The WhatsApp 24-Hour Window: When You Can Reply Freely and When You Need a Template

A customer wrote to you on Tuesday, and by Thursday WhatsApp will not let you answer with a normal message. That is the 24-hour window. When a customer messages your business, a 24-hour timer starts. While it runs, you can reply with anything. When it ends, you can only send a message template approved by Meta, and only to people who agreed to hear from you.

This article covers WhatsApp only. Meta is the company that owns WhatsApp, Instagram and Messenger.

How does the 24-hour window work?

Meta's documentation says the timer starts with a customer's message and resets to 24 hours every time the customer writes or calls again.

A flower shop gets this message on Tuesday at 3 p.m.: "Do you have red roses for Saturday?" The window is open until Wednesday at 3 p.m. The shop can send text, photos, a voice note or a payment link. If the customer answers on Wednesday at 10 a.m., the window now runs until Thursday at 10 a.m.

Only the customer's messages reset the timer. Your replies do not. If the customer goes quiet, the window closes 24 hours after their last message.

What can you send when the window is closed?

Only template messages. A template is a message you write in advance, with blanks for the name or the date, and that Meta reviews before you can use it. Templates come in three categories: marketing, utility and authentication.

You also need the customer's permission. WhatsApp's business policy says you must have opt-in permission from the person before you message them. Opt-in simply means the customer said yes to receiving your messages.

If the customer replies to your template, a new 24-hour window opens and the conversation goes back to normal.

Does Meta charge for messages inside the window?

Since July 1, 2025, Meta charges per delivered message instead of per conversation. It charges only for messages the business sends. Messages from customers to the business are not charged.

Since October 1, 2026, free-form replies sent inside the window are also charged, after the first 1,000 per business phone number each month. That free allowance resets every month and does not roll over. Template messages are charged by category and by the customer's country. Meta publishes the rates on its pricing page, and they change by country.

This describes the WhatsApp Business Platform, the connection Meta offers to software. The charges are Meta's, not those of any tool you use.

How do you work with the window every day?

  1. Answer while it is open. A bakery that answers "How much is the tres leches cake?" in ten minutes is still inside the window. The same answer two days later may need a template.
  2. Write down when each window closes. If you tell a customer "I'll confirm stock and write back this afternoon", your follow-up has to go out before their timer ends.
  3. Ask for permission early. "Do you want a WhatsApp reminder before your appointment?" A yes at booking time lets you message that person later with a template.
  4. Prepare templates before you need them. Meta says a review can take up to 24 hours. Do not submit the reminder the morning you need it.
  5. Write templates that invite a reply. "Your order is ready. Delivery or pickup?" gets an answer. An answer reopens the window.

Frequently asked questions

Can I send a free-form message after 24 hours? No. After the window closes, WhatsApp only delivers template messages to that customer, until they write to you again.

Does my reply reopen the window? No. Only a new message or call from the customer does.

Do these rules apply to Instagram and Messenger? Each channel has its own rules. This article describes WhatsApp only.

Where Simplixity Chat fits

Simplixity Chat puts WhatsApp, Instagram, Messenger, email and the chat on your website in one inbox, with a filter by channel and the full history of each customer. Its assistant answers with the information your business gives it and hands the conversation to a person when the customer asks or a keyword appears. For WhatsApp, it also sends campaigns with templates, and customers can opt out by writing BAJA or STOP. Simplixity Chat is not open to the public yet.

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