WhatsApp 24-Hour Window & Template Messages
Updated
Quick answer: On the WhatsApp Business API, when a customer messages you, a 24-hour customer service window opens. Inside that window you can send any free-form message, and those replies are free. Outside it — or to start a conversation — you must use a message template pre-approved by Meta, in the marketing, utility or authentication category, and Meta charges per delivered template.
When you can send any message, and when you need an approved template.
The 24-hour rule is the single most important concept in WhatsApp Business messaging. Here is how it works, how templates are categorised and approved, and how to write templates that get approved.
- Customer message → 24-hour window for free-form replies
- Outside the window: approved templates only
- Templates: marketing, utility or authentication
How the 24-hour window works
Every new message from the customer restarts the 24-hour timer. While it is open, your agents and chatbot can reply with text, images, documents, buttons or product lists without a template. Once 24 hours pass with no message from the customer, you can only reach them with an approved template. Conversations started from a Click-to-WhatsApp ad or a Facebook Page call-to-action get a longer, 72-hour free window.
Template categories
| Category | Use it for | Example |
|---|---|---|
| Marketing | Promotions, offers, announcements, re-engagement | "Diwali sale: 20% off everything this weekend" |
| Utility | Updates about something the customer did or requested | "Your order #1042 has shipped" |
| Authentication | One-time passwords | "Your login code is 482913" |
How to get templates approved
- Pick the correct category — Meta re-categorises promotional "utility" templates as marketing
- Do not start or end the message with a variable, and give sample values for every variable
- Avoid vague, threatening or misleading wording
- Keep the body under 1,024 characters; the footer under 60
- Use buttons (quick reply, URL, call) to make the next step obvious
Templates in Advertz
Create templates in Advertz, submit them to Meta, and see the approval status, quality rating and rejection reason in one place. Approved templates sync automatically, and Meta status updates arrive instantly by webhook.
Frequently asked questions
What happens after the 24-hour window closes?
You can no longer send free-form messages. To contact the customer again you must send an approved template, which Meta charges for.
How long does WhatsApp template approval take?
Often a few minutes, and up to 24 hours in some cases.
Are messages inside the 24-hour window free?
Yes. Free-form service replies within 24 hours of the customer's last message are not charged by Meta.