Is RCS End-to-End Encrypted? iPhone to Android, Google Messages, Samsung and SMS Fallback Explained

Sometimes. RCS itself does not guarantee end-to-end encryption. Google Messages has encrypted RCS chats end to end between its own users for years, using the Signal Protocol. Since 11 May 2026, chats between an iPhone on iOS 26.5 or later and Android phones running Google Messages can be end-to-end encrypted too, following the GSMA's MLS-based RCS standard, but only when both people's carriers support it, and Apple still labels it beta. Samsung Messages, business messages and anything that falls back to SMS or MMS are not end-to-end encrypted. Look for the lock icon before you assume a chat is private.

Sources: What is the difference between iMessage, RCS and SMS/MMS?, Apple Support (published 11 May 2026); How end-to-end encryption in Google Messages provides more security, Google Messages Help; RBM data security, Google for Developers. Full list at the end.

What RCS Is, and Why Encryption Was Missing

RCS (Rich Communication Services) is the carrier messaging standard meant to replace SMS and MMS. It adds typing indicators, read receipts, high-resolution photos and proper group chats, and it travels over data or Wi-Fi through servers run by carriers and Google. The GSMA, the mobile industry body, publishes the specification as the RCS Universal Profile.

For most of its life the Universal Profile had no end-to-end encryption. Messages were protected in transit to the RCS servers, but the servers could read them. Google filled the gap only inside its own app, which is why the answer to "is RCS encrypted?" has depended on which app is on each end of the chat.

Universal Profile 3.0: End-to-End Encryption Built on MLS

On 14 March 2025 the GSMA announced new RCS specifications that include end-to-end encryption based on the Messaging Layer Security (MLS) protocol, the IETF standard published as RFC 9420. The GSMA called encryption "the cornerstone of the new RCS Universal Profile release" (Universal Profile 3.0) and said it makes RCS "the first large-scale messaging service to support interoperable E2EE" between clients from different vendors.

Apple told 9to5Mac the same day that it had "helped lead a cross industry effort" to bring end-to-end encryption to the Universal Profile, and that it would add support for end-to-end encrypted RCS to iOS, iPadOS, macOS and watchOS "in future software updates." Google said it would support the updated specification too.

MLS is built for groups: members share a tree of keys, so adding or removing someone doesn't mean re-encrypting to every member one by one. We compare it with the Signal Protocol in libsignal vs MLS: secure messaging explained.

iPhone to Android: What Shipped in iOS 26.5

Apple and Google turned on end-to-end encrypted RCS between iPhone and Android on 11 May 2026. Apple's announcement says it is "rolling out in beta for iPhone users running iOS 26.5 with supported carriers and Android users on the latest version of Google Messages." It is on by default, and both companies say it "will be automatically enabled over time for new and existing RCS conversations," so an older thread may not switch over straight away.

The carrier is the catch. Apple's support page says RCS messages can be end-to-end encrypted "when all participants have carriers that support encryption," and that each conversation "depends on whether your contact's carrier also supports it." Apple's carrier pages mark "End-to-end encrypted RCS messaging (beta)" for each carrier that supports it. When we checked them on 5 November 2026 (most were last updated in September 2026), they included the major carriers in the United States and Canada, a number of European carriers (including Telekom, O2 and 1&1 in Germany and BT and EE in the UK), au and SoftBank in Japan, Singtel in Singapore, and TIM and Vivo in Brazil. Apple's pages for Africa, the Middle East and India listed no carrier with encrypted RCS. Check Apple's carrier list for your own carrier, because it changes.

On iPhone the setting lives in Settings, Apps, Messages, RCS Messaging, where End-to-End Encryption (Beta) can be turned on or off. As of Apple's support pages in September 2026, the feature is still labelled beta, and we found no Apple announcement since then that removes the label.

Apple's 2025 statement named iPadOS, macOS and watchOS as well, but its May 2026 announcement and support pages describe only the iPhone, so we can't confirm encrypted RCS on those devices.

Google Messages: Signal Protocol Between Android Users

Google Messages has offered end-to-end encrypted RCS between its own users for years, and it doesn't use MLS for this. Google's technical paper (version 1.2, February 2022) says Messages "uses the Signal Protocol to build E2EE for RCS messages." Attachments are encrypted on the phone with a fresh key before they are uploaded to the carrier's content store.

According to Google's help page, encryption is automatic when you and the person or group you message all use Google Messages, have RCS chats turned on, and are on data or Wi-Fi. Each encrypted conversation has a verification code you can compare with your contact. If either side loses RCS, the chat drops to SMS, which is not encrypted, and switches back to encrypted RCS once both sides have RCS again.

Google's help page, as we read it on 5 November 2026, still says "Currently only Google Messages supports end-to-end encrypted RCS." That line predates the iPhone rollout, but it remains the only vendor statement we found about other Android apps.

Samsung Messages and Other Android Apps

Apple and Google both name Google Messages as the Android requirement for encrypted chats with iPhones, and Google says only its app supports end-to-end encrypted RCS. We found no Samsung documentation of end-to-end encryption in Samsung Messages, so treat chats in Samsung Messages, or in any other Android RCS app, as not end-to-end encrypted.

In the US, Samsung has ended Samsung Messages: its end-of-service notice says the app was discontinued in July 2026 and tells users to make Google Messages their default. The notice applies to the US market only, and devices on Android 11 or lower are not affected.

Group Chats

Between Google Messages users, group RCS chats are end-to-end encrypted on the same terms as 1:1 chats: everyone in the group needs Google Messages and RCS turned on.

For groups that mix iPhones and Android phones, the documentation is thin. Apple's rule is that RCS can be encrypted "when all participants have carriers that support encryption," which means one member on an unsupported carrier, an older iOS version or a different Android app should leave the whole group unencrypted. Neither Apple nor Google spells out how mixed groups behave, so check the indicator in each group rather than assuming.

Business Messages (RBM) Are Not End-to-End Encrypted

Messages from companies, such as delivery updates, bank alerts and booking confirmations, often arrive as RCS Business Messaging (RBM). Google's developer documentation is direct: "No, RBM doesn't offer end-to-end encryption." Messages are encrypted between your phone and Google's servers and stored encrypted at rest, but Google manages the keys and businesses can't control them.

Google's servers also hold these messages for a while: messages from a business are kept until delivered for up to 30 days, may be kept 14 days after delivery for spam and abuse detection, and media files are stored for 60 days. Your replies to a business are held for up to seven days.

SMS Fallback Is Never Encrypted

When RCS isn't available, because someone has no data, has RCS turned off, or uses a phone or carrier without RCS, your phone sends the message as SMS or MMS. Google says plainly that "End-to-end encryption isn't available for SMS/MMS messages." SMS travels through carrier networks that can read it.

On Android, Google Messages lets you control what happens when end-to-end encryption isn't available, so you can choose to wait for RCS instead of sending a plain text. On iPhone, green bubbles are used for both RCS and SMS/MMS, so bubble colour alone won't tell you which one you're on.

How to Tell If an RCS Chat Is Encrypted

• iPhone (Apple Messages): Apple says an end-to-end encrypted RCS conversation shows "Encrypted" with a lock icon at the top. "If you don't see the indicator, your RCS messages aren't protected" from being read in transit. iMessage chats (blue bubbles) also show a lock icon at the top.
• Android (Google Messages): a lock on the send button while you type and next to the message timestamp means the chat is end-to-end encrypted. Google says cross-platform chats with iPhones use the same lock icon. RCS messages are dark blue and SMS/MMS messages are light blue.
• Verify the contact: Google Messages shows a verification code for each encrypted conversation; if it matches on both phones, nobody is sitting in the middle.
• No lock: treat the chat as not end-to-end encrypted, whatever app or bubble colour you see.

What End-to-End Encryption Doesn't Cover

Encrypted RCS still runs through carrier and Google servers. Google's technical paper lists the metadata those servers can still see, including the phone numbers of sender and recipient, message timestamps, IP addresses, both carriers, device details in protocol headers, whether a message has an attachment, and the approximate size of messages. The EFF made the same point about the iPhone rollout: metadata will likely still be collected and stored.

Messages are also only as private as the phones they land on. On Android, Google says end-to-end encrypted messages are stored in the device's message database, included in Android backup, and readable by apps you have given SMS or notification access.

For how RCS compares with dedicated messaging apps, see which messaging apps are end-to-end encrypted and is Telegram end-to-end encrypted?

Frequently Asked Questions

When the Conversation Is for Work

RCS encryption depends on your app, your contact's app and both carriers, and it can drop to SMS without much warning. For team and business conversations, Lupyd end-to-end encrypts direct messages with the Signal Protocol and group channels with MLS by default, with keys kept on your devices; group calls are not yet end-to-end encrypted, and Lupyd has not had an external security audit yet. Try Lupyd.

Final Takeaway

RCS can be end-to-end encrypted, but it isn't by itself. Google Messages to Google Messages chats are encrypted with the Signal Protocol, and since May 2026 iPhone to Google Messages chats are encrypted with MLS in beta when both carriers support it. Samsung Messages, business messages and SMS fallback are not. The only reliable signal is the lock icon in the conversation.

Sources & References

• RCS Encryption: A Leap Towards Secure and Interoperable Messaging, GSMA, 14 March 2025
• RFC 9420: The Messaging Layer Security (MLS) Protocol, IETF, July 2023
• Apple statement on end-to-end encrypted RCS, 9to5Mac, 14 March 2025
• End-to-end encrypted RCS messaging begins rolling out today in beta, Apple Newsroom, 11 May 2026
• End-to-end encrypted RCS messaging begins rolling out today for Android and iPhone users, Google, 11 May 2026
• What is the difference between iMessage, RCS and SMS/MMS?, Apple Support, published 11 May 2026
• Turn on RCS messaging on your iPhone, Apple Support, published 11 May 2026
• Wireless carrier support and features for iPhone in the United States and Canada, Apple Support, 15 September 2026, with the regional pages for Europe, Asia-Pacific, Latin America and the Caribbean, Africa and the Middle East and India
• How end-to-end encryption in Google Messages provides more security, Google Messages Help, read 5 November 2026
• Messages End-to-End Encryption Overview, Google technical paper, version 1.2, February 2022
• RBM data security, Google for Developers
• Samsung Messages End of Service Announcement, Samsung US
• Victory! End-to-End Encrypted RCS Comes to Apple and Android Chats, EFF, 12 May 2026

Last updated: 5 November 2026.