The WhatsApp 24-hour window, explained
If you have read about WhatsApp for business, you have probably met "the 24-hour window". It is a real rule, but it only applies to one way of using WhatsApp. Here is what it is and when it matters.
In one sentence
On the WhatsApp Business Platform, a business can send free-form replies for 24 hours after a customer's last message; after that, it can only send pre-approved template messages until the customer writes again.
In more detail
The window opens when a customer messages the business and resets with every new message from them. Inside it, the business can reply with any normal message.
Once 24 hours pass with no message from the customer, the business can only start the conversation again with a template that Meta has approved, and templates are usually charged per message.
This rule belongs to the WhatsApp Business Platform, the system larger companies use through providers. It does not work the same way on the WhatsApp or WhatsApp Business app on your phone.
The idea behind the rule is simple. A customer who has just written to you is expecting an answer, so the business can reply freely. A customer who went quiet days ago did not ask to hear from you today, so the business has to use a message that was checked in advance.
You will mostly hear about the window from companies that sell access to the Business Platform, because it shapes how their customers plan reminders, follow-ups and support. If you run WhatsApp from the app on your phone, much of that advice is about a system you are not using.
A worked timeline
Here is how the window works for a furniture shop on the Business Platform. Names, times and products are examples.
| When | What happens |
|---|---|
| Monday 10:00 | A customer messages to ask about a sofa. The window opens and runs to Tuesday 10:00. |
| Monday 10:05 | The shop replies with prices and photos. Any normal message is fine. |
| Monday 18:30 | The customer asks about delivery. The window resets and now runs to Tuesday 18:30. |
| Tuesday 09:00 | The shop sends delivery dates. This is still inside the window. |
| Wednesday 12:00 | The shop wants to ask whether the customer has decided. The window closed on Tuesday evening, so only an approved template can be sent. |
| Wednesday 15:00 | The customer replies to the template. A new window opens, and normal replies are possible again. |
Notice that the shop's own messages never reset the window. Only a message from the customer does.
Two ways a business uses WhatsApp
| WhatsApp Business Platform | Your own account (the app, or the app plus Spaces) | |
|---|---|---|
| Who it tends to suit | Larger companies sending at volume, usually through a provider | Small businesses answering customers from the number they already use |
| How you connect | Through a provider set up with Meta | The app on your phone, plus a QR code to link Spaces |
| The 24-hour window | Applies | Does not apply |
| Templates | Needed outside the window, and usually charged per message | Not used |
| Sending to large lists | What it is designed for | Not what it is for, and Spaces refuses copy-paste blasts |
| Main rules to watch | The window, template approval and the platform's policies | WhatsApp's terms on bulk, automated and non-personal messaging |
If you use the Business Platform
- Reply quickly while the window is open, so you can answer fully without a template.
- End useful conversations with a question, because a reply from the customer reopens the window.
- Get templates approved before you need them, for things like appointment reminders and order updates.
- Keep templates short and relevant, and only send them to people who expect to hear from you.
- Plan for the cost of templates when you work out what WhatsApp costs you each month.
If you use your own account
On your own account there is no window and there are no templates, but that does not mean anything goes. WhatsApp's terms on bulk and automated messaging still apply, and accounts that message many people who did not expect it are the ones that get restricted.
- Reply as quickly as you like to anyone who messages you, whenever they wrote.
- Follow up with people who know you and expect it, such as a booking reminder or an update on their order.
- Stop as soon as someone says stop, and do not message them again.
- Keep new conversations few, especially on a number you have only just connected.
- Avoid sending the same text to many people at once.
These are the limits Spaces keeps on every connected WhatsApp number:
| WhatsApp limit in Spaces | Per connected number |
|---|---|
| Gap between messages | 15 seconds |
| Messages a day | 200 |
| New chats | 5 an hour and 10 a day, after warm-up |
| Warm-up: first 24 hours | No new chats yet |
| Warm-up: rest of week 1 | Up to 3 new chats a day |
| Warm-up: week 2 | Up to 6 new chats a day |
| Warm-up: weeks 3 and 4 | Up to 8 new chats a day |
Example: a follow-up a few days later
A kitchen fitter answers a quote request on their own WhatsApp number, through an AI agent connected with Spaces. Names and details are examples.
| Who | Message |
|---|---|
| Customer (Day 1) | Hi, can you quote for fitting a kitchen? Units are already bought. |
| AI agent (Day 1) | Hi Priya, thanks for getting in touch. Could you send a photo of the room and roughly how many units there are? Then I can get you a quote today. |
| Customer (Day 1) | Photo attached, 12 units. |
| AI agent (Day 1) | Thank you. For 12 units the fitting is usually two days. The full quote is in the attached document. Any questions, just ask here. |
| AI agent (Day 4) | Hi Priya, just checking the quote arrived safely. Happy to answer anything, and no rush at all. |
| Customer (Day 4) | Yes thanks, could you do the 14th? |
On the Business Platform, the Day 4 message would have needed an approved template, because three days had passed. On the fitter's own account it is a normal message in an existing chat. Priya asked for the quote and expects a follow-up, which is exactly the kind of message that is fine to send.
Common misunderstandings
- "The window applies to every WhatsApp account." It does not. It is a rule of the Business Platform.
- "After the window closes, you can never contact the customer." On the Business Platform you can, with an approved template.
- "My reply resets the window." Only a message from the customer resets it.
- "No window means no rules." On your own account, WhatsApp's terms on bulk and automated messaging still apply, and they are what lead to restrictions.
Which applies to you? A quick check
| If this is you | Then |
|---|---|
| You use the WhatsApp or WhatsApp Business app on your phone | You are on your own account. The window does not apply. |
| You linked WhatsApp to Spaces by scanning a QR code | You are still on your own account. The window does not apply. |
| You pay a provider for template messages | You are on the Business Platform. The window applies. |
| You want to send one message to thousands of people | That is what the Business Platform is for, and Spaces is not the right tool. |
Why it matters for your business
- If you use the Business Platform, plan replies inside the window, and get templates approved for reminders.
- If you use your own account in the app, the window does not apply, but WhatsApp's terms on bulk and automated messaging still do.
- Either way, messaging people who did not contact you is what gets numbers restricted.
- Knowing which system you are on stops you following advice that was written for the other one.
How Spaces handles it
Spaces connects your own WhatsApp account by scanning a QR code, not through the Business Platform, so there are no templates or window. Instead, Spaces paces every message and holds new chats to low daily limits, and replies to people who message you are never held back.
Every WhatsApp message through Spaces waits at least 15 seconds after the last one from the same number. If someone says stop, later messages in that chat are refused, and the same cold text cannot be sent to many people. These rules lower the risk to your number, but WhatsApp still decides what happens to accounts on its service, so read the note at the top of this page before you connect.
In short
The 24-hour window is a Business Platform rule: free replies for a day after the customer's last message, templates after that. If you run WhatsApp from your own account, it does not apply, but WhatsApp's terms on bulk and automated messaging do.
For most small businesses answering their own customers, the practical rule is simpler: reply to everyone who writes, follow up only with people who expect it and stop when asked. The WhatsApp limits page shows exactly how Spaces paces your number.
FAQ
Does the 24-hour window apply to the WhatsApp Business app?
No. It is a rule of the WhatsApp Business Platform. The app has its own limits and terms.
What is a template message?
A pre-written message approved by Meta that Business Platform users must use outside the window. Templates are usually charged per message.
Can I message customers after 24 hours with Spaces?
Yes, on your own account, within Spaces' limits and WhatsApp's terms. Keep it to people who know you and expect to hear from you, such as someone waiting for a quote or a booking reminder.
Does my own reply reset the window?
No. On the Business Platform, only a new message from the customer resets it. Ending a reply with a question is a common way to invite one.
Can Spaces send WhatsApp templates?
No. Spaces connects your own account with a QR code, which does not use templates. If you need templates and large broadcasts, the Business Platform through a provider is the better fit.
Is the Business Platform better than using my own account?
It depends on the job. For sending to large lists, it is the system built for that. For answering your own customers from the number they already know, your own account is simpler, as long as you respect WhatsApp's terms.
What happens if I message lots of people on my own account?
That is the behaviour most likely to get a number restricted. Spaces holds new chats to low daily limits and refuses the same cold text sent to many people, but it cannot remove the risk entirely.