SMS Messaging #

Send and receive text messages (SMS) through the platform, and receive incoming multimedia messages (MMS). SMS is powered by Twilio, a leading phone service provider, giving you reliable coverage and phone number availability worldwide.

Overview #

SMS messaging in the app allows you to:

• Send and receive text messages with contacts
• Receive multimedia messages (images, videos, documents) via MMS
• Automate responses with an AI Agent
• Run SMS-based Broadcasts, including bulk outgoing sends
• Handle regulatory compliance for different countries

How SMS Works #

SMS requires you to connect your own Twilio account. SMS in most countries is heavily regulated — for example A2P 10DLC in the US (a registration system carriers use to confirm a business is really who it says it is, so its texts aren’t blocked as spam), brand registration in Australia, sender ID approval in Europe, etc. — and compliance has to be filed in the message sender’s own name. For that reason the platform does not offer managed SMS numbers — you bring your Twilio account, you pay Twilio directly for numbers and per-message fees, and the platform takes care of routing, AI, and the conversational layer on top.

What you get once connected:

• Global coverage across every country Twilio supports
• Number types including local, mobile, and toll-free
• Incoming MMS support — media a contact sends you is saved to the conversation (sending outbound MMS is not supported; outgoing SMS is text-only)
• No credit charge from the platform for SMS delivery — you only pay Twilio’s per-segment carrier fees directly. If an AI Agent generates the reply, that AI response still uses AI credits, the same as on any other channel.

WhatsApp Business API is different. WhatsApp Business API numbers can run on the platform’s managed Twilio or on your own Twilio. If you have connected your own Anthropic key (BYOK), managed-Twilio WhatsApp messages cost 0.05 credits each, inbound and outbound. On every other account those delivery costs are already covered by your AI credit rate, so there is no separate per-message charge. See WhatsApp Business for that path.

Don’t confuse this with the Twilio Account card. The Channels page also has a separate Twilio Account card, further down the list from SMS via Twilio. It switches your platform-bought WhatsApp numbers to your own Twilio account and is unrelated to the SMS connection on this page — switching it does not touch your SMS number. See SMS Provider for that card’s full walkthrough.

No Twilio? Use your own Android phone (Beta). For low-volume, conversational texting you can skip Twilio entirely and send SMS through your own Android phone and carrier plan. See Android Phone as SMS Gateway. It’s best for one-to-one replies and AI conversations — bulk SMS Broadcasts still require Twilio.

Connecting Your Twilio Account #

1. In the left sidebar, click Settings near the bottom.
2. In the Settings left rail, under Channels, click Channels.
3. Find the SMS via Twilio card and click Connect. (On the Channels page, this card sits further down the list, below Telegram, LINE, and the other channel cards.)

Connecting is a single form, not a multi-step wizard:

1. Account SID — paste it from your Twilio Console, under Account.
2. Auth Token — paste it from the same place, under Account → API credentials. It’s validated against Twilio and never shown back to you afterward.
3. Phone number — the SMS-capable number in your Twilio account, in international format (e.g. +14155552671).
4. Click Connect Twilio. The app validates the credentials and wires up the inbound webhook on your Twilio number automatically — there’s no separate webhook-setup or test-message step.

Once connected, the card shows your number and a masked Account SID, plus Edit and Disconnect actions. Right after connecting (or editing), the webhook URL the app configured is shown once for reference — it isn’t stored, so if you need to see it again, click Edit and re-enter the same credentials.

Where to find your Account SID and Auth Token: log in to console.twilio.com. Both are on the main dashboard in the Account Info panel. You buy and manage SMS numbers directly in the Twilio Console — the platform doesn’t have its own number-shopping UI for SMS.

You connect one Twilio number at a time. To use a different number, click Edit on the connected card and enter the new credentials — the old number is disconnected and the new one is configured.

Updating or Disconnecting SMS #

To change your SMS number or Twilio credentials, open SMS via Twilio on the Channels page, click Edit, and re-enter all three fields (Account SID, Auth Token, and phone number — the form always needs all three, since the auth token is never sent back to the browser to pre-fill). To stop using SMS, click Disconnect; this clears the inbound webhook on your Twilio number and removes the connection. Existing conversations are not deleted.

Sending and Receiving SMS #

Receiving Messages #

Once your number is active, incoming SMS messages are automatically routed to the platform:

1. A contact sends a text to your phone number.
2. The message appears in Chats in real time.
3. A new contact is created automatically if this is the first message from that sender.
4. If an AI Agent is handling the relevant conversation, it responds automatically.

Sending Messages #

• Manual reply: Open a conversation in Chats and type your reply.
• Broadcasts: Set up a bulk SMS broadcast to reach contacts at scale — SMS is fully supported as an outgoing channel, just like WhatsApp. See Broadcasts.
• AI Agent: Assign an Agent to respond to incoming messages automatically.
• Scheduled messages: Schedule messages to send at a specific time.

MMS (Multimedia Messages) #

SMS numbers support incoming MMS, so when a contact sends you media it is saved to the conversation:

• Images (JPEG, PNG, GIF)
• Videos (MP4)
• Audio files
• Documents (PDF)

Media attachments are automatically saved and accessible in the conversation view. Sending outbound MMS from the platform is not currently supported — outgoing SMS is text-only.

Adding a Click-to-Text (SMS) Link to Your Website #

There’s no floating SMS widget like there is for WhatsApp, but you can still put a button or link on your website (or in an email, QR code, etc.) that opens the visitor’s messaging app with your number ready to text. This uses a plain sms: link.

The format is:

sms:+NUMBER

Use your number in international format, including the plus sign. For example:

sms:+15551234567

Putting it on a button #

Link any button or text to that address:

<a href="sms:+15551234567">Text us</a>

In a website builder (Wix, Squarespace, WordPress, Webflow, etc.), add a button as usual and paste sms:+15551234567 into its “link” / “URL” field.

Pre-filling a message #

You can pre-fill the message the visitor will send. iPhone and Android expect this slightly differently, so use this combined form to cover both:

sms:+15551234567?&body=Hi!%20I%20have%20a%20question

Spaces in the message must be written as %20.

Good to know.

• Click-to-text links only do something on a device that has a texting app — they work on phones, but on a desktop computer clicking the link usually does nothing.
• These links open the visitor’s own texting app; the first message comes from the visitor’s phone number, not yours. The conversation then appears in Chats like any other incoming SMS once they hit send.
• Avoid putting an sms: link inside an SMS you send — most phones won’t make it tappable. They work best on web pages, emails, and QR codes.

Voice Calls to Your SMS Number #

Voice calls to your connected Twilio SMS number are handled entirely by your own Twilio account — the platform does not install a voicemail greeting, recording, or transcription on numbers you bring. If you want voicemail on your SMS number, configure it in your Twilio Console.

Regulatory Compliance #

SMS regulation is handled directly with Twilio in your own account. The platform does not file compliance on your behalf for SMS — that has to be in your business’s name. Common requirements:

• A2P 10DLC (United States) — register your brand and campaign with The Campaign Registry through Twilio before sending to US numbers.
• Toll-Free verification (United States and Canada) — required for toll-free SMS sending.
• Sender ID registration (much of Europe, Middle East, Asia-Pacific) — Twilio handles the submission process.
• Identity documents (regulated countries like Germany, France, India, etc.) — uploaded in your Twilio Console when buying a number.

If your account needs a formal regulatory bundle (US toll-free, UK mobile, and similar), the Regulatory compliance card on the Channels page starts and tracks that submission with Twilio.

See Twilio’s regulatory guidelines for the full per-country breakdown.

Messaging Compliance Best Practices #

• Obtain consent before sending SMS messages to contacts. This is legally required in most jurisdictions (TCPA in the US, GDPR in Europe, etc.).
• Include opt-out instructions in broadcast messages (e.g., “Reply STOP to unsubscribe”).
• Respect opt-out requests immediately.
• Identify yourself in messages — recipients should know who is contacting them.
• Follow local regulations for the countries where your contacts are located.

Troubleshooting #

Messages Not Being Delivered #

• Verify the recipient’s phone number is in the correct international format (e.g., +1234567890).
• Check that your Twilio account has a positive balance and the connected credentials are still valid.
• Ensure the number has not been deactivated or released in your Twilio Console.
• Check the message status in the conversation view for error details — Twilio error codes are surfaced directly, and each one is explained in the Error Log.
• Some countries block messages from foreign numbers — buy a local Twilio number for that country.

Number Not Sending or Receiving #

• Confirm the number is active in your Twilio Console.
• Confirm the Twilio credentials connected on the Channels page still match the account that owns the number.
• For regulated countries, confirm A2P 10DLC, sender ID, or other Twilio compliance steps have completed.

MMS Not Working #

• Confirm MMS is supported in the recipient’s country.
• Check that the file size is within limits (typically 5MB for MMS).
• Verify the file format is supported (JPEG, PNG, GIF, MP4, PDF).

Not Receiving Incoming Messages #

• Send a test SMS to your phone number from your personal phone.
• Check that the number shows connected on the Channels page.
• If the issue persists, try reconnecting the number from the SMS via Twilio card — the platform re-runs the technical setup automatically.

Best Practices #

• Use local numbers for the countries where your contacts are based. Messages from local numbers have higher trust and delivery rates.
• Keep messages concise. SMS has a 160-character limit per segment. Longer messages are split into multiple segments, which increases cost.
• Don’t rely on emojis or special symbols. To keep each SMS to a single (cheaper) segment, the platform automatically cleans outbound text for standard SMS encoding: emojis are removed, and curly quotes, em-dashes, ellipses and similar characters are converted to plain equivalents. Characters outside the standard SMS set are dropped, so they won’t survive on SMS.
• Time your messages appropriately. Avoid sending messages outside business hours in the recipient’s timezone.
• Monitor delivery rates. If you notice poor delivery in certain regions, consider purchasing a local number for that country to improve trust and deliverability.
• Assign an AI Agent to respond to incoming messages quickly, especially outside business hours.