This is the rule that quietly invalidates support plans. Teams design their WhatsApp workflow around how they already work – triage today, follow up tomorrow, escalate to the specialist on Monday – and then discover that WhatsApp does not let them send the follow-up.
It is not a bug or a limit you can raise. It is the central mechanic of the platform, and it is worth understanding before you promise anyone a response time.
The rule
When a customer messages you, you may reply with anything you like for the next 24 hours. Free text, images, documents, whatever the conversation needs.
Once those 24 hours are up, you may no longer send free-form text to that person. You may only send a template – a message Meta approved in advance. If you want to say something that is not in an approved template, you cannot say it at all until they message you again.
Three details that matter more than they look:
- It is per customer. Every conversation has its own clock. There is no account-wide window.
- Only the customer resets it. Your replies do not extend it. An agent sending five messages buys no extra time.
- A template reopens nothing by itself. Sending one outside the window is allowed, but free-form messaging comes back only when the customer replies.
That last point is the useful one: an approved template is how you prompt a customer into reopening the conversation. It is the only door you control.
What this breaks in practice
Anything that waits over a weekend
A message arriving Friday evening and answered Monday morning is outside the window. The agent writes a careful reply, and it will not go.
This is the single most common way teams meet the rule – not through a design decision, but through an agent staring at a message that refuses to send.
“We’ll look into it and get back to you”
Any process where the answer takes longer than a day – a refund investigation, a parts order, a quote that needs a manager – ends with the resolution landing outside the window.
You can still deliver it, but only shaped as a template you wrote and submitted weeks earlier, with the specifics dropped into variables. Which means you have to anticipate the message before you need it.
Escalation between teams
First-line triages, passes to a specialist, specialist picks it up next shift. Common, sensible, and it spends the window on the handover.
Reopening something closed
Following up a week later to check the fix held, or chasing an unanswered question, both need a template. There is no “just send a quick message”.
What your helpdesk does about it
Whatever tool your agents work in – Chatwoot or anything else – the window is enforced by Meta, not by the tool. The send is simply refused at the API.
How that surfaces varies by tool and version: some warn the agent before they type, some let the message fail and show an error afterwards. Find out which yours does before go-live, because the bad version of this is an agent believing they answered a customer who never heard from them.
Worth testing deliberately during setup: let a test conversation go cold for a day, then try to reply, and watch exactly what the agent sees.
Designing around it
1. Answer inside the window
Obvious, and still the main answer. The window is generous for anything resembling real-time support. Most window problems are staffing problems wearing a technical costume – nobody on Saturday, or a queue nobody owns overnight.
2. Write your reopening templates in advance
You need a small library ready before launch, not when you first need one. At minimum: an update on an open case, a resolution notice, and a nudge for information you are waiting on.
Write them to invite a reply, because the reply is what restores free-form messaging. Approval takes time and rejection is common, so budget for revisions – see why templates keep getting rejected.
3. Tell customers when you are there
Set business hours and an away message so a Friday-night sender knows Monday is the answer. Expectation management costs nothing and prevents the complaint that the channel is unresponsive.
4. Let the customer open the conversation
Inbound-first flows – a WhatsApp button on your site, a click-to-chat link, a QR code – start the window and handle consent in the same action. This is also the cleanest form of opt-in, covered in collecting WhatsApp opt-in.
5. Do not promise an SLA the channel cannot keep
If you are putting WhatsApp in a client contract, the response commitment has to fit inside 24 hours or the contract has to say what happens when it does not. Working this out afterwards is how a technical rule becomes a commercial problem.
The useful way to think about it
WhatsApp is built for conversations, not for a ticket queue you work through at your own pace. The window is Meta encoding that: while the customer is engaged you can talk freely, and once they have moved on you need their permission again.
Teams that fight it end up with elaborate template libraries standing in for ordinary conversation. Teams that accept it staff for same-day replies, keep a handful of good reopening templates, and find the rule barely comes up.
Meta’s messaging rules and pricing change over time, and the window interacts with how conversations are charged. Check Meta’s current documentation before building around any specific figure.