The iOS 26.5 RC is available now, along with the official release notes, and with them, Apple has confirmed that the update will bring a key RCS upgrade to the Messages app.
Messages app to support RCS end-to-end encryption in iOS 26.5

RCS messaging is the best way for iPhones to send messages with Androids. It brings several iMessage-style features to your conversations on the Green Bubble.
And in iOS 26.5, Apple confirmed that RCS messaging will now be more secure and private than ever.
Indeed, according to the company’s iOS 26.5 release notes, the update adds the following:
End-to-end encrypted RCS messaging (beta) in Messages is available from supported carriers and will roll out over time.
Before the public launch of iOS 26.5 (likely next week), Apple plans to list carriers that support RCS end-to-end encryption on this web page. However, the information is not yet available.
Apple offered end-to-end encrypted RCS messaging in the iOS 26.5 beta until now. But it was also featured in the iOS 26.4 beta before being removed before launch.
We suspected that Apple was planning to offer this feature in iOS 26.5, because it never warned otherwise: such a warning was issued during the beta version of iOS 26.4. It’s good to see the company officially confirm this.
End-to-end encryption for RCS is still classified as beta, but it will be available in the final release of iOS 26.5.
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