Connect WhatsApp via the official Twilio API or a personal number by QR.
Chatasist connects WhatsApp two ways. Choose based on whether you have an official WhatsApp Business API number (Twilio) or want to link a personal/business number directly.
Option A — Twilio (official API)#
Recommended for production. You supply your Twilio credentials when creating the channel:
| Field | Format |
|---|---|
| Account SID | Your Twilio account SID. |
| Auth token | Your Twilio auth token (stored encrypted). |
| WhatsApp sender number | Your Twilio WhatsApp number with its country code, e.g. +14155551234. Spaces, dashes, and the whatsapp: prefix are all accepted. |
| Message template Content SID | Optional. An approved template (HX…) used to reply outside the 24-hour window. |
All of these can be edited later. Leaving the auth token blank on an edit keeps the stored token; entering a value rotates it.
Webhooks#
Chatasist configures your sender's webhooks automatically when you save the channel. If it can't — Twilio sandbox numbers and senders owned by another Twilio project aren't reachable over the API — set them in the Twilio Console:
Inbound: https://api.chatasist.com/webhooks/whatsapp/twilio
Status: https://api.chatasist.com/webhooks/whatsapp/twilio/status
Every request is verified against the X-Twilio-Signature header using your auth token;
requests that fail validation are rejected with 403.
Attachments#
Photos, voice notes, videos, and documents are carried in both directions, up to WhatsApp's limits (16 MB inbound; 5 MB for outbound images, 20 MB for other outbound media). If an attachment can't be retrieved, the message still appears in the conversation marked as an image, voice note, or file, so nothing is silently dropped.
Delivery status#
Each outbound reply shows its state under the message — sending, sent, delivered, or read — updated live from Twilio's status callbacks. A reply WhatsApp rejected is marked not delivered and a note in the thread explains why.
The 24-hour window#
WhatsApp allows free-form business replies only within 24 hours of the customer's last message. Outside that window, Chatasist sends your configured template instead; without one, the reply is not delivered and is flagged in the conversation. See How to connect WhatsApp for setting a template up.
Option B — Personal number by QR#
Links a personal or business number by scanning a QR code, similar to WhatsApp Web.
The QR connection has a hard scaling limit, and inbound media is capped at 64 MB. Use Twilio for high volume.
- Connecting and reconnecting are handled for you.
- If the connection drops, Chatasist emails workspace Administrators an alert (after a short delay, throttled).
- Inbound messages reach Chatasist over an authenticated webhook.
The in-dashboard live QR pairing UI is coming soon — the current build surfaces connection status read-only while that experience ships. Until then, Chatasist handles pairing for you.
How WhatsApp customers are named#
A customer who writes to you on WhatsApp appears in the inbox under their phone number
(for example +994501234567), and the number is saved in their customer profile. You can
find them by searching for the number, typed any way: with or without +, spaces or dashes.
If you rename the customer, the number stays in their profile.
Some people write from a WhatsApp username instead, which hides their number from businesses. WhatsApp never shares that number, so these customers appear as WhatsApp user #004512, after the number of their first conversation with you. The name stays the same in later conversations, so you can still tell them apart and find them.
Send single WhatsApp messages or broadcasts to many contacts.