Opt-in rules, message templates, the 24-hour window, and what gets your number blocked.
CTFM Team
WhatsApp is the highest-intent messaging channel most businesses can access, and the least forgiving. You are in someone's personal inbox, next to messages from their family. The tolerance for marketing there is close to zero.
Used well, it is excellent for anything urgent or tied to an order, like a delivery update or a booking reminder. Used as a broadcast channel, it gets your number blocked.
A free app you install on a phone. Manual conversations, a catalogue, quick replies, labels. Built for a small business answering messages by hand. No automation at scale, no integration with your other systems.
WhatsApp Business Platform
The API version. Send at scale, connect to your CRM, trigger messages from events like an order shipping. Requires approval, has usage costs, and enforces strict rules on what you can send.
If you are answering a few dozen messages a day yourself, the free app is genuinely all you need. The Platform is for when messages need to fire automatically from another system.
Check pricing at the source, always
Meta has restructured WhatsApp pricing more than once, including changing the unit it charges by. Any article quoting specific rates, including this one if it ages, may be wrong. Get current pricing from Meta's own developer documentation before you build a business case, and note the date you checked.
You must have permission to message someone, and the permission has to be genuine and specific.
That means a customer actively agreeing to receive WhatsApp messages from you, with a clear idea of what they will get. It does not mean:
Having someone's number because they bought something
Having a number from a lead list
Someone messaging you once about something else
A pre-ticked box buried in a signup flow
Get this wrong and you will be blocked fast. Enforcement runs on user reports. People report surprise marketing messages very readily.
Ask explicitly, at a moment when it makes sense
At checkout, so they can get delivery updates. During booking, so they get a reminder. Permission is easiest to get at the moment when the benefit is obvious to them.
Say what they will receive
"Order updates on WhatsApp" is specific. "Marketing messages" is vague and will surprise people later.
Record when and how they agreed
You may need to show it. Keep the timestamp and the wording they saw.
Make opting out obvious and instant
Honour it immediately. Someone who cannot leave will report you instead, which is far more damaging.
This is the mechanic that shapes everything about how the channel works.
If a customer messages you, you can reply freely in a normal conversation for a limited period, generally described as a 24-hour window. Outside that window, you cannot just send whatever you like. You have to use a pre-approved message template.
The customer contacted you. You are having a conversation. You can send normal, free-form replies, including answering questions and sending information.
This is where support happens.
So the channel is built to reward messages people expect and want. It is built to punish mass campaign blasts. That is on purpose.
Four use cases carry almost all of the value, and they share a quality: the customer would have wanted to know.
Order and delivery updates
Genuinely wanted, opened immediately, and reduces support enquiries. The strongest use case on this list.
Appointment reminders
Reduces no-shows for anything booked in advance. Clinics, salons, services, classes.
Abandoned cart recovery
Effective, and the easiest to overdo. One message, not a sequence of three.
Support and questions
People prefer it to phone queues and email. Works well as long as a human is reachable.
What gets your number blocked
Messaging people who did not opt in. High block and report rates from users. Sending promotional content through templates approved for other purposes. Sending at high volume from a new number with no warm-up. Blocks pile up against your number's quality rating. A poor rating cuts how many people you are allowed to message.
Worth stating plainly, because advice written for one market misleads people in another.
In some places WhatsApp is simply how people talk to each other. Much of South Asia, Latin America, and parts of Africa and Europe. There, a business using it for support and updates is completely normal. Customers often prefer it to everything else.
In places where WhatsApp is mostly personal chat among a smaller group, a surprise business message feels a lot more intrusive.
So look at what is normal where your customers are, rather than at what a case study from another continent reports.
