WhatsApp Business for small businesses — full setup guide 2026

WhatsApp now sits on the home screen of roughly 75% of UK adults. Customers prefer it for confirmations, reminders and "is my car ready yet?" messages — open rates run around 95% versus 20% for email and 60% for SMS. For most small businesses, getting WhatsApp Business set up correctly is a one-afternoon project with a five-year payoff. Doing it wrong — using a personal account, ignoring GDPR consent, picking the most expensive API tier when you don't need it — costs you a few hundred pounds a year and the occasional ICO letter.

This guide walks through the three flavours of WhatsApp Business, which to pick, how to set it up, and the pitfalls that aren't in Meta's documentation.

The three flavours, demystified

WhatsApp Business app (free)

A free Android/iOS app, distinct from regular WhatsApp. You install it on a phone, register with a business number, and you get business profile features (hours, address, catalogue, quick replies). You answer messages on the phone itself, just like consumer WhatsApp.

Best for: Solo operators, microbusinesses, anyone whose total WhatsApp volume is under ~50 conversations a week.
Weakness: One device, one user. No proper team inbox. No automation. No integration with CRM or booking tools. If you ever need a colleague to reply, you can't share access cleanly.

WhatsApp Business API (legacy)

The original B2B route. Meta only sells it through approved Business Solution Providers (BSPs) like Twilio, MessageBird, Vonage. Hosted on the BSP's infrastructure, billed per conversation. Powerful but ~30% more expensive than Cloud API for identical functionality.

Best for: Almost nobody in 2026. The Cloud API has functional parity at lower cost. The exception is enterprises with existing BSP contracts and procurement constraints.

WhatsApp Cloud API (recommended for most)

Launched by Meta in 2022 and now the default. Hosted by Meta themselves, accessed via the Graph API. Free tier (1,000 service conversations per month) plus pay-as-you-go. Works with any tool that can hit a REST API — Twilio, Zapier, n8n, and any modern CRM or booking platform.

Best for: Any small business doing more than 50 conversations a week or wanting team-inbox functionality.
Weakness: The setup is fiddlier than the app — you'll spend an hour on it, not five minutes.

Step-by-step UK Cloud API setup

1. Have a Facebook Business Manager account. If you don't, go to business.facebook.com and create one. It's free.
2. Verify the business. Upload a utility bill or Companies House document. Verification takes a few hours to a few days.
3. Pick a phone number. It must be a number that isn't currently on WhatsApp. Most businesses buy a new number from Twilio or use a dedicated landline they don't already use for personal WhatsApp. Mobile numbers work too.
4. Create a WhatsApp Business Account inside Business Manager. Settings → WhatsApp Accounts → Add. Assign your number to it.
5. Receive the verification code by SMS or voice call (be ready — it expires fast).
6. Generate a permanent access token. Don't use the temporary 24-hour token Meta gives you by default. Create a System User in Business Manager, give it the whatsapp_business_messaging permission, and generate a never-expiring token.
7. Configure the webhook — the URL Meta will POST to when a customer sends you a message. If you're using Vimub, Twilio, or Zapier, they give you the URL.
8. Submit a message template for any outbound message you want to send to customers who haven't messaged you in the last 24 hours. Meta reviews templates in a few hours.

Total elapsed time: about an hour of active work, plus a few hours of waiting for verification. For most businesses, doing this with a tool that abstracts steps 6–8 (Twilio, Vimub) saves real time.

Phone number portability

You can port a number you already own (a Twilio number, a landline) into WhatsApp Cloud API. You cannot port a number that's currently registered on consumer WhatsApp — you'd need to delete its WhatsApp account first, wait, and then re-register on the API. Plan for this if you're moving an established business number.

Two patterns we recommend:

• New dedicated number. Buy a fresh Twilio or local landline number for WhatsApp Business. Cleanest separation.
• Existing business landline. If your customers already know a specific number, port it. Worth the temporary inconvenience.

GDPR and the consent question

The UK GDPR treats WhatsApp marketing messages the same way it treats SMS marketing — you need explicit, opt-in consent. Three rules:

1. Opt-in must be specific. "I agree to receive WhatsApp messages about my booking and occasional offers" is fine. "I agree to terms and conditions" buried somewhere is not.
2. Opt-out must be easy. Every marketing message must offer a clear way to stop — typically "Reply STOP to unsubscribe".
3. Transactional messages (booking confirmations, repair-ready notifications) don't need explicit marketing opt-in — but the customer must have given you their number in the context of the transaction.

The ICO has not (as of mid-2026) issued a major WhatsApp-specific fine, but the rules they'd apply are the same ones they apply to SMS. Don't be the test case.

Real costs

Meta's pricing model is per-conversation (not per-message), and a conversation lasts 24 hours from the first message. UK pricing in 2026:

• Service conversations (customer-initiated): 1,000 free per month, then ~£0.005 each.
• Utility conversations (transactional templates — order updates, appointments): ~£0.012 each.
• Marketing conversations (promotional templates): ~£0.05 each.
• Authentication conversations (OTP codes): ~£0.025 each.

For a typical small business doing ~300 customer conversations a month, the cost is in the £5–£15/mo range, before any tool you use to manage it. Tools like Twilio, MessageBird and Vimub add a per-message or per-seat fee on top — usually £30–£100/mo all-in.

Integration with Zapier and other tools

Once your Cloud API is set up, you can wire it to almost anything. The common patterns:

• Booking confirmation: Calendly / Vimub → Zapier → WhatsApp Cloud API template message.
• Repair-ready: ticket-status change in your repair POS → webhook → WhatsApp template.
• Review request: invoice paid in QuickBooks / Stripe → 90-minute delay → WhatsApp template with the Google review link.
• Customer reply handling: incoming WhatsApp → Zapier → assignment to a teammate inside your CRM.

Common pitfalls

• Using personal WhatsApp for business. Against Meta's terms; you'll lose the account when (not if) you're reported.
• Forgetting the 24-hour window rule. Outside of an active customer conversation, you can only send approved template messages. Free-form replies after 24 hours of silence get blocked.
• Sending marketing messages without explicit opt-in. Meta will throttle your number; the ICO will potentially fine you.
• Not setting up automated greetings and away messages. A customer who messages at 11pm and hears nothing assumes you're closed forever. A simple "we'll be back at 8am" message keeps them.
• Picking the legacy Business API in 2026. It's more expensive than Cloud API for identical functionality. The only reason to pick it is an enterprise procurement constraint.

How Vimub helps

Vimub wires WhatsApp Cloud API into the same unified inbox as your Google reviews, SMS, Facebook messages and webchat. We handle the template submissions, the opt-in capture, the opt-out keywords, and the 24-hour-window logic. Your customers see one consistent channel, and you reply from a single screen. Start a 14-day trial — we'll do the WhatsApp setup with you on a 30-minute call.