Click to WhatsApp ad chats: how the free window works in 2026

The direct answer

A Click to WhatsApp ad chat starts when a person taps an ad on Facebook or Instagram and sends a first message through the WhatsApp app on Android or iOS. Your business then has 24 hours to reply. If you reply inside that time, Meta opens a free entry point window. During that window, every message you send to that person is free of Meta's per-message charge, including approved templates.

The length of that window has changed. For about two years Meta described it as 72 hours. Meta's WhatsApp Business Platform pricing documentation now says the window may remain open for up to 7 days when the chat started from a Click to WhatsApp ad. Meta recorded the change in its changelog entry dated 28 September 2026, and the rollout is gradual, so some chats still show 72 hours for a period. Chats that started from a Facebook Page call-to-action button keep the 72-hour length.

No statute or regulation sets this window. It is a billing benefit described in Meta's WhatsApp Business Platform pricing documentation, and it can change when Meta updates that documentation. Look for the current wording under WhatsApp Business Platform pricing on Meta for Developers before you build a campaign around any number, including the one in this guide.

The window is separate from the standard 24-hour customer service window. That standard window opens every time a customer messages your business, and it resets each time they write again. Inside it you can send ordinary typed replies. Once it closes, you can only send approved message templates until the customer writes again. The free entry point window changes the price of those messages. It does not change the rule about what you may send.

How the window is worked out, step by step

Most mistakes come from counting from the wrong moment. The clock that matters is the moment your reply goes out, not the moment the ad was clicked. Use this sequence with the timestamps from your inbox or messaging tool:

1. Record the time of the customer's first message. It has to come from a Click to WhatsApp ad, opened in the mobile app. Chats that started on WhatsApp Web or a desktop app do not qualify.
2. Count 24 hours from that message. Your first reply must be sent inside that count. A reply sent at hour 24 and one minute does not open the window.
3. Note the time of that reply. The free entry point window starts from your reply, not from the customer's message.
4. Add the window length to your reply time. For a Click to WhatsApp ad chat, add up to 7 days. For a Facebook Page button chat, or a chat still showing the older length during the rollout, add 72 hours.
5. Treat the result as the last moment messages are free. After that point, the normal rules return: free-form replies only within 24 hours of the customer's latest message, and approved templates at standard per-message rates otherwise.

You can use the free calculator on this page to run these five steps with your own timestamps. The calculator gives you the dates. It does not tell you the length Meta is applying to a specific chat, so check the chat's own billing line on your invoice when the dates matter.

A worked example

Take a hypothetical dental clinic in Lagos that runs a Facebook ad for teeth whitening. The example uses illustrative times and does not describe a real business.

On a Monday at 09:00, a patient taps the ad and writes: do you have Saturday slots? The first message opens a 24-hour customer service window that closes at 09:00 on Tuesday. A receptionist replies at 09:20 on Monday. That reply sits inside the 24 hours and opens the free entry point window. Under the current length, the window may stay open until 09:20 the following Monday. If the chat still shows the older length, the window ends at 09:20 on Thursday.

The clinic's messages then play out like this:

• Monday, 09:25: a free-form list of Saturday slots. This is allowed because the patient wrote less than 24 hours earlier.
• Tuesday, 10:00: a booking confirmation sent as an approved template. The patient's last message was more than 24 hours earlier, so only a template is allowed. Inside the free window, it is not charged.
• Thursday, 09:00: an appointment reminder template. Still inside the window, so free even on the shorter length.
• The following Monday, 08:00: a post-visit message template. Free under the current 7-day length, but outside a 72-hour window.
• The following Tuesday, 10:00: a follow-up template sent after the window has closed. This message is billed at the per-message rate for its template category in the recipient's country. The rate is listed on Meta's rate cards, and the clinic's messaging provider may show its own price. See the vendor's current pricing for the figure.

In this example, four messages are free because they fall inside the window. The fifth is charged only if it is sent after the window closes. The clinic's cost depends on how many follow-ups it schedules inside the window and how many patients it messages after it. The free calculator on this page lets you test your own timing before you commit to a schedule.

Cases that change the answer

The window is not the same for every chat. The entry point, the device, the reply time and the messaging tool all change the result. The table below shows the cases that most often change the answer. The rows reflect Meta's documentation as reported by independent guides in October 2026.

Caps and exclusions matter too. The free window does not cover the ad itself. Meta bills the ad spend to your ad account, so the window reduces messaging cost only. Outside the free window, the caps that apply are different. From 1 October 2026, each business phone number gets 1,000 free service messages a month, and Meta bills for service messages above that figure. Reactions remain free. Reported exemptions for eligible government and non-profit organisations run through 31 December 2027, so check whether your organisation qualifies before you assume the exemption applies.

Expiry is the other case that changes the answer. A window that was open when a campaign was planned may have closed by the time the follow-up goes out. Build the schedule from the reply timestamp, and set reminders for the last day the window is open.

Common mistakes

The most expensive mistake is a slow first reply. A team that answers after 24 hours never opens the free window, and every message after that is priced as ordinary template traffic. The fix is a fast first reply, even if it only confirms that someone will answer soon. A short automated acknowledgement sent inside the 24 hours also counts as the reply that opens the window.

The second mistake is hard-coding 72 hours into a follow-up schedule. Some teams planned sequences around three days and will miss value under the current length. Other teams planned around seven days, and a few chats will still close at 72 hours during the rollout. Build the schedule to finish inside the shorter length, then add optional messages that only run when the chat is still open.

A third mistake is assuming that every chat from a link is free. Only chats that start from a Click to WhatsApp ad or a Facebook Page button qualify. A chat that starts from a link on a website or a QR code is priced under the normal rules, even if the team expected the free window.

The last mistake is treating the free window as permission. The window changes the price, not the rules on what a business may send. Marketing messages still depend on the customer's consent and on the platform's messaging policies. Marketing templates also count toward Meta's per-user limits, so a long campaign can still be restricted even when every message is free.

What to check with your provider, your finance team or a lawyer

Start with the current wording on Meta's WhatsApp Business Platform pricing page, because the length of the window has changed within a single quarter. Ask your messaging provider which length it applies to each entry point, and whether it shows the free window on invoices. Ask your finance team to match one month of billing lines against the timestamps of ad chats. That check shows whether the free messages are being recorded as free.

Ask a lawyer about consent and data handling before you send marketing messages to people who came from an ad. Consent rules sit in your country's data protection law and in the platform's messaging terms, and the free window does not replace either. A lawyer can also tell you what records to keep to show consent if a customer complains.

Where AI workers fit into routine work

Employers that want less routine HR and payroll work on their staff often start with the repetitive parts: onboarding reminders, document chasers, payslip questions and monthly reports. An AI worker can run those steps on a schedule, record the timestamps and pass the exceptions to a person. The person still approves pay decisions and handles the cases that need judgement.