iOS 18 launches today with RCS to improve the messaging experience between Android and iPhone, but support isn’t enabled for all carriers yet, including Google Fi Wireless.

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

Since the launch of iOS 18 today, RCS is enabled on the major US carriers (AT&T, T-Mobile, and Verizon). Another MVNO where we believe it is not available is Mint Mobile.

Behind the scenes our colleagues from 9to5Mac explain how mobile operators must send an updated file, called a carrier bundle, to Apple indicating that RCS support is enabled. The iPhone maker can then distribute this file as an over-the-air update that does not require a completely new version of the operating system.

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

“We have long been working to accelerate RCS adoption and are excited to see Apple taking steps toward RCS adoption with the launch of iOS 18. At launch, Fi users with an Android phone will be able to communicate over RCS with iPhone users who have RCS interoperability enabled. Only Apple can enable RCS interoperability for iPhone users on Fi and we hope they will do so in the near future.”

— Google spokesperson

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

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