Almost every conversation we have about WhatsApp starts with the same mix-up. A business says "we already use WhatsApp Business, so we are set," and what they mean is the free green app on someone's phone. That is a different product from the one that connects to your CRM, and the difference decides what you can automate.

Two products, one confusing name

Meta sells two separate things. They share branding, so the names do very little to tell them apart.

WhatsApp Business App

The free app you install on a phone. It gives you a business profile, a catalog, labels, away messages and quick replies. A person reads and answers every message by hand. It is genuinely good, and for a lot of small businesses it is all they need. The main WhatsApp Business App limitation is that it cannot talk to your other systems, so nothing that arrives there shows up in your CRM, your ticket queue or your reporting unless somebody retypes it.

WhatsApp Business Platform (Cloud API)

There is no app to install. The WhatsApp Business API is something other software talks to, which is what makes it useful: an AI agent can answer at 2am, messages can open tickets, conversations can sit in the same inbox as your calls, and everything is logged. This is the one that is metered, and it is the one people are surprised by, because they were picturing the free app.

WhatsApp Coexistence: you no longer have to choose one number

This used to be the painful part. Registering a number with the API disconnected it from the Business app, so you either kept your familiar phone inbox or you got automation, and moving meant telling customers a new number.

Meta's Coexistence functionality removed that trade-off. A supported WhatsApp Business App number can run on the WhatsApp Cloud API at the same time, messages sent from either side are mirrored to the other, and your team keeps answering from the phone they already use. During onboarding you can sync your contacts and all chat messages from the most recent six months, so you are not starting from an empty inbox.

There are trade-offs worth knowing. Numbers running in Coexistence have a fixed throughput of 20 messages per second. Group chats, disappearing messages, view-once messages, live location sharing and broadcast lists are not supported or are disabled. WhatsApp for Windows and WearOS are not supported as linked devices. The contact and history sync runs once per onboarding and has to be completed within 24 hours of onboarding, otherwise you have to onboard again.

How WhatsApp Business Platform billing works

The Platform is metered per message rather than as a flat monthly fee. What a message costs depends on its category, on the country you are messaging and on your volume, so there is no single sticker price that is true for everyone.

Template categories and service messages are not the same thing

This trips people up, so it is worth separating clearly. There are three template categories. A template is a message you write in advance, submit to Meta, and send once it is approved:

Marketing. Promotions, offers and re-engagement. The most expensive category.
Utility. Transactional notices tied to something the customer did, like a booking confirmation or a reminder.
Authentication. One-time passcodes and login codes.

Service messages are different. They are not a template category at all. They are the ordinary free-form replies you send while a customer service window is open, written in your own words with nothing pre-approved. That distinction matters, because the two are billed under different rules and those rules are changing.

The two windows that decide your bill

The economics hinge on two timers, and using them well is the difference between a sensible bill and a silly one.

The 24 hour customer service window. When a customer messages you, a 24 hour customer service window opens. While it is open you can generally reply with free-form messages instead of pre-approved templates, subject to Meta's current pricing rules. The window closes 24 hours after the customer last messaged you, and after that you can only reach them with an approved template.
The free entry point window. This is a separate window, not just a longer version of the first one. It applies when someone reaches you through a qualifying Click to WhatsApp ad or an eligible Facebook Page call-to-action button. A normal 24 hour window opens, and if you respond within it, a free entry point window opens from the moment you replied and stays open for 72 hours. While that window is open you can send any type of message to that person at no charge. If you advertise on Click to WhatsApp, this is a genuine advantage and worth building your response process around.

The practical takeaway: answering people who wrote to you is the cheap part. Deliberately starting conversations with people who did not is where cost accumulates.

What is changing on 1 October 2026

Meta has announced pricing changes affecting service messages that take effect on 1 October 2026. In short, service messages are moving to per-message billing rather than being free inside the customer service window, and the treatment of utility templates inside that window is changing too. Meta has said final rates will be published ahead of the launch date. This only affects the WhatsApp Business Platform. The consumer WhatsApp app and the free WhatsApp Business App are not affected.

If you have been modelling WhatsApp on the assumption that inbound replies are free forever, that assumption has an expiry date, and it is worth revisiting your numbers now rather than in October.

A note on pricing generally: Meta revises WhatsApp Business pricing and its rate card periodically, including country-level rate changes and billing-currency migrations. Always check Meta's current published rates and rules for your markets before committing to a budget, and talk to us and we will quote you a rate for your markets and expected volume.

WhatsApp API messaging limits: you start small and earn volume

You do not get to message the world on day one. Messaging limits cap how many unique customers you can start a conversation with in a rolling 24 hour period. Replies inside an open window do not count against the cap.

Two things surprise people here. First, newly created business portfolios can start as low as 250 unique customers per 24 hours. Second, the limit is calculated at the business portfolio level and shared across every phone number in that portfolio, so adding more numbers does not buy you more headroom.

The tiers run 250, 2,000, 10,000, 100,000 and unlimited. Getting from 250 to 2,000 happens by any of:

verifying your business with Meta,
having a partner verify your business, or
delivering 2,000 messages outside customer service windows to unique numbers within a 30 day moving period, using templates with a high quality rating.

From 2,000 upward it scales automatically. Meta moves you to the next tier when you are consistently sending high-quality messages across your numbers and templates, and you have used at least half your current limit in the last 7 days. When you qualify, the increase typically lands within about six hours.

Other limits worth knowing before you commit

None of these are dealbreakers, but they all surprise somebody eventually.

Templates are submitted for approval. Anything sent outside an open window has to use a message template you submit to Meta, which reviews it, assigns it a category, and continues to enforce quality on it after approval. Review times vary, and a template can be re-categorised or restricted later, so build and submit campaign templates ahead of time rather than the morning you want to send.
Quality is scored, and it can go down. Blocks and reports from recipients drive a quality rating. Let it slide and your limits get cut. This is why buying a list and blasting it is a fast way to lose the channel.
Marketing needs opt-in. You need the customer's permission before sending promotional templates.
Business verification matters more as you grow. You can get started and send at the entry tier before completing full Meta business verification. Verification is what unlocks higher messaging limits, display name approval and various other capabilities, so treat it as something to complete early for production use rather than an obstacle to trying the platform.
Media has hard caps. Images 5 MB, audio and video 16 MB, documents 100 MB, stickers 100 KB static or 500 KB animated. Video needs H.264 with AAC audio.

So which one do you need?

If one or two people can comfortably keep up by hand, and you do not need WhatsApp conversations to appear anywhere else, the free Business app is the right answer and you should not pay for anything.

The Platform starts paying for itself when the questions repeat. Most inbound WhatsApp volume is the same handful of questions worded differently: what does it cost, how do I sign up, are you open, where are you. That is exactly the work an AI agent absorbs, at any hour, without anyone watching a phone.

How this works with Voice360

We connect the WhatsApp Business Platform to the same place your calls and SMS already live, so a WhatsApp thread is not a separate island. The same AI agent that answers your phone can answer WhatsApp, using the same knowledge base and the same handoff rules, and every conversation lands in the same history your team already works from.

If you are weighing it up, the useful first question is not what a message costs. It is how many of the conversations you get are people asking something you have already answered a hundred times. That number tells you whether this is worth doing.

WhatsApp Business App vs WhatsApp Business Platform: What You Are Actually Buying