Apple has begun testing end-to-end encryption for Rich Communication Services (RCS) messages exchanged between iPhones and Android devices, a move signaling a significant step toward bolstering security for cross-platform conversations. The feature, currently available in iOS 26.4 Developer Beta 2, utilizes the Messaging Layer Security (MLS) protocol as defined by the GSMA’s RCS Universal Profile 3.0 standard.
The testing phase allows developers to manually enable the encryption within the settings of the beta operating system. Users must navigate to Settings > Messages > RCS Messaging and toggle on “End-to-End Encryption (Beta).” On the Android side, participation in the Google Messages beta program is required to establish encrypted RCS communication with the updated protocol, according to Apple’s documentation.
This development addresses a long-standing security disparity in mobile messaging. While iMessage conversations between Apple devices are already protected by the company’s PQ3 encryption and Android-to-Android RCS messages through Google Messages utilize the Signal protocol, RCS messages between iPhones and Android phones have previously lacked end-to-end encryption. The new implementation aims to close this gap, ensuring messages cannot be read by third parties while in transit.
The GSMA first announced the availability of specifications for RCS that include end-to-end encryption based on the MLS protocol in March 2025, celebrating the integration of RCS with Apple’s iOS 18 as a culmination of collaborative efforts across the mobile industry. Tom Van Pelt, Technical Director at GSMA, noted at the time that RCS would be the first large-scale messaging service to support interoperable E2EE between client implementations from different providers.
Apple cautions that the feature remains in beta and is not included in the current public release of iOS. The company states that end-to-end encryption for RCS will be rolled out to customers in future updates to iOS, iPadOS, macOS, and watchOS 26. Apple notes that the feature will not be universally available on all devices or through all carriers initially, with support being rolled out in stages.
The move follows years of pressure on Apple to adopt RCS, with Google publicly urging the company to move beyond SMS and MMS protocols to improve security and functionality for cross-platform messaging. Apple added RCS support to iPhones with the release of iOS 18 in September 2024, but the implementation of end-to-end encryption has been a subsequent step.
Apple has not yet provided a specific timeline for the stable rollout of end-to-end encrypted RCS messaging beyond its commitment to include it in a future platform update.
