The WhatsApp messenger service will start charging businesses for sending marketing and customer service messages, it said on Wednesday.
The messages will be charged at a fixed rate for confirmed delivery, ranging from 0.5 cents to 9 cents per message depending on the country, WhatsApp said.
Facebook has been looking at ways to monetise its WhatsApp service in the face of rising costs as it spends heavily to improve privacy safeguards and tackles concerns about social media addiction.
WhatsApp, which has around 1.5-billion users, said starting Wednesday businesses can use its WhatsApp Business API to send notifications such as shipping confirmations, appointment reminders and event tickets.