Quick Answer
On iPhone running iOS 18 or newer, open Settings, tap Apps, tap Messages, and switch on RCS Messaging. Your carrier must support it (the big four US carriers and most major UK and EU carriers do), and you must have a data connection.
On Android, open Google Messages, tap your profile picture in the top right, choose Messages settings, tap RCS chats, and turn on Turn on RCS chats. Wait for the status to show Connected.
What RCS actually changes
RCS (Rich Communication Services) is the modern replacement for SMS and MMS. It uses your data connection instead of the cellular voice channel, so it delivers high resolution photos and video, typing indicators, read receipts, larger group chats, and longer messages. Apple added RCS support in iOS 18, released in September 2024, and refined the encryption story in iOS 26 with end to end encryption for RCS chats between RCS users.
Before RCS, a text from an iPhone to an Android fell back to SMS or MMS, which crushed photos and split group chats. With RCS turned on both ends, those problems mostly go away.
Method 1: iPhone (iOS 18 and newer)
The toggle moved in iOS 18. It now lives under the Apps section, not the main Phone or Messages list.
- Open Settings.
- Scroll to Apps and tap Messages.
- Tap RCS Messaging.
- Turn on RCS Messaging.
You will see a confirmation message. RCS will not work unless your cellular carrier has updated its carrier bundle to support RCS, which all major US carriers (AT&T, Verizon, T-Mobile, US Cellular) and most major UK and European carriers have done by 2026. If the toggle is greyed out, your carrier is the bottleneck.
You can confirm it is working by opening a thread with an Android user. The text field placeholder will read "Text Message - RCS" instead of "Text Message - SMS", and you will see typing indicators and read receipts.
Method 2: Android via Google Messages
On every modern Android phone, Google Messages is the default app and it runs RCS through Google Jibe, which means you do not have to wait on your carrier.
- Open Google Messages.
- Tap your profile picture in the top right corner.
- Choose Messages settings.
- Tap RCS chats.
- Turn on Turn on RCS chats.
The status line will cycle through Setting up and then settle on Connected with a green tick. From that point any chat with another RCS user (including iPhone on iOS 18+) runs over RCS.
If you use Samsung Messages instead, the path is similar: Samsung Messages, then Settings, then Chat settings, then turn on Rich Communications.
What RCS does not fix
Blue versus green bubbles still exist on iPhone. Apple uses blue for iMessage and green for everything else, including RCS, and Apple has not signalled any intent to change that.
End to end encryption between iPhone and Android RCS chats arrived with iOS 26 and the Universal Profile 3.0 spec. If one side is on an older OS, the chat will fall back to standard RCS without end to end encryption, similar to how some chats fall back to SMS.
Reactions on iPhone show up as inline messages ("Tom loved a message") rather than the floating heart you see on iMessage, although this gap is closing.
What to check if RCS will not turn on
- Confirm your carrier is on the supported list. Search "[carrier name] RCS support" on a major news site.
- Make sure you are signed in to your Google account (Android) or your Apple ID (iPhone).
- Check you have a data connection. RCS will not register over wifi only on first set up; you usually need a moment on cellular.
- Restart the phone. The registration handshake sometimes needs a kick.
- On Android, make sure Google Messages is set as the default messaging app, not the manufacturer app.
Why this matters now
For most people the practical win is that family group chats no longer split into a Frankenstein mix of SMS and iMessage. You can share a real video of your kids, not a 360p smudge. You can see when the other person is typing. You can react without sending a separate text. And if you ever switch phone platforms, your messaging experience does not collapse.
The takeaway
Enabling RCS takes a single toggle on both iPhone and Android. On iOS 18 and newer it is in Settings under Apps, Messages, RCS Messaging. On Android it is in Google Messages, profile picture, Messages settings, RCS chats. Turn it on both ends and the green bubble experience gets dramatically better.
