Can I update the iOS on my iPhone 6 Plus?

Yes, you can update the iOS on your iPhone 6 Plus up to iOS 12.5.6.

But, that is the end of the line. There are no more updates available for your phone, so the phone cannot handle iOS 15 or iOS 16 if that might be what you are asking about.

An iPhone 6 Plus isn't capable of 13 or above. To install 12.5.6, use a computer or the Software Update function in Settings.

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