Customer service window

The period after a customer messages a business during which the business may reply freely, without a pre-approved message-template. On WhatsApp it runs 24 hours from the customer's message, and it is the hinge the whole channel turns on.

Why it matters twice

As a permission rule. Inside the window a business sends free-form content; outside it, only an approved template. The window is what converts WhatsApp from a broadcast channel into a reply channel.

As a price. Under per-message-pricing, non-template messages inside an open window are free, and even utility templates are free inside it — while the same utility template outside costs whatsapp-pricing-docs. The customer's action is what makes the conversation cheap.

The free entry point variant

A 72-hour window, wider than the standard 24, opens when a business responds within 24 hours to a customer who arrived through a Click-to-WhatsApp ad or a Facebook Page call-to-action. Everything in it is free, template or not whatsapp-pricing-docs.

The design it implies

Every incentive points the same way: get the customer to speak first, then answer fast. A business that runs the channel well converts business-initiated (billable) contact into customer-initiated (free) conversation, which is precisely the behaviour meta wants on a platform whose users would otherwise be marketed at. The friction is productive thesis in synthesis is at its clearest here.

Cross-channel

No equivalent window is sourced for rcs-business-messaging or apple-messages-for-business — though Apple's model, where the brand largely cannot initiate and entry points are Apple's to grant apple-messages-for-business-docs, reaches a similar end by a different mechanism. Worth testing when a source on either channel's conversation rules arrives.

WeChat's version: longer, and capped (2026-09-22)

WeChat runs the same idea with different numbers. A user's message opens 48 hours for customer service replies, but only five of them; following the account, scanning a QR code or clicking certain menus opens three replies for one minute; a completed payment opens unlimited replies for 48 hours. The window is twice WhatsApp's in time and much narrower in volume.

per-message-pricing · message-template · whatsapp-pricing-docs · whatsapp-business-platform · wechat-official-account-messaging · synthesis