Connect WhatsApp to Calendly — send booking reminders
Bridge Calendly bookings to WhatsApp reminders via Google Calendar. Zellbox picks up every Calendly booking and fires 24h + 2h WhatsApp reminders automatically.
by Nacho CollNacho founded Zellbox to give appointment-driven small businesses — clinics, salons, spas, physio, aesthetics, vets, mental-health, and fitness studios — a WhatsApp-first calendar and customer record system.
Editorial disclosure: I work at Zellbox. Calendly steps described from their Google Calendar integration docs as of August 2026.
Calendly handles booking. Zellbox handles what Calendly doesn’t: WhatsApp reminders. The bridge is your Google Calendar — Calendly already writes bookings there, and Zellbox reads from the same calendar.
How it works
- In Calendly → Account → Calendar Connections → connect your Google Calendar (add-to-calendar destination).
- In Zellbox → Onboarding step 2 → connect the same Google Calendar.
- Every Calendly booking now appears on your calendar. Zellbox fires WhatsApp reminders at 24 h and 2 h before the event using your approved WhatsApp template.
What Zellbox adds beyond Calendly’s built-in reminders
- WhatsApp channel (Calendly natively supports email + SMS on paid tiers, not WhatsApp).
- Higher delivery rate in LATAM, Southern Europe, MENA, SEA where WhatsApp beats SMS.
- Signed consent PDFs for services that need them (aesthetics, minor procedures).
- Two-way replies — customer replies to the reminder go into your Zellbox inbox.
Feature summary
| Zellbox layer | Calendly built-in | |
|---|---|---|
| Booking + rescheduling | via Calendly | Native |
| Email reminders | Not the focus | Native |
| SMS reminders | Not the focus | Paid tier |
| WhatsApp reminders | Native + free tier | Not available |
| Signed consent PDFs | Native | Not available |
Free to try — no credit card, no BSP setup, ~10 min end-to-end.
About the author: Nacho Coll is the founder of Zellbox. He writes about WhatsApp Business automation for appointment-driven small businesses.
Frequently asked questions
How does Calendly connect to WhatsApp via Zellbox?
Do I need a paid Calendly plan?
What phone number does the reminder come from?
About the author
Nacho Coll
Founder & Engineer at Zellbox
Nacho founded Zellbox to give appointment-driven small businesses — clinics, salons, spas, physio, aesthetics, vets, mental-health, and fitness studios — a WhatsApp-first calendar and customer record system. Writes about WhatsApp Business automation, no-show economics, recall-cycle playbooks, and the operational realities of running visit-driven businesses at scale.
