This is WhatsApp’s rule, not ours, and it catches everybody out once. Worth five minutes now rather than confusion later.
What the rule is
When a customer messages you, WhatsApp opens a 24-hour window. Inside it you can reply normally, as many times as you like, saying whatever you need to say.
Once 24 hours pass with no message from them, WhatsApp will only let you send an approved template until they reply again. Files cannot be sent at all until the window reopens.
Why it exists
To stop businesses messaging people who are not expecting it. Every business on WhatsApp lives with it, not just ones using this add-on and not just small ones. You cannot turn it off and neither can we.
It is worth understanding rather than resenting. It is the reason WhatsApp is still a channel customers actually read, rather than another inbox full of things they ignore.
How to tell which state you are in
A line just above the reply tools says:
- “You can reply for 5 more hours”, counting down (in minutes for the last hour). Send whatever you like.
- “Over 24 hours since they last messaged. Start with a template”. The window has closed. Send a template, or wait for them to reply. Someone who has never messaged you gets “They haven’t messaged you yet” instead.
When the window has closed there’s a Choose a template button beside that line. Press it to open your approved templates, fill in anything the template asks for, and press Send template. Hide puts it away again so you can read the conversation.
The countdown is there so you can make a judgement call. If it says two hours left and you know you will need to send something tonight, send it now.
The way round it
If you connected using the “keep my app” route, replying from the WhatsApp Business app on your phone is not subject to the window, and Meta does not charge for it either.
So: window closed, and you genuinely need to reach that customer? Answer from the app on your phone. It appears in ServiceM8 afterwards like any other message.
What a reply costs
Replies inside the window are free for the first 1,000 each month, per WhatsApp number. Meta has charged from the 1,001st since 1 October 2026, at the same rate as a utility template. Templates are charged whether the window is open or not. Replies sent from the app on your phone are not charged. What it costs has the detail.