The Messenger 24-hour window and message tags, explained
If you have read about Messenger automation, you have probably seen the "24-hour window" and "message tags". They are rules from Meta's Messenger Platform, the developer route that Page chat tools use: a business can reply freely for 24 hours after a person's last message, and after that only for a few narrow reasons. Spaces does not go through that platform. It connects your own Facebook account, so the tags do not apply, but the idea behind them still matters. This guide explains both, in plain English, and what they mean for a small business answering customers on Messenger.
Where the 24-hour window comes from
Meta lets businesses build chat tools for Facebook Pages through its Messenger Platform. Tools that use it agree to Meta's rules for automated messages, and the best-known rule is the standard messaging window.
In short: when a person messages a Page, the Page can reply as much as it likes for the next 24 hours. Each new message from the person starts the 24 hours again. Once the window closes, the Page can only send a message in a few specific situations, and it cannot send promotions.
The point of the rule is to stop people being chased by businesses they spoke to once. If you asked a shop about opening times last spring, you should not be getting their sale messages now.
What applies when you use your own account
Spaces connects Messenger by signing in to your own Facebook account through a secure link. It does not use the Messenger Platform, so there are no tags to attach, and nothing your agent sends is labelled as a Platform message. Read the box above on Meta's rules before you connect: automated use of your own account carries its own risks.
What does still apply is the behaviour Messenger watches for on any account. Messenger limits messages to people who have not replied, so a reply in a chat the customer started is normal use, and a message out of nowhere to someone who never wrote is not. Spaces keeps every Messenger account inside these limits:
| Action | Spaces limit per account |
|---|---|
| Messages | Up to 50 a day, at least 20 seconds apart |
| New conversations | 3 an hour, 8 a day |
New conversations also warm up for the first weeks after you connect or reconnect:
| Since connecting | New chats an hour | New chats a day |
|---|---|---|
| First 3 days | 1 | 2 |
| Rest of week 1 | 1 | 3 |
| Week 2 | 2 | 5 |
| Weeks 3 and 4 | 2 | 6 |
| After that | 3 | 8 |
This is published provider guidance, written in our own words and last updated on 28 Aug 2026. It is advice, not a promise from the platform, and the platform can change what it watches for at any time.
- Between 10 and 50 messages a day, and never more than 50.
- Start at about 15 a day and add about 5 a week.
- Message people you share mutual connections with.
The window as a good habit
Even without tags, the 24-hour idea is a useful rule of thumb. A conversation that is still warm is one where the customer expects to hear from you. A conversation that went quiet weeks ago is closer to a cold message, and should be treated that way.
In practice that means three things for a small business:
- Answer quickly while the customer is still around. An AI agent helps most here, because it can reply within minutes at any hour.
- Send updates that the customer would clearly want, such as an order or booking change, even if a few days have passed.
- Do not use old chats as a mailing list. Promotions to people who went quiet are the messages that get ignored, reported, and noticed.
Which late messages are fine
Here is how common situations look, side by side. The middle column is what a Messenger Platform tool would need to do. The right column is good practice when you answer from your own account.
| Situation | On the Messenger Platform | Good practice on your own account |
|---|---|---|
| A customer asked a question two days ago and nobody answered | Outside the window. A person might use the human agent tag if it is still allowed | Reply, apologise for the wait and answer the question. It is their conversation |
| An order the customer placed in the chat has shipped | A post-purchase update | Send a short update in the same chat |
| A booking made in the chat has moved | A confirmed event update | Tell them straight away and offer an alternative |
| You have a new offer and want to tell past customers | Not allowed with a tag | Do not send it in Messenger. Post it on your Page instead |
| A customer went quiet after you sent a quote a week ago | Outside the window, and no tag fits | One polite follow-up at most, then leave it |
| Someone liked your Page but never wrote | Not allowed | Do not message them |
An example of a late reply done well
A garden centre missed a message over a bank holiday weekend. Names and details are examples.
| Who | Message |
|---|---|
| Customer (Saturday) | Do you have any olive trees in stock? Looking for one about 1.5m |
| AI agent (Tuesday morning) | Hi Martin, sorry for the slow reply, we were closed for the bank holiday. Yes, we have three olive trees around 1.5m at the moment, from £89. Would you like me to put one aside while you decide? |
| Customer | Yes please, I can come Thursday |
| AI agent | Lovely, one is reserved under Martin until Thursday closing at 5pm. Just ask at the till. |
The reply was late, but it answered the exact question the customer asked, in the chat he started. That is very different from a message about a spring sale sent to everyone who ever wrote.
Why mass messages are refused
Some owners hope that answering from their own account is a way round the Platform's rules, so they can message every past customer. It is not, and Spaces does not allow it. The same cold message sent to many people. Spaces refuses copy-paste blasts. Any message to someone who said stop, unsubscribe or similar in that chat.
The daily limits are low on purpose. With 50 messages and 8 new chats a day, Messenger is for conversations, not campaigns. If you need to tell lots of people something, a Page post or a newsletter they signed up for is the right tool.
Notes to give your AI agent
Messenger timing rules:
- Reply to every customer message as soon as you can.
- If a reply is more than a day late, start with a short apology and answer the question.
- Send order or booking updates in the same chat when something changes.
- At most one follow-up on a quote, and only if the customer asked for one.
- Never send offers or news to past customers in Messenger.
- Never start a chat with someone who has not written to us unless I name them.
- If Spaces says to wait, wait.Common mistakes
- Thinking that an old chat gives you permission to send offers. It gives you a conversation, not a mailing list.
- Sending a "just checking in" message to every quiet chat at the end of the month.
- Letting the agent pretend to be a person to justify a late reply. Be honest about who is answering.
- Ignoring a late message because it feels awkward. A short apology and a real answer almost always lands well.
- Using several Facebook accounts to send more messages. Each account has its own limits, and working round them is ruled out by Spaces' Terms.
Who you message
In short
The 24-hour window and message tags are Messenger Platform rules for Page chat tools. Spaces connects your own Facebook account instead, so the tags do not apply, but the reason behind them does: answer people while the conversation is live, send updates they would want, and never treat old chats as a list to market to.
Do that, and Messenger's tight limits are rarely a problem, because almost everything your agent sends is a reply to someone who wrote first.
Pricing
FAQ
What is the Messenger 24-hour window?
It is a Messenger Platform rule: a Page can reply freely for 24 hours after a person's last message. After that, tools built on the Platform can only send messages for a few specific reasons, using message tags.
Does the 24-hour window apply to Spaces?
Not in the same way. Spaces connects your own Facebook account rather than using the Messenger Platform, so there are no tags to use. Messenger still limits messages to people who have not replied, and Spaces keeps every account inside its limits.
Can I reply to a customer after more than 24 hours?
Yes, in a chat they started. Apologise for the wait and answer their question. What to avoid is using old chats to send offers or news.
What is the human agent tag?
It is a Messenger Platform tag that gives a person on a business's team a little longer to answer a question that needed more time. It is only for people, not automated replies. Meta's developer documentation has the current details.
Can my AI agent send promotions to past Messenger customers?
No. The same cold message sent to many people. Spaces refuses copy-paste blasts. Post offers on your Page, where people who want them will see them.
Can my agent send order and booking updates?
Yes, in the chat where the order or booking was made. Short, useful updates that the customer would expect are good practice on any messaging app.
What happens if a customer tells us to stop?
The agent stops. Any message to someone who said stop, unsubscribe or similar in that chat.
Where can I check the current Platform rules?
Meta's developer documentation for the Messenger Platform lists the current window, tags and opt-in options. They change from time to time, so check there rather than relying on any guide.