The WhatsApp 24-Hour Customer Service Window
The 24-hour customer service window is the single most important concept in WhatsApp Business messaging. Knowing when it's open or closed determines whether you can send a free-form message or have to use a paid template. This guide explains it clearly with examples.
What is the 24-hour window?
The 24-hour window is a period of free, unrestricted messaging that opens whenever a customer sends you a WhatsApp message. During this window you can reply with anything — free-form text, images, videos, interactive buttons — without using a pre-approved template.
The clock resets every time the customer messages again. So a chatty customer keeps the window open indefinitely. A customer who replies once and goes quiet closes the window 24 hours after their last message.
How it works (timeline example)
Inside the window vs Outside
✅ Inside the 24-hour window
- Free-form text replies
- Images, videos, documents, audio
- Interactive buttons & list pickers
- Pre-approved templates also work (for follow-ups)
- First 1000 conversations/month are free; beyond that, charged at the Service rate
⛔ Outside the 24-hour window
- ❌ Free-form messages — blocked by Meta
- ✅ Pre-approved templates only
- The template's category (Marketing / Utility / Authentication) determines the conversation cost
- If the customer replies to your template, a new 24-hour window opens
Why this rule exists
WhatsApp's value to consumers is that it's a low-spam channel — you mostly get messages from people you know or businesses you've actively engaged with. The 24-hour window is Meta's mechanism to enforce this: businesses can only send unrestricted messages when the customer has invited the conversation. Outside that, every business-initiated message must use a template Meta has pre-approved as appropriate.
Best practices
- Reply fast. The longer you take, the higher the chance the window closes before you can follow up.
- Use templates strategically. A well-crafted template that prompts a reply opens a fresh 24-hour window.
- Don't assume the window is open after sending a template. The customer must message back to open it.
- Plan your conversation flow so the most important content is sent inside the window.
- Send transactional updates as Utility templates — they're cheap (~₹0.12) and Meta-approved without needing the window to be open.
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Frequently asked questions
What is the WhatsApp 24-hour window?
The 24-hour customer service window is a period of free, unrestricted messaging that opens whenever a customer sends a message to your WhatsApp Business account. During this window you can reply with free-form text, media, interactive messages — anything — without needing a pre-approved template. The window stays open as long as the customer keeps replying (each new customer message resets the 24-hour clock).
When does the 24-hour window open?
Every time a customer sends you any message — a reply to your template, a fresh chat from a click-to-WhatsApp ad, or a customer-initiated inquiry. The clock resets each time the customer messages again. As long as customers respond within 24 hours, the window stays open indefinitely.
What can I send during the 24-hour window?
Anything: free-form text, images, videos, documents, audio, interactive buttons, lists, location, contacts. No template approval needed. This is when you provide customer service, answer questions, or have natural conversations.
What happens after the 24-hour window closes?
You can no longer send free-form messages to that customer. To re-engage them, you must send a pre-approved template message — Marketing, Utility, or Authentication category. The customer receives the template, and if they reply, a new 24-hour window opens.
Is messaging in the 24-hour window free?
Mostly yes. The first 1000 service conversations per WhatsApp Business Account per month are free. Beyond 1000, service conversations are charged at a per-conversation rate (~₹0.30 in India). Compare that to template messages which always carry the per-conversation fee for their category.
Does sending a template open a 24-hour window?
Sending a template alone does NOT open the customer service window. The window opens only when the CUSTOMER messages back. If they reply to your template, a 24-hour window opens. If they read but don't reply, you still need templates for any further outreach.
Can I use the 24-hour window to send marketing?
Technically you can send any content during the window since templates aren't required. But Meta's anti-spam systems still apply — sending obvious marketing under the guise of a service reply will hurt your quality rating and may get you flagged. Use templates for marketing, even if you're inside a 24-hour window.
Use the 24-hour window to your advantage
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