RCS
Rich Communication Services is carrier messaging with media, branding and read receipts where operators and handsets support it.
Definitions only — a term explained here is not a service we sell.
RCS is carrier messaging that adds media, branded senders and read receipts where the operator, handset and client support it. It is not a universal replacement for SMS, so a fallback path stays in place.
How RCS works
RCS runs over an IMS-based messaging platform, operated by the operator or hosted for it, and uses the GSMA Universal Profile so handsets and networks interoperate. A device checks whether a contact supports RCS, then upgrades the conversation to typing indicators, read receipts, group chat and media. Where the operator, handset or messaging client lacks support, the conversation falls back to SMS or MMS. The experience depends on the operator, the handset and the client.
Business messaging adds a verified sender, branded cards and suggested replies. The A2P SMS path stays for the numbers and devices RCS cannot reach, and the fallback has to be designed, not assumed. A read receipt is not proof of delivery, and consent and opt-out rules still apply.