Editorial disclosure: I work at Zellbox. SimplyBook.me described from their Google Calendar Sync docs as of August 2026.
SimplyBook.me is an online booking platform popular with service businesses across many markets. Zellbox adds WhatsApp reminders via the Google Calendar sync SimplyBook already offers.
How it works
- In SimplyBook.me → Custom Features → Google Calendar Sync → enable.
- In Zellbox → Onboarding step 2 → connect the same Google Calendar.
- Every SimplyBook booking now lands on your calendar. Zellbox fires WhatsApp reminders at 24 h and 2 h.
What Zellbox adds
- WhatsApp reminders — SimplyBook does email + SMS natively, but WhatsApp isn’t a first-class notification channel inside the platform; the Google Calendar sync is what makes a WhatsApp reminder possible without leaving SimplyBook for bookings.
- Signed consent PDFs for services requiring them — useful for beauty, aesthetic, and wellness bookings where a signed treatment or liability waiver needs to sit on the customer record, something SimplyBook’s native reminder flow doesn’t produce.
- Two-way replies land in your Zellbox inbox — when a customer replies to reschedule, the message shows up attached to that customer’s record instead of scattered across a staff member’s personal phone.
Before you start: check your plan
Google Calendar Sync is one of SimplyBook’s paid custom features, not part of the free tier — so confirm it’s enabled on your account before setting up the Zellbox bridge.
Confirm Google Calendar Sync is enabled
In SimplyBook.me, go to Custom Features and check whether Google Calendar Sync shows as active. If it’s greyed out, you’ll need to upgrade from the free plan or add the feature to your current paid plan — SimplyBook’s pricing page has the current feature-by-tier breakdown, since it changes from time to time.
Decide which booking types should sync
If you run several service categories through SimplyBook (say, both walk-in-friendly services and appointment-only services), you don’t have to sync all of them to the same Google Calendar. Scoping the sync to just the categories that actually need a WhatsApp reminder keeps the calendar — and the Zellbox reminder schedule built from it — free of noise from bookings that don’t need a nudge.
Feature summary
| Zellbox layer | SimplyBook built-in | |
|---|---|---|
| Booking + payments | via SimplyBook | Native |
| Email + SMS reminders | Not the focus | Native |
| WhatsApp reminders | Native + free tier | Not available |
| Signed consent PDFs | Native | Custom intake form |
Free tier covers 100 reminders/month.
About the author: Nacho Coll is the founder of Zellbox. He writes about WhatsApp Business automation for appointment-driven small businesses.
