RCS Message Types
RCS (Rich Communication Services) gives you a significantly richer toolkit than SMS or MMS, and the same interactiveness you know from WhatsApp. Rather than sending plain text, you can send interactive cards, media-rich messages, and conversational prompts that feel closer to an in-app experience than a traditional text message.
This guide covers every RCS message type available in charles, when to use each one, and what to keep in mind when building with them.
Text Messages
The simplest message type — a plain text body, just like SMS. The key difference in RCS is that text messages support longer character limits, basic formatting in some implementations, and are delivered with read receipts and typing indicators enabled.
When to use it: Transactional alerts, simple notifications, fallback content, or any situation where the message itself doesn't need visual treatment.
Things to know:
No hard 160-character limit like SMS
Read receipts and delivery confirmation are available by default
Still subject to carrier-specific display differences
Rich Cards
A rich card is a single, visually structured message unit containing a combination of media and text. Think of it as a small content card — similar to what you'd see in a social feed or a chat app like iMessage or WhatsApp.
A rich card can include:
Media — an image, GIF, or video (landscape or portrait orientation)
Title — a short headline
Description — supporting body text
Suggested actions — buttons the recipient can tap (see Suggested Actions below)
When to use it: Product highlights, appointment confirmations with an image, event announcements, or any time a single piece of content benefits from visual framing.
Things to know:
Cards can be either standalone (one card per message) or grouped into a carousel (see below)
Landscape cards (wider format) work better for media-heavy content; portrait cards work better for text-heavy content
Media files should be hosted on a publicly accessible HTTPS URL
File size limits vary by carrier; aim for under 1MB for images
Carousels
A carousel is a horizontally scrollable set of rich cards sent together in a single message. Recipients swipe through them, and each card can have its own media, title, description, and action buttons.
When to use it: Product catalogs, multiple offers in a single promotion, step-by-step instructions, or presenting options side by side (e.g., three appointment slots, four service tiers).
Things to know:
Minimum of 2 cards, maximum of 10 cards per carousel
All cards in a carousel must use the same orientation (all landscape or all portrait)
Keep titles and descriptions consistent in length across cards — uneven content creates visual imbalance
Each card's suggested actions are independent, so a recipient can tap the button on card 3 without scrolling back to card 1
Suggested Replies
Suggested replies are pre-written response chips that appear beneath a message. The recipient taps one and it sends as their reply — no typing required.
When to use it: Guiding conversations through a known decision tree, collecting preferences, confirming or declining something, or anywhere you want to reduce friction in a response.
Example: After sending an appointment reminder, display chips for Confirm and Reschedule.
Things to know:
Up to 11 suggested replies or actions can be displayed at once (combined total)
The chip text should be short — 25 characters or fewer is a good rule of thumb
Once tapped, the chip text is sent as the user's message and is visible in the conversation thread
Suggested replies are conversational — they disappear after one is tapped
Suggested Actions
Suggested actions look identical to suggested replies but trigger a device-level behavior instead of (or in addition to) sending a text reply. They're tappable buttons that can:
Action Type | What it does |
Open URL | Opens a web page in the device browser |
Share Location | Prompts the user to share their current location |
Open Maps | Opens a location in the device maps app |
Send Reply | Sends a predefined text back to the agent (same as suggested reply) |
When to use it: Deep-linking to a checkout page, starting a call with a support team, navigating a customer to a store location, or adding an event to a calendar directly from a message.
Things to know:
Actions and replies share the same 11-chip limit per message
On unsupported devices, action buttons may not render — always consider whether your fallback SMS version makes sense without them
URL actions should always use HTTPS
Standalone Rich Media
While media is often embedded inside a rich card, you can also send a standalone media message — just an image, GIF, audio clip, or video file with no card wrapper.
When to use it: Simple visual confirmation (e.g., a QR code, a receipt image, a map screenshot), or when the media itself is the full message and a card structure would add unnecessary padding.
Things to know:
Supported formats vary by carrier, but JPEG, PNG, GIF, and MP4 are broadly supported
Audio messages are supported in some RCS implementations but not universally
Standalone media doesn't support suggested actions — use a rich card if you need buttons alongside media
Comparing Message Types at a Glance
Message Type | Media | Title/Text | Action Buttons | Scrollable |
Text | — | ✓ | — | — |
Rich Card | ✓ | ✓ | ✓ | — |
Carousel | ✓ | ✓ | ✓ | ✓ |
Suggested Reply | — | — | ✓ (text reply) | — |
Suggested Action | — | — | ✓ (device action) | — |
Standalone Media | ✓ | — | — | — |