With the introduction of RCS messaging on iPhone through the release of iOS 18, the GSM Association’s technical director hinted at the next significant milestone for the messaging standard: the implementation of interoperable end-to-end encryption. Six months have passed, and now the GSMA has published an updated specification for RCS messaging that incorporates end-to-end encryption (E2EE) based on the Messaging Layer Security (MLS) protocol. This new RCS profile ensures the confidentiality and security of messages and files exchanged between iOS and Android devices.

According to Tom Van Pelt, Technical Director of GSMA, “RCS will be the first large-scale messaging service to support interoperable E2EE between client implementations from different providers. Along with other unique security features such as SIM-based authentication, E2EE will provide RCS users with the highest level of privacy and security, protecting them from scams, fraud, and other security and privacy threats.” RCS, or Rich Communication Services, enables users to share images, videos, and audio clips across different platforms through text messages. Google’s RCS implementation has included default end-to-end encryption for both one-on-one and group chats since early 2024, provided all participants use Google Messages with RCS chats enabled. Meanwhile, iMessages already benefit from E2EE protection.

In a statement to 9to5Mac, Apple expressed its satisfaction with leading a cross-industry effort to integrate end-to-end encryption into the RCS Universal Profile published by the GSMA. The company also committed to adding support for end-to-end encryption to iOS, iPadOS, macOS, and watchOS in future software updates. Although a specific timeline has not been provided, once the update is rolled out, it will prevent third parties from intercepting and accessing potentially sensitive messages.