Messaging
Updated Oct 2026
SMS vs WhatsApp reminders
One is universal and costs money per message. The other is free per message and depends entirely on the client having the app and not muting you.
Short answer
Use WhatsApp where your clients use it, fall back to SMS for everyone who does not. Do not pick one channel for everyone — you will lose either money or reach.
Real costs
| SMS | ||
|---|---|---|
| Per message | ~$0.01-0.08 depending on country | Free in 24h service window |
| Delivery proof | Reliable but no read receipt | Read receipts where enabled |
| Works without data | Yes | No |
| Rich content | No | Yes (buttons, images, location) |
| Setup friction | None | Business account + template approval |
Where WhatsApp wins
- Confirm buttons. A one-tap "Confirm / Reschedule" gets far more replies than "reply YES".
- Location pins. Eliminates the "where exactly?" call.
- Free messages inside the 24-hour service window. If the client messaged you, your reply costs nothing.
- Photo context. Before/after, colour formulas, intake forms.
Where WhatsApp fails
- Template approval. Business-initiated messages outside the service window need pre-approved templates. Approval takes time and rejections happen.
- Muted business chats. Users mute aggressively; a muted thread may never be seen.
- Older clients. In many markets, SMS still reaches a chunk of your list that WhatsApp does not.
- No data, no message. Dead battery with no data means no reminder.
What I would run
Two-step reminders, channel chosen per client: WhatsApp if they booked through a WhatsApp link or replied to one before, SMS otherwise. Keep the wording identical so your reply-rate data is comparable.
If you are on a booking platform, check whether it supports per-client channel selection. Booksy and Fresha both lean on SMS by default; WhatsApp usually requires an add-on or a separate API provider.
The number that matters
Cost per confirmed appointment, not cost per message. A $0.05 SMS that gets confirmed beats a free WhatsApp message that sits unread. Track confirmed-per-sent for both channels for two weeks before you decide.