What is the difference between iMessage, RCS, and SMS/MMS?
You can use the Messages app on your iPhone, iPad, Mac, Apple Watch, or Apple Vision Pro to send messages. Those messages are sent as iMessage, RCS, or SMS/MMS. Learn more about the difference between the message types.
iMessage
iMessages can be sent to another iPhone or another Apple device over Wi-Fi or cellular-data networks. With iMessage, you can send texts, high resolution photos and videos, documents, links, Tapbacks, text effects, Live Stickers, message effects, and more. iMessage supports delivery and read receipts and typing indicators. iMessages appear in blue text bubbles on your device.
When you use iMessage, your conversations are encrypted end-to-end, so they can’t be read while they’re sent between devices.
To turn iMessage on or off, go to Settings > Apps > Messages.
If Wi-Fi is unavailable, iMessages will be sent over cellular data. Cellular data rates might apply.
RCS
If you aren’t using iMessage, you can use RCS. RCS text messages can be sent to non-Apple devices as well as another iPhone or another Apple device with Text Message Forwarding turned on. With RCS, you can send texts, high resolution photos and videos, links, and more. RCS also supports delivery and read receipts and typing indicators. RCS messages appear in green text bubbles on your device.
Apple’s implementation of RCS is based on the industry’s standard. RCS messages aren’t end-to-end encrypted, which means they're not protected from a third-party reading them while they're sent between devices.
RCS is a carrier-provided service. When your device connects to your cellular network, it communicates with your carrier and their partners to set up RCS. User identifiers are exchanged for your carrier and their partners to authenticate your device and provide a connection. These identifiers could include but are not limited to your IMEI, IMSI, current IP address, and phone number. Your current IP address might also be shared with other RCS users.
To use RCS, you need iOS 18 and a text-messaging plan from a carrier that supports RCS on iPhone. Contact your wireless carrier for more information.
To turn RCS on or off, go to Settings > Apps > Messages > RCS Messaging.
There may be a delay of a few hours in activating RCS.
SMS/MMS
If you aren’t using iMessage or RCS, you can use SMS/MMS. SMS and MMS text messages can be sent to non-Apple devices as well as another iPhone or another Apple device with Text Message Forwarding turned on. With SMS/MMS, you can send texts, photos and videos, links, and more. SMS/MMS messages appear in green text bubbles on your device.
SMS/MMS messages aren’t end-to-end encrypted, which means they're not protected from a third-party reading them while they're sent between devices.
SMS and MMS are carrier-provided services. When your device connects to your cellular network, it communicates with your carrier. User identifiers are exchanged for your carrier to authenticate your device. These identifiers could include but are not limited to your IMEI, IMSI, current IP address, and phone number.
To use SMS/MMS on an iPhone, you need a text-messaging plan that supports these services. Contact your wireless carrier for more information.
