RCS messaging adds end-to-end encryption between Android and iOS

When RCS messaging became available on the iPhone with the rollout of iOS 18, the technical director of the GSM Association teased that the next major milestone for the messaging standard is the addition of interoperable end-to-end encryption. Now, six months later, GSMA has released an updated set of specifications for RCS messaging, which includes end-to-end encryption (E2EE) based on the Messaging Layer Security (MLS) protocol. The new RCS profile will ensure that messages and files remain safe and confidential when sent between iOS and Android devices. 

"...RCS will be the first large-scale messaging service to support interoperable E2EE between client implementations from different providers. Together with other unique security features such as SIM-based authentication, E2EE will provide RCS users with the highest level of privacy and security for stronger protection from scams, fraud and other security and privacy threats," said Tom Van Pelt, the Technical Director of GSMA. RCS, or Rich Communication Services, gives people a way to send images, videos and audio clips to each other through text across different platforms. Google’s implementation of RCS has had default end-to-end encryption for both one-on-one and group chats since early 2024, but only if all participants are using Google Messages with RCS chats turned on. Meanwhile, iMessages are already protected by E2EE.

In a statement sent to 9to5Mac, Apple said that it was "pleased to have helped lead a cross industry effort to bring end-to-end encryption to the RCS Universal Profile published by the GSMA." It also vowed to add support to end-to-end encryption to iOS, iPadOS, macOS and watchOS "in future software updates." Without a definite timeframe, it's hard to say when Apple is rolling out an update to support the security feature, but when it does, it will prevent third parties from intercepting and accessing potentially sensitive and private messages.