The short answer
WhatsApp Business API is priced per 24-hour conversation, not per message. UK 2026 rates per Meta:
| Conversation category | UK rate (per 24h conversation) | Use case |
|---|---|---|
| Marketing | £0.044 | Broadcasts, promotional content, re-engagement |
| Utility | £0.013 | Order updates, appointment reminders, transactional |
| Authentication | £0.027 | 2FA codes, login verifications |
| Service | Free for first 1,000 / month, then £0.012 | Responses to inbound customer messages |
On top of the Meta conversation fees, you pay one of:
- A Business Solution Provider (BSP): 360dialog, Twilio, MessageBird, infobip. Typically £0 to £50 / month base plus per-conversation passthrough.
- A managed platform: Wati (£39+ / mo), Sleekflow (£15+ / number), Respond.io ($79+ / mo), Trengo (€50+ / mo), or NuvenarHub (£60 to £4,200 / mo + VAT). Adds inbox, broadcaster, CRM, AI on top.
- Direct via Meta Cloud API: free, but you build the inbox, broadcaster, anti-ban, CRM, and AI agent yourself. Suitable for engineering teams; not for operators.
Worked examples
Single-location clinic, ~5,000 conversations / month
- 3,000 marketing broadcasts at £0.044 = £132
- 1,500 utility (reminders) at £0.013 = £19.50
- 500 service (inbound, mostly free tier) ≈ £0
- Meta total ≈ £151.50
- Platform (NuvenarHub Pro) = £480 / month + VAT bundled (covers 3 numbers, unlimited platform-side, AI agent, CRM, calling, attribution)
- All-in monthly: £631.50
Multi-location chain, ~25,000 conversations / month
- 15,000 marketing at £0.044 = £660
- 8,000 utility at £0.013 = £104
- 2,000 service (1,000 free, 1,000 paid at £0.012) = £12
- Meta total ≈ £776
- Platform (NuvenarHub Enterprise) = £4,200 / month + VAT (25 numbers, per-tenant proxies, multi-workspace, dedicated CSM, 99.9% SLA)
- All-in monthly: £4,976
Solo practitioner, ~500 inbound conversations / month
- 500 service conversations, all in free tier = £0
- Platform (NuvenarHub Starter) = £60 / month + VAT (1 number, 200 messages / day platform-side)
- All-in monthly: £60
Hidden costs to watch for
- Markup on conversations: some BSPs and platforms charge 10 to 30 percent on top of Meta's published rate. Check the line items. NuvenarHub passes through at exact Meta cost with no markup.
- Template approval delays: marketing templates need Meta approval, sometimes 24 to 72 hours. Plan campaign launches with that lead time.
- Number warmup period: a new WhatsApp Business number cannot blast 10,000 conversations on day one. Quality rating starts at "high" and only allows volume after established engagement. Plan a 30-day ramp.
- Restricted templates: certain content (financial product advertising, regulated health claims, alcohol in some regions) is restricted by Meta. Clinics promoting "results" should review the WhatsApp Business Policy before sending.
- Bans for high block rate: if more than 2 percent of recipients block your number, the number's quality rating drops and Meta restricts you. Anti-ban infrastructure (proxy rotation, send-rate limiting, audience hygiene) becomes critical above 10k conversations / month.
What about Meta Cloud API direct (free)?
Technically free of platform fees, but you build everything else:
- Webhook receiver for inbound messages.
- Inbox UI for your team.
- Broadcaster with template management.
- Anti-ban logic (send rate limiter, quality monitoring, proxy rotation).
- CRM contact merging and lifecycle tracking.
- AI auto-reply if you want it.
- Reporting and dashboards.
Engineering cost: 8 to 16 weeks for a usable v1, plus ongoing maintenance. Suitable only if WhatsApp is a strategic core asset and you have a senior engineering team. For everyone else, a managed platform is materially cheaper than building.
How to pick a platform
- Estimate monthly conversation volume by category.
- Multiply by the rates above to get your Meta cost.
- Add the platform fee. If a platform charges per number, multiply by your number count.
- Check for hidden markups on conversation pass-through.
- Ask the platform about anti-ban infrastructure. If they cannot answer specifically (proxy strategy, send-rate limiter, quality monitoring), assume they do not have it.
- Confirm contract is UK-jurisdictional if that matters to your procurement.
The NuvenarHub pricing page publishes the 57-row matrix so a comparison against any vendor's published rate card is a 30-minute exercise.