What Is RCS Messaging and Why Does It Matter?

The GSMA, the global telecom industry body, developed the RCS standard as a carrier-native upgrade to SMS. Google has been the primary driver of RCS adoption on Android since 2019, when it began rolling out RCS through Google Messages. According to Google’s Messages blog, RCS is now available to over 1 billion monthly active users globally. Apple confirmed RCS support in a press release in late 2023 and shipped it with iOS 18, ending years of pressure from Android users, regulators, and even Google’s public campaign to push Apple toward adoption.

What does RCS actually do that SMS cannot?

SMS was designed in the 1980s and has not fundamentally changed since. It supports 160 characters of plain text per message, with no read receipts, no typing indicators, and no way to send full-resolution photos. MMS extended SMS to support images, but compresses them heavily (typically to under 600 KB) and limits video to a few seconds. RCS replaces both with a modern messaging protocol that works over your data connection or Wi-Fi instead of the cellular voice channel.

What changed when Apple added RCS to iPhone?

Before iOS 18, every text message between an Android phone and an iPhone was sent as SMS or MMS. This meant compressed photos, no read receipts, no typing indicators, and broken group chats. The green bubble experience was functionally stuck in 2005. With iOS 18, the built-in Messages app on iPhone now supports RCS when texting Android users. Photos arrive at full resolution, group chats work properly with named groups, and you can see when the other person is typing.

The change is automatic. If you have an iPhone running iOS 18 or later and your carrier supports RCS, texts to Android users who have RCS enabled will automatically upgrade to RCS. You do not need to change any settings. Your carrier handles the RCS connection in the background. The three major US carriers (AT&T, T-Mobile, Verizon) all support RCS on both Android and iPhone. If either person’s carrier does not support RCS, the conversation falls back to SMS/MMS automatically. For more on managing your messaging privacy, see our guide on phone privacy settings.

Does RCS replace iMessage?

No. iMessage and RCS are separate systems that coexist on iPhone. When you text another iPhone user, the conversation uses iMessage (blue bubbles). When you text an Android user, the conversation now uses RCS instead of SMS (still green bubbles, but with modern features). Apple did not change the bubble colors, and iMessage remains the default for iPhone-to-iPhone communication.

iMessage still has features that RCS does not support in cross-platform conversations. Tapback reactions (the heart, thumbs up, exclamation mark, etc.) from an iPhone appear as text descriptions on Android (“Alex loved your message”) rather than as visual reactions. iMessage apps, Memoji stickers, and Apple-specific effects (lasers, confetti, invisible ink) only work between iPhones. The practical improvement with RCS is that the baseline quality of Android-to-iPhone texting jumped from 1990s-era SMS to a modern messaging experience.

Is RCS messaging encrypted?

This is where it gets complicated. Google Messages supports end-to-end encryption for RCS conversations, but only when both people are using Google Messages on Android. According to Google’s encryption documentation, encrypted conversations show a lock icon next to the send button. When an Android user texts an iPhone user via RCS, the conversation is not end-to-end encrypted. The messages are encrypted in transit (between your phone and the carrier’s servers), but the carrier can technically read them.

Apple’s implementation of RCS on iPhone follows the GSMA’s Universal Profile standard, which does not mandate end-to-end encryption. The GSMA announced plans to add end-to-end encryption to the RCS Universal Profile in late 2024, but implementation timelines remain unclear. Until that standard is finalized and adopted by all carriers, RCS between Android and iPhone should not be considered private in the way that iMessage, Signal, or even Google Messages-to-Google Messages RCS conversations are. If privacy is your priority, dedicated messaging apps remain a better choice. Check our tech terms guide for more on encryption standards.

How do you enable RCS on your phone?

On Android with Google Messages: open Google Messages, tap your profile icon, then Settings, then RCS chats. Toggle “Turn on RCS chats” to on. If your carrier supports RCS, the feature activates within minutes. Samsung Messages also supports RCS through the same carrier infrastructure.

On iPhone with iOS 18 or later: go to Settings, then Messages. Look for “RCS Messaging” and toggle it on. If you do not see this option, your carrier may not yet support RCS on iPhone, or your iPhone may need a carrier settings update. Restart your phone and check again after 24 hours if the toggle is missing. Using our research methodology, we verified that all three major US carriers enabled RCS for iPhone within one week of the iOS 18 launch.

My honest take: RCS is not exciting. It is a correction. Texting between Android and iPhone should have been this good a decade ago. The fact that Apple took until 2024 to adopt it was a deliberate product strategy, not a technical limitation. But now that it is here, the practical benefit is real. If you regularly text people on the other platform, you will notice better photos, working group chats, and typing indicators immediately. It does not make Android-to-iPhone texting as seamless as iMessage-to-iMessage, but it closes about 80% of the gap. For related privacy-conscious app recommendations, see our VPN picks.