The policy wording is broad: a business must respect all requests, on or off WhatsApp, by a person to block, discontinue or otherwise opt out of communications, including removing that person from its contacts list. Privacy laws such as the GDPR add that withdrawing consent must be as easy as giving it.
In practice, businesses handle opt-outs with keyword detection (STOP, UNSUBSCRIBE and common variants), an explicit button in marketing templates, and a suppression list that removes the contact from future campaigns immediately. People can also stop marketing messages from a business, block it or report it from the chat itself.
A clean opt-out path protects deliverability. A customer who cannot find the exit blocks or reports the number instead, and that negative feedback lowers the quality rating of the number and of the template that was used.
In Kanal, opt-outs are handled automatically, so WhatsApp campaigns only reach Shopify customers who still want them.
