iOS 18 is rolling out today with RCS to improve the messaging experience between Android and iPhone. Support is not yet enabled for all carriers, including Google Fi Wireless.

In a statement, Google tells us that “only Apple has the ability to enable RCS interoperability for iPhone users on Fi.” The Google MVNO has already done the necessary work to support iPhone RCS on its end.

As of today’s launch of iOS 18, RCS is enabled on the major US carriers (AT&T, T-Mobile, and Verizon). Another MVNO where we don’t see it available is Mint Mobile.

Behind the scenes, our colleagues from 9to5Mac explain how carriers are required to send an updated file, known as a Carrier Bundle, to Apple stating that RCS support has been enabled. The iPhone maker can then distribute that file as an over-the-air update that doesn’t require a whole new version of the operating system.

Apple maintains a support document that lists “Wireless carrier support and features for iPhone” by country. This includes 5G, eSIM, VoLTE, and Wi-Fi Calling, but Apple does not currently specify the availability of RCS.

“We’ve been working to accelerate RCS adoption for a long time and are excited to see Apple take steps to adopt RCS with the launch of iOS 18. At launch, Fi users with an Android phone will be able to communicate via RCS with iPhone users who have RCS interoperability enabled. Only Apple has the ability to enable RCS interoperability for iPhone users on Fi, and we hope they will do so in the near future.”

— Google spokesperson

That said, starting today, Google Fi subscribers on Android “can communicate via RCS with iPhone users who have RCS interoperability enabled.”

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