The verdict in three sentences
Your B2B customers in London read WhatsApp faster than e-mail: connecting the WhatsApp Business API to your web app cuts where-is-my-order calls and speeds up payment. Integration costs roughly 5,000 to 15,000 GBP, then per-message fees that vary widely by category, from about 1.5 pence for a utility notification to over 5 pence for marketing. SMS remains a useful fallback for customers who do not use WhatsApp, and a dual setup typically pays back within a year.
WhatsApp, SMS or both: the 2026 comparison
| Criterion | WhatsApp Business API | SMS via aggregator | Free WhatsApp Business app |
|---|---|---|---|
| Unit cost (2026 estimate, UK) | About 1.5 to 5.5 pence per template message | 3 to 5 pence per SMS | 0 |
| Automation from your app | Yes, via API | Yes, via API | No, manual |
| Observed read rate | 80 to 95% | 60 to 80% | 80 to 95% |
| Rich content | Buttons, PDFs, location, payment links | 160 characters, text only | Yes, but manual |
| Prior approval | Templates approved by Meta in 24 to 48 h | Sender ID setup | None |
| Customers without WhatsApp | Unreachable | Reachable | Unreachable |
| Realistic volume | Unlimited per Meta tier | Unlimited | 50 to 100 messages per day per agent |
Since July 2025, Meta charges template messages individually by category: marketing (the most expensive), utility (order confirmation, delivery) and authentication (one-time codes). Replies sent within 24 hours of a customer message are free, as are utility templates sent inside that window. A well-run distributor mostly pays for delivery notices and reminders.
What the integration includes
| Work package | Content | Duration | Indicative budget (market estimate) |
|---|---|---|---|
| Scoping and Meta account | Business verification, dedicated number, provider (BSP) choice | 1 week | 500 to 1,000 GBP |
| Message templates | Drafting, Meta approval | 1 week | 300 to 800 GBP |
| WhatsApp connector | Sends triggered by order statuses, read-receipt webhooks | 1 to 2 weeks | 2,000 to 6,000 GBP |
| SMS fallback | Aggregator, switch if WhatsApp undelivered | 3 to 5 days | 800 to 2,000 GBP |
| Payment reminders | Stripe or open-banking link in the message | 3 to 5 days | 700 to 1,700 GBP |
| Dashboard | Read rates, costs, opt-outs | 3 to 5 days | 700 to 1,500 GBP |
| Total | 3 to 6 weeks | 5,000 to 15,000 GBP |
In francophone West Africa, the same integration scope is estimated at 1,500,000 to 3,500,000 FCFA (about 2,290 to 5,340 EUR, 2026 market estimate). If your application must be rebuilt at the same time, the project moves into Kolonell's custom application ranges: 2,500,000 to 4,000,000 FCFA (3,810 to 6,100 EUR) for a simple app, 4,000,000 to 7,000,000 FCFA (6,100 to 10,670 EUR) for a medium one with several integrations.
Rules to follow to avoid being blocked
Meta gives each number a quality rating. Too many reports and your daily limit drops, or the number is suspended. Only send marketing to customers who opted in, offer a Stop button, and keep service notifications separate from promotions. In the UK, marketing messages also fall under PECR and UK GDPR: consent must be recorded and provable, with ICO fines possible for unsolicited marketing.
Mini case study
Priya, operations director of a catering supplies distributor in London, handles 2,400 deliveries per month to 600 restaurants. Her team takes 1,800 tracking calls a month at about 4 minutes each, 120 hours. She sends 3 messages per delivery: 7,200 utility templates at about 2 pence, 144 GBP per month, plus 500 SMS fallbacks at 4 pence, 20 GBP. Removing 60% of calls frees 72 hours a month; at 18 GBP per loaded hour, that is 1,296 GBP per month. Payment reminders with a link also cut average collection time from 34 to 27 days. With a 10,000 GBP integration, payback on time saved alone is around 9 months.
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FAQ
Do we need a dedicated phone number?
Yes, a number connected to the API can no longer be used in the regular WhatsApp app. A new UK mobile number costs a few pounds per month, or you can migrate an existing one after backup.
How long does Meta take to approve a template?
Usually 24 to 48 hours, sometimes minutes. A promotional template submitted as utility will be reclassified or rejected, adding 1 to 2 days.
Can we send PDF invoices over WhatsApp?
Yes, a template can carry a document of up to 100 MB. Restaurant owners often prefer this to e-mail.
What if the customer does not read the WhatsApp message?
The connector switches to SMS after a set delay, for example 2 hours, for an extra 3 to 5 pence per message.
Is a chatbot included?
No, the integration covers notifications and manual agent replies. A chatbot that answers tracking questions adds roughly 1,500 to 5,000 GBP depending on complexity.
Let's scope your project. Share your order volume, your current app and the messages to automate: we price the integration, the monthly messaging cost and the timeline. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.
Mohamed Bah
Fondateur, Kolonell
Passionate about digital and entrepreneurship in Africa, Mohamed has been helping Sénégalese businesses with their digital transformation since 2020. Founder of Kolonell, he believes every SME deserves a professional and accessible online présence.
