What is WhatsApp's 24-hour window?

The rule, in one sentence

You can reply freely, but you can't start freely.

Every message a customer sends you opens or resets a 24-hour window. Inside that window you send text, images, voice notes, whatever you want, with nobody's approval. Once the window closes — or when you want to write first — WhatsApp only lets you send a template approved by Meta.

Why it exists

So the platform doesn't fill with messages nobody asked for. It is the reason WhatsApp still has extraordinary read rates, and it is also why no provider can skip it, whatever they charge. If someone offers you "message anyone whenever you want", they're either selling you templates without saying so, or they're going to get your number banned.

What confuses people most

• The CUSTOMER opens the window, not you. Replying doesn't extend it: only their next message resets it.
• It's per contact, not per number: you have a separate window open with each person.
• A template does not open a window by itself. It opens the conversation; the free-reply window opens when the person answers.
• There's a 72-hour window, more generous and free, when the conversation starts from a click-to-WhatsApp ad or a Facebook/Instagram button.

⚠ What changed on 1 October 2026

The window did NOT go away. It still exists, it still opens and resets the same way, and it still governs whether you can send free-form text. What changed is that those messages stopped being free: Meta charges per message, at the same rate as utility templates in each market. On the same date it also started charging for utility templates sent inside an open window.

The 72-hour window from click-to-WhatsApp ads stays free.

Verified against Meta's documentation on 4 September 2026.

How to live with it in practice

• If your case is replying (support, enquiries, inbound sales), you live inside the window and may never need a template.
• If you need to notify something (an appointment, a shipment, an invoice), prepare the template before you need it. They're approved in minutes, but not at 3am on the day you need it.
• Store the timestamp of each contact's last message. It's one field in your database and it avoids 90% of rejections: if more than 24 hours have passed, send a template instead of attempting free text.

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