Why some WhatsApp tools can reply instantly but can’t message your customers out of the blue — and why that’s a good thing.
13 October 2026 · 6 min read · Updated 13/10/2026
If you’ve looked into invoicing on WhatsApp, you’ll have seen “the 24-hour rule” mentioned. It’s a Meta rule for businesses using WhatsApp’s business platform, and once you know what it covers it’s simple.
From Meta’s developer documentation (checked 13/10/2026): when a customer messages or calls a business, a 24-hour customer service window starts. While it’s open, the business can send any normal message. When it closes, the business can only send template messages — set wording that Meta has approved in advance. If the customer messages again before the 24 hours are up, the timer starts again from that moment.
It applies to the WhatsApp Business Platform (often called the API): the system that chatbots, booking systems and tools like GraftG are built on. It does not apply to you messaging customers yourself, from ordinary WhatsApp or the free WhatsApp Business app on your phone — you can message your customers whenever you like, within normal good manners and data-protection rules.
A bot like GraftG talks to you, not your customers. You message it the job; it replies with the PDF inside your own 24-hour window. That’s why it can answer instantly at any time of day.
What a bot can’t sensibly do is message your customer out of the blue with an invoice: it would need an approved template, and the invoice would arrive from a number your customer has never seen. So GraftG sends the PDF to you, and you forward it from your own WhatsApp. It reaches the customer from the person who did the job, in the chat they already have with you — which is also how it gets read and paid.
Since 01/07/2025 Meta charges businesses per message on the platform rather than per conversation; ordinary replies inside an open window are free, and so are utility templates sent inside an open window. You don’t pay Meta anything to message your own customers from your phone. If a tool you’re considering messages customers for you, it’s worth asking how those messages are sent and who pays for them.
Nothing, directly — but the idea behind it is a good habit. Customers expect a quick reply on WhatsApp, and an enquiry answered within the hour is far more likely to become a job than one answered tomorrow. If you can’t reply on the tools, the free WhatsApp Business app can send an away message and has quick replies for the questions you get every day (“How soon can you come out?”, “Do you do free quotes?”).
If a customer messages you a week later about a quote, you can simply reply — there’s no window on your own phone. And if you use a bot for your paperwork, message it whenever suits you: each message you send opens a fresh 24 hours for its replies.
Because a bot shouldn’t cold-message your customers on WhatsApp, payment reminders are usually better by email. GraftG Pro’s late-payment reminders are emails sent in your name at 1, 7, 14 and 21 days overdue, and stop when the invoice is marked paid. See chasing late payments politely.
On the WhatsApp Business Platform, a 24-hour customer service window opens each time a customer messages a business. Inside it the business can send normal replies; after it closes it can only send pre-approved template messages until the customer messages again, which restarts the 24 hours.
No. The rule is for the WhatsApp Business Platform (the API used by bots and business software). Messaging your customers yourself from WhatsApp or the WhatsApp Business app on your phone isn’t limited by it.
Only with approved template messages if the customer hasn’t messaged that number in the last 24 hours, and it would arrive from a number they don’t know. GraftG sends the PDF to you instead, so you forward it from your own WhatsApp.
24 hours from the customer’s last message or call. Each new message from the customer restarts the 24 hours.
Not when you message them yourself from WhatsApp or the WhatsApp Business app. Meta’s per-message charges apply to businesses sending messages through the WhatsApp Business Platform.
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