WhatsApp Business API UK

The WhatsApp Business API, without the integration project

Line registers your sender, runs the webhooks, and manages templates and the 24-hour window — so your team gets API-grade WhatsApp through a simple shared inbox.

Connected directly to Meta's WhatsApp Business Platform.

Everything the API demands, handled for you

The WhatsApp Business Platform normally means developers, webhooks, and compliance rules. With Line it means opening Settings.

Sender registration, done for you
Line registers your business number on the WhatsApp Business Platform through a guided setup in Settings. No developer, no API keys, no back-and-forth with documentation.
Webhooks and infrastructure handled
Line connects directly to Meta's Cloud API and handles webhooks, delivery callbacks, and session state behind the scenes. Messages simply appear in your inbox.
The 24-hour window, managed
Line tracks WhatsApp's customer service window on every conversation, so free-form replies go out when they are allowed and templates are used when they are required.
Template messages made simple
Approved template messages let you start or re-open conversations outside the 24-hour window. Line handles the mechanics, so you never send something WhatsApp will reject.
An inbox, not an API console
Your team replies to WhatsApp from the same shared inbox as SMS and calls — with assignments, internal notes, and a full contact timeline. No dashboards built for developers.
Automation and AI agents on top
Line's AI agents can answer WhatsApp messages in triage, assist, or autonomous mode, with approval gates. The kind of automation the API was built for — without writing any of it.

How the WhatsApp Business API works with Line

Four steps from sign-up to WhatsApp conversations in your inbox.

1

Register your sender

Follow the guided setup in Settings. Line registers your UK business number as a WhatsApp sender on the WhatsApp Business Platform.

2

Verify your business details

Confirm your business name and profile as part of registration. If Meta asks for business verification, the setup walks you through exactly what is needed.

3

Messages flow into your inbox

Once your sender is live, WhatsApp messages arrive in your shared inbox alongside SMS and calls — no webhooks to build, no servers to run.

4

Reply, automate, or hand to an agent

Your team answers from the inbox, automations handle the routine, and AI agents can reply within the service window. Templates re-open conversations when it closes.

When you need the API, not the app. And a team inbox, not a developer console.

The WhatsApp Business app is fine for one person and one phone. The moment a team is involved, you need the platform underneath.

Outgrown the WhatsApp Business app

The free app tops out at a handful of linked devices and one primary phone. The API has no such limits — your whole team works from one inbox.

No developer on staff

The WhatsApp Business API normally means an integration project. Line gives you API-grade WhatsApp through a product you can set up yourself.

Support that scales

Assign conversations, leave internal notes, and see the full contact timeline. Proper customer service tooling on top of the raw API.

Automated first replies

AI agents and automations respond within WhatsApp's service window, so customers get an answer even when the team is on the tools.

From the guide library

Our deep dives on the WhatsApp Business API, costs, and templates.

WhatsApp Business API FAQ

Common questions about the WhatsApp Business Platform, verification, and templates.

What is the WhatsApp Business API?

The WhatsApp Business API — now called the WhatsApp Business Platform — is Meta's way for businesses to send and receive WhatsApp messages through software rather than the WhatsApp Business app. It removes the app's device limits and enables shared inboxes, automation, and integrations, but it has no interface of its own. Line provides that interface: your team uses a shared inbox while Line handles the API underneath.

Do I need Meta Business verification?

You register your WhatsApp sender through a Meta Business account, and Meta may ask you to verify your business to unlock higher messaging limits and display your full business name. Many small businesses can start messaging before full verification is complete. Line's guided setup tells you exactly what Meta needs at each stage, so there is no guesswork.

Can I keep my existing number?

Yes. You can connect a Line number or another business number. If you already use the WhatsApp Business app, Meta's coexistence setup can keep the app active while Line handles the shared inbox, agents, and automations.

How do template messages work?

Template messages are pre-approved message formats — with placeholders for names, dates, and details — that WhatsApp requires when a business starts or re-opens a conversation outside the 24-hour customer service window. Once a customer replies, you can message freely again for 24 hours. Line manages when templates are required so your messages always comply.

What is the 24-hour customer service window?

When a customer messages you on WhatsApp, a 24-hour window opens from their most recent message. Inside the window you can send free-form replies. Once it closes, you must use an approved template message to restart the conversation. Line tracks the window on every conversation automatically.

Do I need to write any code?

No. Line connects directly to Meta's WhatsApp Business Platform and handles sender registration, webhooks, session tracking, and templates for you. You set WhatsApp up from Settings with a guided flow, and your team works entirely from the shared inbox.

Is Line a WhatsApp Business Solution Provider?

Line connects directly to Meta as a verified Tech Provider. Line handles sender registration, the shared inbox, AI agents, automations, and window and template rules in one product for small teams.

API-grade WhatsApp, small-business simple

Skip the integration project. Get a UK business number, register your WhatsApp sender from Settings, and start replying from a shared inbox.

  • Guided WhatsApp sender registration
  • Webhooks and infrastructure handled
  • Templates and 24-hour window managed
  • Shared inbox for WhatsApp, SMS, and calls
  • AI agents and automations included
  • No developer, no contracts
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Prices exclude VAT. Full pricing

Also explore: WhatsApp Business · Business SMS · AI receptionist · Shared team inbox

WhatsApp Business API UK | No Code Required | Line | Line