# Rich Communication Services (RCS)

> RCS is the carrier messaging standard that adds rich media, read receipts and verified business messages to the phone's built-in messaging app. How it differs from SMS.

Canonical: https://mobilevalidate.com/glossary/rcs · Last updated: 2026-09-25

![A phone with chat bubbles; one messaging-app check says registered, another is unknown.](https://mobilevalidate.com/images/messaging-app-registration-check.svg)

*Messaging-app checks answer registered, not registered or unknown, with the time we checked.*


Rich Communication Services (RCS) is a messaging standard that upgrades the phone's built-in text messaging app with chat features: high-resolution photos and videos, typing indicators, read receipts, group chats and, for businesses, verified branded messages with buttons and cards. It is the carrier industry's successor to SMS and MMS, specified by the GSMA as the **Universal Profile**.

## How does RCS work?

RCS messages travel over mobile data or Wi-Fi, not over the signalling channels used by SMS. Before a chat starts, the sending phone runs **capability discovery** to find out whether the other number supports RCS. If it does, the message goes as RCS. If not, the app falls back to SMS or MMS.

According to the [GSMA](https://www.gsma.com/solutions-and-impact/technologies/networks/rcs/universal-profile/), the Universal Profile is "a single, industry-agreed set of features and technical enablers". Its core features include capability discovery, chat, group chat, file transfer, audio messaging, and enablers for business messaging such as rich cards, privacy control and spam protection. Operators decide whether to deploy RCS in 4G networks, while 5G standards make it part of 5G networks and devices.

On Android, RCS is part of the default messaging app. Apple added RCS support in iOS 18 in 2024, where the carrier supports it.

## What is RCS business messaging?

Businesses can send RCS messages as a verified sender that shows a brand name, logo and verification mark. Messages can include carousels, suggested replies and action buttons, such as "track parcel" or "reschedule". Like other [A2P messaging](/glossary/a2p-sms), RCS business messaging needs sender verification and approval, and should only be used for messages people agreed to receive.

## How is RCS different from SMS and messenger apps?

| | SMS | RCS | Messenger apps |
|---|---|---|---|
| Built into the phone | Yes | Yes, where supported | No, needs an app and an account |
| Transport | Signalling network | Mobile data or Wi-Fi | Mobile data or Wi-Fi |
| Rich media and receipts | No | Yes | Yes |
| Verified business sender | Limited (sender IDs vary by country) | Yes | Yes, on business platforms |
| Reach | Every mobile phone | Depends on carrier, handset and settings | Depends on who installed the app |

## Why does RCS capability change?

Capability depends on the carrier, the handset, the messaging app version and whether the user has RCS turned on. A new phone, a SIM moved to another device or a changed setting can switch it on or off. Treat a capability answer as fresh for a short time only.

## How does MobileValidate check RCS?

The [RCS capability check](/services/rcs-capability-check) answers, per number, whether it can currently receive RCS messages: `registered: true`, `false` or `null` for unknown. When reported, it adds the handset platform (`ios` or `android`). Nothing is sent to the number, and inconclusive answers are free. Teams use it to route opted-in customers to RCS and send SMS to the rest, next to checks such as [iMessage](/services/imessage-number-check) and [WhatsApp](/services/whatsapp-number-check). See [channel selection](/use-cases/channel-selection).

## Frequently asked questions

### Is RCS the same as SMS?

No. SMS travels over the mobile network's signalling channels and carries short plain text. RCS runs over mobile data or Wi-Fi and supports media, typing indicators, read receipts and business features. When RCS is unavailable, phones fall back to SMS or MMS.

### Do iPhones support RCS?

Yes, since iOS 18 in 2024, where the user's carrier supports it.

### Do I need an app to use RCS?

No. RCS lives in the phone's default messaging app. It must be supported by the carrier and the handset, and turned on by the user.