Calendly + WhatsApp API Integration — Complete Guide 2025

Calendly books the meeting. WhatsApp ensures the person shows up. Connect Calendly to WA.Expert and every booking gets an instant WhatsApp confirmation, a 24-hour reminder, and a 1-hour final nudge — cutting no-shows by 48% vs email reminders.

Connect Calendly + WhatsApp → Talk to an Expert

48%

Reduction in no-shows with WhatsApp reminders

Instant

WhatsApp booking confirmation fires on Calendly event

3 reminders

Confirmation + 24hr + 1hr before — optimal sequence

Any event

Works with all Calendly event types

What You Can Automate

Top use cases for Calendly + WhatsApp API

Calendly is the most popular appointment scheduling tool globally. WA.Expert connects to Calendly so every booking, cancellation, and rescheduling fires a WhatsApp notification — replacing unreliable email reminders with 94%-open-rate WhatsApp messages.

📅

Booking confirmation → WhatsApp

New Calendly booking fires instant WhatsApp confirmation with date, time, meeting link and agenda.

⏰

24-hour reminder → WhatsApp

Automated WhatsApp the day before with meeting details and prep instructions.

🔔

1-hour final reminder → WhatsApp

Final WhatsApp 1 hour before with direct join link and host contact.

❌

Cancellation → instant WhatsApp

Calendly cancellation fires WhatsApp to both parties with reschedule link.

Trigger → Action

How Calendly events trigger WhatsApp messages

Calendly trigger	WhatsApp action (WA.Expert)	Business impact
Invitee books (invitee.created)	Instant WhatsApp confirmation with meeting details + join link	94% confirmation read rate
Booking created	24-hour WhatsApp reminder (via delay)	−32% no-shows
Booking created	1-hour WhatsApp reminder (via delay)	−16% additional no-shows
Invitee cancels (invitee.canceled)	WhatsApp to both parties with reschedule link	Graceful cancellation handling
Meeting completed	WhatsApp follow-up with next steps or recording link	Post-meeting nurture

Setup Guide

How to connect Calendly to WhatsApp API

Set up Calendly webhook

In Calendly: Integrations → Webhooks → Create Webhook. Enter your WA.Expert webhook URL. Select events: invitee.created (booking) and invitee.canceled (cancellation).

Alternatively, use Zapier

In Zapier: Calendly → New Invitee trigger. This works on all Calendly plans and is simpler to set up than a custom webhook.

Map Calendly fields to WhatsApp

Map invitee.phone_number (if collected) or invitee.email to identify the contact. Map event_name, start_time, and meeting_link to WhatsApp template variables.

Set up reminder delays

For 24-hour and 1-hour reminders: use Zapier's Delay step or Make's Sleep module. Calculate the delay from the event start_time minus 24 hours / 1 hour. Fire the WA.Expert action after the delay.

Add phone collection to Calendly

In Calendly event settings → Questions → Add Question → Phone Number. Make it required. This ensures every booking has a phone number for WhatsApp delivery.

Sample Calendly → WhatsApp configuration

// Calendly Webhook → WA.Expert
// Event: invitee.created
{
  "event": "invitee.created",
  "payload": {
    "name": "Priya Sharma",
    "phone_number": "+919876543210",
    "event_start_time": "2026-04-10T14:00:00Z",
    "event_name": "30-min Strategy Call",
    "location": "https://zoom.us/j/..."
  }
}

// WA.Expert: send confirmation template
// Schedule 24hr reminder via Zapier Delay

WA.Expert handles WhatsApp API authentication, template approval, and delivery — you only pass the trigger data from Calendly. No WhatsApp API expertise needed on your end.

FAQ

Calendly + WhatsApp — common questions

Does Calendly have a native WhatsApp integration?

Calendly does not have a native WhatsApp integration — but it supports webhooks (Team and Business plans) and Zapier (all plans). WA.Expert connects via either route. Zapier is the simplest approach for most users.

How do I collect phone numbers in Calendly for WhatsApp?

In Calendly event settings: Questions → Add Question → Phone. Set it as required. This adds a phone number field to your booking form — every invitee must enter their phone. WA.Expert normalises Indian mobile numbers automatically.

Can I send WhatsApp reminders at specific times before a meeting?

Yes — using Zapier Delay or Make Sleep module, you can calculate the exact time 24 hours before the meeting start and trigger the WA.Expert message at that time. This requires a paid Zapier plan (Multi-Step Zaps) or any Make plan.

What happens if the meeting is cancelled?

Calendly fires an invitee.canceled webhook event. WA.Expert sends an immediate WhatsApp to the invitee acknowledging the cancellation and including a reschedule link (Calendly's scheduling link for the same event type).

Can I use Calendly + WhatsApp for group events?

Yes — Calendly group events fire the same webhook events. All invitees get WhatsApp reminders. For webinars with hundreds of registrants, test with a small group first to ensure delivery rates are acceptable before scaling.

Does this work with Calendly Free?

Calendly Free does not support webhooks. Use Zapier's Calendly integration instead — Zapier's "New Invitee" trigger works with all Calendly plans including Free. The Zapier Free plan allows up to 5 Zaps and 100 tasks/month, which covers low-volume usage.

Related Integrations

More WhatsApp integration guides

Ready to connect Calendly to WhatsApp?

Instant booking confirmation, 24hr and 1hr reminders, cancellation handling — all on WhatsApp. Cut your no-shows by 48% starting today.

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