What you see depends on the channel
The composer adapts to whichever channel you picked in step 1:
If you chose an SMS channel, you’ll see a text area and a message info panel for character counting.
If you chose a WhatsApp channel, you’ll see a template picker, variable editors, an optional header-media uploader, and a live preview.
The sections below cover each flow.
Composing an SMS message
The page header reads “SMS Message” with the subtitle “Compose your SMS message content.”
Write the SMS message
In the Message Content text area, type the SMS you want to send. The placeholder text says “Type your SMS message here…”
As you type, the Message Info panel on the right updates in real time.
Read the Message Info panel
Four values update live:
Character Set — displays either
GSMorUnicode. GSM covers plain Latin text and common punctuation. Unicode is selected automatically when your message includes emoji, accented characters, or non-Latin scripts.Message Length — the total character count of your message.
Max Length —
1600. This is the maximum characters a single SMS broadcast can contain.Message Parts — how many SMS segments your message will be split into when sent.
How SMS parts are calculated
SMS carriers bill and deliver in segments, so a longer message will be stitched together from multiple parts on the recipient’s phone.
For GSM messages: the first segment is 160 characters. Each additional segment is 153 characters.
For Unicode messages: the first segment is 70 characters. Each additional segment is 67 characters.
A single emoji switches the entire message to Unicode — which shortens every segment.
Tip: If you’re close to the segment boundary, try rewording to stay under 160 GSM characters or 70 Unicode characters. Fewer segments means fewer messages counted against your channel’s limits.
SMS character limits
Broadcasts allow messages up to 1,600 characters. Keep your text under that cap — otherwise the message cannot be sent.
Composing a WhatsApp template message
WhatsApp broadcasts can only use templates that have already been approved by WhatsApp. You won’t be able to type a free-form message here.
The page header reads “WhatsApp Template” with the subtitle “Choose your template and fill its variables with Intercom contact attributes.”
Pick a WhatsApp template
Under Select Template, open the dropdown (its placeholder is “Select a template…”). Only approved templates from this WhatsApp channel appear in the list.
Pick the template you want to use. The composer then expands to show one section per template part: header, body, buttons, and a preview.
Note: If the dropdown is empty, it means no templates are approved on this channel yet. Add and submit a template from the channel’s template library, wait for approval, then return to the broadcast.
Upload header media (when required)
If the selected template has a media header — image, video, or document — a Header Media section appears.
Choose how to provide the file: select Enter URL to paste a direct link, or select Upload File to upload from your computer.
Enter URL: paste a public URL (for example,
https://example.com/image.jpg) into the URL input.Upload File: click the “Click to upload” drop zone and select your file. A progress indicator appears while the upload runs.
Accepted file types depend on the template’s header:
Header type | Accepted files | Maximum size |
Image | JPEG or PNG | 5 MB |
Video | MP4 or 3GPP | 16 MB |
Document | 100 MB |
Fill in the template variables
Most templates include variables — placeholders like #{{1}}, #{{2}} that get replaced for each recipient. The composer shows one section per variable type:
Header Variables — variables inside a text header.
Body Variables — variables inside the template body. The section note says: “Enter the text for your message in the template language.”
Button Variables — variables inside interactive buttons (for example, a URL button with a dynamic slug).
For each variable you can either type a static value that everyone receives, or pull a value from each contact’s Intercom attributes:
By default the variable field accepts plain text — type the value and it’s used for every recipient.
To personalize per contact, tick the Use Intercom Attribute checkbox for that variable.
Pick an Intercom attribute (for example,
nameoremail) from the attribute dropdown.Enter a fallback value in the field next to it. If a contact doesn’t have that attribute set, the fallback value is used instead.
Example. For a template like “Hi #{{1}}, your order #{{2}} is ready!” you might map #{{1}} to the contact’s first name with fallback “there”, and type the actual order number into #{{2}} as a static value.
Check the live preview
The Preview panel on the right shows your message as a WhatsApp bubble: header media, body text with variables substituted, optional footer, and any buttons. It updates as you type, so use it to confirm formatting and catch mistakes before moving on.
Continue to review
When your message is complete:
Click Next to move to step 4, Review & Send.
Use Back if you need to re-check matched contacts or filters first.
What’s next
See the Channels section for WhatsApp template setup and approval