Blog / API & technical

WhatsApp Business API: what it is, how it works and how to activate it in 2026

This guide explains what the WhatsApp Business API is, how it differs from the app, how it works in practice and how to activate it, step by step. The rates are those of Meta’s rate card in force for Italy; the limits are those written in the official developer documentation. Where Meta does not publish a figure, you won’t find one here either.

What the WhatsApp Business API is (and what it isn’t)

The WhatsApp Business API, which Meta now calls the WhatsApp Business Platform, is the set of tools a piece of software uses to send and receive WhatsApp messages on behalf of a business. It is not an app to download: it has no chat screen, it doesn’t install on a phone and it doesn’t open in a browser. It is infrastructure. To use it you need a platform that builds an inbox, campaigns and automations on top of it, or a team of developers who write their own software.

The version in use today is Meta’s Cloud API, hosted on Meta’s servers. There was also an on-premises version, installed on the servers of the business or of its provider: Meta has retired it, and since 23 October 2025 it can no longer send messages. If an offer still talks about servers to configure or installations, it is an old offer.

Between the business and Meta there is usually a provider, called a BSP (Business Solution Provider): the platform that lets you connect the number, gives you the tools to use it and supports you. With Meta’s official procedure, Embedded Signup, the WhatsApp account is created in the business’s own business portfolio, not in the provider’s. And the rules on messages are Meta’s, whichever provider you choose.

What it isn’t: it is not WhatsApp Web, it is not a browser extension and it is not a way to send bulk messages from a personal number. Nor is it reserved for large companies: practices, shops and small online stores use it too, because messages are paid one by one and platforms have plans that suit a small business as well.

WhatsApp Business app or API: the differences

The WhatsApp Business app is free and designed for people who reply by hand from a phone. The API is for when there are many messages, more than one person replying, or when you want to automate. The main differences:

The two paths don’t exclude each other. With coexistence the same number stays on the WhatsApp Business app on the phone and is also connected to the API: you reply by hand from the app when needed and use the platform for campaigns and automations. The full comparison, with the signs that tell you when it’s worth switching, is in the guide to the differences between the WhatsApp Business app and the API.

What it’s for: use cases by industry

A few examples of how businesses use it. They are illustrative examples: each case has to be built around your own customers, their consent and the templates Meta approves.

• Appointment reminders: a medical practice or beauty salon sends a utility message the day before with the date, the time and a button to confirm or reschedule. This is the case of automatic appointment reminders.
• Abandoned cart: an online store reminds people who left products in their cart to complete the purchase, if that customer has agreed to receive messages. You can see how to set it up on the page about recovering abandoned carts.
• Orders and shipping: purchase confirmation, tracking number, delivery notice, sent automatically by the online store with order notifications on WhatsApp.
• Customer service: several agents reply from the same number, and an AI assistant covers recurring questions even outside business hours and hands delicate cases to a person, with the conversation already in front of them.
• Campaigns: promotions, new arrivals and events sent to people who chose to receive them, segmented by interests and purchase history.
• Bookings: a restaurant or hotel receives requests from an ad that leads to the chat and confirms the table or room in the same conversation.

Some industries have dedicated pages: WhatsApp for restaurants, WhatsApp for medical practices, WhatsApp for online stores; the others are collected on the industries page. Before planning a campaign, though, check that you don’t sell products Meta doesn’t allow you to promote: alcohol, tobacco and medicines are on the list of products prohibited on WhatsApp Business.

How it works: templates, the 24-hour window and categories

Who writes first changes the rules

The basic rule is simple. When the customer writes to you, a 24-hour service window opens: inside that window you reply with free-form messages, that is text, images, documents, buttons. Every new message from the customer restarts the 24 hours. Outside the window, or when you are the one writing first, you can only send a template: a message model you have prepared and Meta has approved, with variable parts such as the name or the date. The details are in the guide to the WhatsApp 24-hour window.

There is a useful exception. If the customer writes to you after tapping an ad that leads to WhatsApp or a Facebook Page button, and you reply within 24 hours, a free entry point window opens that, according to Meta’s developer pricing page updated on 28 September 2026, can last up to 7 days: inside that window all messages are free, templates included.

The four message categories

Every template belongs to a category, and the category decides the price:

• Marketing: promotions, offers, news, invitations, cart recovery. It is the most expensive category.
• Utility: updates linked to something the customer asked for or bought, such as an order confirmation, shipping or an appointment reminder.
• Authentication: one-time codes to log in to a service or confirm an operation.
• Service: not a template. These are the free-form replies you send inside the 24-hour window.

Meta checks the category when it approves the template and can change it if, for example, a message submitted as utility contains an offer. Examples and borderline cases are in the guide to WhatsApp message categories.

Consent (opt-in)

To write first to a customer you need their consent to receive WhatsApp messages from your business. Meta’s policy requires it and, for promotional messages, so does the GDPR. Consent is collected clearly, for example with a checkbox on the website form, at checkout or in store, and you must always leave a way to stop receiving messages. How to do it without mistakes is explained in the guide to collecting opt-in on WhatsApp.

How to activate it, step by step

To activate the WhatsApp Business API you need a few things, all in the business’s name:

• A Meta business portfolio, what used to be called Business Manager, with the business name, a business email and a website. If you don’t have one, you can also create it during the connection.
• A phone number that can receive an SMS or a call with the verification code: a mobile number works, but so does a landline.
• A display name, that is the name customers see in the chat, consistent with the name of the business.
• A payment method on the WhatsApp account, in the Business Manager’s Billing hub, for the messages Meta charges. Without a payment method, from 1 October 2026 Meta delivers service replies only while the number stays within the 1,000 free of the month: beyond that, they are not delivered.
• Business verification, recommended from the start: it is done with a document of the business, such as a company registration extract, a VAT registration certificate or a utility bill in the business’s name.

The steps, in the order you do them:

• 1. Choose the provider and start the connection from its dashboard: Meta’s official procedure opens, with no codes or tokens to copy.
• 2. Log in with your Facebook profile and select the business portfolio, or create one.
• 3. Create the WhatsApp Business account and set the display name and business category.
• 4. Add the number and confirm it with the 6-digit code received by SMS or through a call. If the number is already on the WhatsApp Business app, choose to connect the existing app.
• 5. Add the payment method in the Business Manager’s Billing hub.
• 6. Start business verification from the Business Manager’s Security Center.
• 7. Create your first templates and submit them for approval: from there you can reply, automate and run campaigns.

The number: a new one, or the one you already have

If the number is already on the WhatsApp Business app, with coexistence you connect it to the API and keep using it on the phone. When you connect, you can share the last 6 months of chats with the platform, a choice you make only once and cannot change later. To stay connected, the app has to be opened on the main phone at least once every 14 days or so. A number registered on the personal WhatsApp app, on the other hand, must first be removed from it. If the number is already on the API with another provider, it can be moved to a new platform with a number migration, without changing it.

Timing

The technical connection is done in one guided session. The timings that don’t depend on you are Meta’s: according to the official documentation, a template review can take up to 24 hours; business verification depends on the documents submitted and on Meta’s checks. The procedure with screenshots, including the case of those who don’t yet have a portfolio, is in the guide to creating a WhatsApp Business API account. If you use SendApp, the steps in the dashboard are in the guide on how to connect WhatsApp to the official API.

What it costs, in brief

The costs of the WhatsApp Business API are three, and it pays to look at all of them before choosing. The first is Meta’s rate for each paid message delivered: it is the same with any provider and depends on the category and on the recipient’s country, not yours. The second is the platform subscription, which pays for the software: inbox, campaigns, automations, AI. The third is less visible: the markup some providers add to Meta’s rate, per message or inside prepaid bundles. At high volumes it can weigh more than the subscription.

Source: Meta’s euro rate card in force from 1 July 2026 and Meta’s developer pricing page (updated on 28 September 2026), section “Service rates, effective October 1, 2026”, which introduces the free tier of 1,000 service messages per month per number; data updated on 29 September 2026. Rates change periodically: the official reference is the WhatsApp Business Platform pricing page.

With SendApp you pay Meta’s rate to Meta, with the payment method on your account, with no markup on Meta’s rates; you pay the platform only for the plan, from €19 a month. The full breakdown, with examples and a comparison of providers’ pricing models, is in the guide on how much the WhatsApp Business API costs. For an estimate on your own case, the WhatsApp API cost calculator adds it up by country and category.

The limits you need to know

How many customers you can contact per day

Meta limits how many different customers you can write to in 24 hours with messages outside a service window, that is when you are the one writing first. Replies to people who wrote to you don’t count. The limit applies to the whole business portfolio and is shared among its numbers. A new portfolio starts at 250 different recipients every 24 hours; the next levels are 2,000, 10,000, 100,000 and finally no cap.

To move up to 2,000, business verification is enough, or delivering 2,000 messages outside the window to different numbers within 30 days, with high-quality templates. Beyond 2,000 the limit rises on its own if messages stay good quality and in the last 7 days you have used at least half of the current limit. More detail in the guide to WhatsApp sending limits.

Message quality

Meta rates every template based on the reactions of the people who receive it: negative feedback and low read rates lower the quality from high to medium or low. A low-quality template can be slowed down or paused and, if the problem continues, lose its approved status. Quality also matters for growing your sending limits. The defence is to write only to people who have given consent, with expected messages and a clear way to stop receiving them. More tips in the guide to avoiding a number ban.

Template approval

Meta’s decision on a template can take up to 24 hours. The most common reasons for rejection, according to the documentation: badly written or out-of-sequence variables, a template that starts or ends with a variable, too many variables relative to the text, requests for sensitive data, content against the commerce policies, duplicates of an existing template. How to prepare them to pass on the first submission is explained in the guide to getting a WhatsApp template approved.

File sizes

• JPEG and PNG images: up to 5 MB.
• MP4 and 3GP video, MP3, AAC, AMR, M4A and OGG audio: up to 16 MB.
• PDF, Word, Excel, PowerPoint and text documents: up to 100 MB.
• WebP stickers: up to 100 KB if static, 500 KB if animated.

Sources: Meta’s developer documentation on messaging limits, on template review and quality, and on supported file types, consulted on 29 September 2026.

How to choose a provider

All providers use the same Meta API and messages have the same Meta rates: what changes is the software, the service and the way they make you pay for messages. Five questions to ask before signing:

• Markup: does Meta bill me for messages at its rates, or do you? If the provider bills them, what is the margin per message?
• Onboarding: is the connection made with Meta’s official procedure, and does the account stay in my business portfolio? Who helps me with business verification and the first templates?
• Support: is there support in my language, from people who know Meta’s rules, and during which hours?
• Integrations: does it connect to the e-commerce, CRM or management software I already use, or do I need a developer?
• Contract: is there an annual commitment, a setup fee, a minimum number of messages? If I change provider, do I take the number with me?

SendApp is a Meta Business Partner and works only with the official API. The number is connected with Meta’s guided procedure, also in coexistence with the app; messages are billed by Meta, with no markup on Meta's rates; plans start at €19 a month and include a shared inbox, campaigns, automations and an AI assistant, with the contact and agent limits shown in SendApp’s plans and pricing. The connections with e-commerce, CRMs and calendars are listed on the integrations page, and the overview of the offer is on the page about the WhatsApp Business API platform.

Where to start

If you already have a number and a business portfolio, the next step is to connect them and submit your first template for approval. If you don’t yet know which number to use, whether coexistence suits you or how much you’ll spend on messages, it’s better to clarify that first: costs depend on how many messages you send and in which category.