Updated September 2026 with Meta’s pricing rules in force, including the service message charges announced for October 1, 2026.
The WhatsApp service window is a 24-hour period that opens every time a customer sends a message to your business. Inside it, you reply freely. And it renews: each new customer message restarts the 24-hour countdown.
What about the famous 72 hours? They exist in one case only: when the conversation starts from a click-to-WhatsApp ad or from a button on a Facebook Page. That is the Free Entry Point, and inside it every message is free for 72 hours.
If you own a small or medium business (SMB) and use the official WhatsApp API, understanding this window is what separates free customer service from paid messaging. This guide explains both windows, what costs what, and what changes in October 2026.
complete guide to sales and customer service on WhatsApp
Quick summary
- The standard service window (CSW) lasts 24 hours and renews with each customer message.
- Inside the window, service messages (free-form text) are free until October 1, 2026.
- Utility templates are also free inside an open window.
- Marketing messages are always charged, even with the window open.
- The only 72-hour window is the Free Entry Point: a conversation started by a click-to-WhatsApp ad or a Page button. Inside it, every message is free.
- The FEP zeroes out the cost, not the permission: free-form text still requires the 24-hour window to be open. Customer silent for 24 hours? Templates only (free during the 72 hours).
- Outside the window, you can only send an approved template, and it is paid.
- Source: Meta’s official pricing documentation, August 2026.
What is the 24-hour service window?
The service window (Customer Service Window, or CSW) is the 24-hour period in which your business can reply to a customer with free-form messages. It opens the moment the customer sends any message to your official API number.
Inside that window, you do not need a pre-approved template. You can send text, audio, images or documents, in whatever format the conversation calls for. This is Meta making sure real customer service can flow.
Outside the window, the rule flips. With no recent message from the customer, the business can only start contact with a template approved by Meta, and that template is paid. We cover this further below.
Source: WhatsApp Business Platform pricing documentation, accessed in August 2026.
Does the window renew? Yes, with every customer message
Each new message from the customer restarts the 24-hour countdown. It is not a fixed limit per conversation, it is a sliding window.
A practical SMB example: a customer asks the price of a procedure at your clinic at 10 a.m. on Monday. The window is open until 10 a.m. on Tuesday. She replies at 8 p.m. with a new question. Done: the window now runs until 8 p.m. on Tuesday.
As long as the customer stays engaged in the conversation, the window stays open. In practice, active customer service rarely bumps into the limit. The problem shows up when the customer disappears and you need to resume contact later.
What is free and what is paid inside the window
Inside an open 24-hour window, today’s rule is this:
- Service messages (free-form text): free until October 1, 2026. These are the normal customer service replies, with no template.
- Utility templates: free. These are transactional templates, such as an order confirmation or a delivery notice, sent while the window is open.
- Marketing messages: always paid. A marketing template is charged even inside an open window. The window does not zero out the cost of promotion.
That last point catches a lot of people off guard. Having the window open does not mean “send promos for free”. Marketing charges are independent of the window.
WhatsApp marketing vs utility messages: what is the difference
Outside the window, no free-form messaging. Every business-initiated contact becomes a template, and a template outside the window is paid according to its category (marketing, utility or authentication).
how much the official WhatsApp API costs: table and examples
| Message type | Inside the 24-hour window | Outside the window |
|---|---|---|
| Service (free-form text) | Free until Oct 1, 2026 | Not allowed (template required) |
| Utility template | Free | Paid |
| Marketing template | Paid | Paid |
Source: Meta’s pricing documentation, Aug 2026.
The 72-hour ad window (Free Entry Point)
The only 72-hour window that exists on WhatsApp is the Free Entry Point (FEP). It applies when the conversation starts in two specific ways:
- The customer clicks a click-to-WhatsApp ad (the Facebook or Instagram ad that opens your WhatsApp directly).
- The customer taps the WhatsApp call-to-action button on a Facebook Page.
In those two cases, Meta opens a 72-hour window in which every message is free. Service, utility and even marketing: no message is charged inside those 72 hours (source: Meta’s pricing documentation, Aug 2026).
But pay attention: the two windows are independent and measure different things. The FEP defines the cost; the 24-hour window defines the permission to send free-form text. Inside the 72 hours, you can only send a free-form message while the 24-hour window is open. If the customer goes a day without replying, templates are what is left, and they stay free until the FEP ends. Each reply from the customer reopens 24 hours of free-form conversation. Meta’s documentation is literal: “if the customer service window closes, you will only be able to send template messages” (Meta’s pricing documentation, accessed in August 2026).
That is why paid traffic to WhatsApp became so strategic. Every ad click opens three days of conversation with no per-message cost. It is the most generous window on the platform, but it is only born from an ad or a Page button. There is no way to “extend” the standard 24-hour window to 72.
how to automate the post-click of click-to-WhatsApp ads
And when the window closes?
With the window closed, the business can only talk to the customer through an approved template, and every template outside the window is paid. There is no exception: with no recent message from the customer, there is no free sending.
The practical path has three steps:
- Pick the right category. Resuming a support conversation or notifying about an order is usually utility. An offer is marketing, and costs more.
- Send the template and wait for the reply. Any reply from the customer reopens the 24-hour window.
- With the window reopened, go back to normal service, with free-form messages again.
The everyday lesson: reply fast while the window is open. Every conversation resolved within the 24 hours is a paid template you do not have to send later. Automation helps exactly here, replying instantly, including in the middle of the night, and keeping the window alive while the customer engages.
What changes in October 2026
Starting October 1, 2026, Meta begins charging for service messages, the free-form ones inside the 24-hour window. Today they are free.
According to Meta’s official pricing updates page, accessed in August 2026:
- The service message rate will be equal to the utility rate in each market.
- The rates will be announced by September 1, 2026.
- Until September 30, 2026, service messages inside the window remain free.
What does not change: utility templates stay free inside an open window, marketing stays paid always, and the 72-hour Free Entry Point keeps every message free.
For an SMB, the customer service conversation stops being zero cost and starts carrying a value per delivered message. That makes it even more important to resolve support with fewer back-and-forths, and to make good use of the free 72 hours from ads.
Notice the contrast this change creates. The Free Entry Point keeps every message free after October 1, according to Meta’s non-template messages documentation (accessed in August 2026). While the ordinary conversation starts costing per message, the lead from a click-to-WhatsApp ad still gets free customer service for 72 hours. After the change, the ad becomes the lowest-cost entry door for customer service.
service message charges on WhatsApp: what changes and how to prepare
FAQ: frequently asked questions about the WhatsApp window
What is the 24-hour service window?
It is the period in which your business can reply to a customer with free-form messages on the official WhatsApp API. It opens when the customer sends a message and lasts 24 hours from their last message.
Does the 24-hour window renew?
Yes. Each new message from the customer restarts the countdown. As long as they keep replying, the window stays open.
How does the 72-hour window work?
It only exists in the Free Entry Point: a conversation started by a click-to-WhatsApp ad or by a WhatsApp button on a Facebook Page. During those 72 hours, every message is free, marketing included. The permission to send free-form text still follows the 24-hour window. Customer has not replied for a day? Send a template, free until the 72 hours end.
What is the Free Entry Point (FEP)?
It is the name Meta gives to the free entry point of a conversation. When the customer arrives through a click-to-WhatsApp ad or a Page button, a 72-hour window opens that zeroes out the cost of any message. Free-form conversation, however, still depends on the 24-hour window being open. Each customer reply renews those 24 hours.
Can I send a promotion inside the 24-hour window?
You can, but it is charged. A marketing template is paid even with the window open. The only exception is the 72-hour Free Entry Point window, where marketing is also free.
Can I reopen the window after it closes?
Yes, indirectly. You send a paid template and, if the customer replies, a new 24-hour window opens. There is no reopening without an action from the customer.
I missed the 24-hour deadline. Now what?
The only path is to send a template approved by Meta, which is paid. Once the customer replies, free-form conversation goes back to normal.
Which template should I use when the window closes?
It depends on the intent. To resume a support conversation or notify about an order, use utility, which costs less. For an offer, the template is marketing. Heads-up: a mixed template combining utility with promotion is categorized as marketing by Meta.
how much each template category costs in practice
Conclusion: master the window before it becomes a cost
The rule fits in three lines. The standard window is 24 hours and renews with every customer message. The free 72 hours only exist when the conversation is born from an ad or a Page button. And, starting in October 2026, even the service message will be charged.
Whoever replies fast makes the most of the window and pays for fewer templates. This is where AI automation makes the difference: NicoChat answers your customers instantly, 24/7, on WhatsApp and across the platform’s 18 channels, with handoff to your team when it matters.
Want to see it in practice? Start NicoChat’s 7-day free trial, no credit card, and let the service window work in your favor.
start with the complete guide to WhatsApp sales and customer service
