How the window works
- It opens when a customer sends you a message or calls you on WhatsApp.
- Each new message or call from them restarts the 24 hours.
- While it's open, you can send any kind of message: text, images, audio, documents, buttons, lists and reactions.
- After it closes, you can only send pre-approved template messages, and only to people who agreed to hear from you.
| Within 24 hours | After 24 hours | |
|---|---|---|
| Free-text replies | Yes | No |
| Photos, files, buttons and lists | Yes | No |
| Approved template messages | Yes | Yes, to people who opted in |
The clock follows the customer, not you: your own messages don't restart it. Meta: customer service windows
What happens if you reply after 24 hours
Meta refuses the message with error 131047, which it describes as “More than 24 hours have passed since the recipient last replied to the sender number”. Its fix is to send a template message instead. Meta: error codes
In HeyKiko, a reply from the shared inbox is checked before it goes. If the window has closed, it isn't sent, you're told why, and nothing appears in the chat history that the customer never received.
Templates: how to reach someone again
A template is a message you write in advance and Meta reviews, usually within 24 hours. Each one is marketing, utility (an update about something the customer did, such as a booking or an order) or authentication (a one-time code). You can add the customer's name or other details to it when you send it. Meta: message templates
When the customer replies to your template, a new 24-hour window opens, and you, or your AI agent, can talk freely again.
In HeyKiko, you write templates under Campaigns › Templates and submit them to Meta from there. You send one as a campaign, to a single contact or to a list, and any reply goes straight back to your agent.
What the window costs in 2026
- Replies inside the window are service messages. They were free until 30 September 2026. Since 1 October 2026, each number gets 1,000 free a month, and Meta charges from the 1,001st.
- Utility templates sent while the window is open were free from 1 July 2025, and have been charged since 1 October 2026.
- Templates sent after the window closes are charged by category and by the customer's country.
- When a customer messages you from a Click to WhatsApp ad, a free entry point window opens for up to 7 days, and Meta doesn't charge for messages in it.
- Meta warns that without a payment method on your WhatsApp account, service messages may stop being delivered once they're chargeable.
To see what this means for your own volumes, use the free WhatsApp API cost calculator. Meta: pricing
How an AI agent works with the window
An AI agent answers within seconds, so its replies always land inside the window. The window matters when a person takes over, and when you need to tell a customer something later.
- When a chat is handed to your team, someone has to reply within 24 hours of the customer's last message. In HeyKiko you can get an alert when nobody has replied after a number of minutes you choose.
- When you confirm, move or cancel a booking, HeyKiko tells the customer in their chat. If the window has closed, the change is still saved, and you're told the customer couldn't be messaged.
- The same rule applies to your own staff. To get alerts on WhatsApp, a team member sends “Alerts on” to your business number, which opens a window for them for 24 hours.
Tips for working with the window
- Answer fast. An AI agent does it for you, and alerts make sure a person follows up the same day.
- For anything that takes days, such as a refund or a repair, get the customer's email or open a case, so you can update them without waiting for them to write.
- Use utility templates for updates customers expect, like a booking reminder or an order that's ready, and marketing templates only for people who opted in.
- Don't send the same marketing template again and again. Meta may hold back marketing messages to keep engagement healthy, and low-quality messages lower your messaging limits.
Sources
Checked on 5 November 2026. We make HeyKiko, which this guide uses as its example; Meta’s rules apply to every tool.
