how to book appointments on WhatsApp with Google Calendar.
heysteff is an AI platform for customer support and sales across WhatsApp, Instagram, Messenger, Gmail and Shopify; Steff is the AI agent that runs it. This guide is for service businesses that want customers to book, reschedule or cancel their appointment inside the same WhatsApp chat — without jumping to a separate form and without the team checking the calendar by hand.
◆ prerequisites
A WhatsApp channel connected in your workspace, a Google Calendar account (optional but recommended for syncing), and clarity on your business hours and the standard duration of each appointment.
Step 1: Create the calendar and its availability
From the scheduling module, create a calendar and define its availability: the days and hours when appointments can be booked, the standard duration of each block, and a maximum number of appointments per day if you need that limit. The number of calendars available depends on your plan — from 1 on Starter up to unlimited scheduling on Max.
Step 2: Connect Google Calendar (OAuth)
Authorize the connection with your Google Calendar account. With sync active, the times you already have busy in Google Calendar automatically block those same times for new WhatsApp bookings, and every appointment booked from the chat also shows up in your Google Calendar. If Google doesn't respond at that moment, the system doesn't block the booking over it — it prioritizes getting the appointment on the books.
Step 3: Turn on the agent's scheduling tools
As soon as there's an active calendar, the agent automatically mounts the tools to offer available times, book, reschedule and cancel appointments — all inside the WhatsApp conversation. The customer doesn't need to leave the chat or fill out a separate form: they ask for an appointment, the agent offers real slots and confirms.
Step 4: Configure reminders
Set the automatic reminders that go out before the appointment. If the customer is still inside WhatsApp's 24-hour window, the reminder goes out as a direct message in the conversation; once those 24 hours have passed, you need an HSM template configured on the calendar to notify them anyway, with the appointment time as a parameter of the message.
Step 5: Measure no-shows
With the flow running, review how many appointments are completed versus how many end as no-shows — the system can automatically mark an appointment as "no show" or as completed based on how much time passed without activity. It's the figure that tells you whether you need to adjust the reminder, add one closer to the appointment time, or revisit the length of your blocks.
Reminders and templates outside the 24-hour window
WhatsApp only allows free-form conversation messages within 24 hours of the customer's last message; past that window, any message you initiate needs an HSM template approved by Meta. So if your calendar has a reminder template configured, the system uses it automatically when the reminder falls outside that window, with the readable appointment time as the message parameter. If you don't have a template configured, the reminder simply doesn't go out beyond the window — worth checking if your appointments are booked well in advance. A well-timed reminder is the single biggest lever on no-show rate for most service businesses, so it's worth getting the timing and channel right before you scale bookings up.
FAQ
Do I have to use Google Calendar?
No. You can book appointments on WhatsApp without connecting Google Calendar. The connection is optional and serves to sync availability both ways if you already use Google Calendar for your team.
What if two customers try to book the same slot at once?
The system validates the available slot at the moment of confirmation and prevents double booking, rejecting the request that arrives second if the slot was already taken.
How many calendars can I have?
It depends on the plan: 1 on Starter, 5 on Pro, and unlimited scheduling on Max.
◆ next step
Connect your calendar and let Steff book appointments on WhatsApp for you.