# WhatsApp Business API

> How the WhatsApp Business API differs from the WhatsApp app you already use, and the rules it brings.
> Source: https://onpad.in/docs/whatsapp-business-api

Most people arrive here using one of two WhatsApp apps already, and the third thing — the one ONPAD runs on — works differently enough that it is worth ten minutes before you sign up.

## The three WhatsApps

**WhatsApp Messenger** is the personal app. One phone, one person, no business features.

**WhatsApp Business app** is the free app for small businesses. It adds a business profile, catalogues, quick replies and labels. It still runs on one phone, and only one person can use it at a time.

**WhatsApp Business Platform (the Cloud API)** is what ONPAD uses. There is no phone and no app. Your number lives on Meta's servers, and software connects to it. That is what lets a whole team answer at once, lets you message thousands of people, and lets your website send messages on its own.

A number can only be in one of these at a time. Moving a number to the API means it leaves the app — see [Before you start](https://onpad.in/docs/before-you-start).

## The rules the API brings

These are Meta's rules, not ONPAD's. No platform can remove them, and any platform that claims to is worth avoiding.

### You cannot message someone first in free text

To start a conversation with a customer, you must use a **message template** that Meta approved in advance. You write the template, submit it, and wait for a decision — usually minutes, sometimes a day.

This is why campaigns can only use approved templates, and why you cannot type a new offer and blast it out immediately. See [Your first template](https://onpad.in/docs/your-first-template).

### The 24-hour customer service window

When a customer messages you, a 24-hour window opens. Inside it, you can reply with anything — free text, images, documents, voice notes. No template, no approval.

When it closes, free text is no longer allowed. The only way back to that customer is an approved template, which starts a fresh conversation. Their next reply opens a new 24-hour window.

ONPAD shows you when a window has closed and offers to send a template instead, so you will not write a reply that cannot be delivered.

### Template categories

Every template is one of three categories, and the category decides the rules and the price:

- **Marketing** — offers, announcements, anything promotional. The most likely to be rejected if it reads like spam, and customers can opt out of it.
- **Utility** — about something the customer already did: an order update, a delivery notification, an appointment reminder, a payment receipt.
- **Authentication** — one-time passcodes only. Meta fixes the wording tightly and allows very little variation.

Meta can re-categorise a template by itself if it disagrees with your choice. Labelling a promotional message as Utility does not make it cheaper; it usually makes it rejected.

### Messaging limits and quality rating

Meta gives every number a **messaging limit** — how many different customers you may start a conversation with in 24 hours — and a **quality rating** of green, amber or red based on how customers react to you.

The limit rises on its own as you send messages people welcome. It falls when customers block or report you. A red rating can pause the number entirely.

To protect both:

- Only message people who expect to hear from you.
- Keep marketing relevant and not too frequent.
- Honour opt-outs immediately.

Neither the limit nor the rating is something ONPAD sets, and no ONPAD plan changes them.

## What this means in practice

If you are used to the WhatsApp Business app, three habits have to change:

1. **Plan your outbound messages in advance.** Templates need approval, so the offer you want to send tomorrow should be submitted today.
2. **Reply inside the window.** A customer who messaged you yesterday afternoon is reachable in free text until this afternoon, and not after.
3. **Build a list of people who want to hear from you.** Buying a contact list is the fastest way to a red quality rating and a paused number.

## Next

- [Before you start](https://onpad.in/docs/before-you-start) — what you need ready before signing up
- [What it costs](https://onpad.in/docs/what-it-costs) — Meta's charges and ONPAD's, which are separate