by users who actually know what’s going on that betas use more battery than the release candidate.

Your experience is perfectly normal. Next time stay away from the beta releases.

Click here and follow the instructions. This will only work during the beta period.

If this method produces an option to install 18,6, it's no longer possible to downgrade to 18.5.

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