WhatsApp (Twilio) Appointment Confirmations with Google Sheets

Send WhatsApp appointment reminders and automatically handle replies in Google Sheets

This n8n workflow uses Twilio WhatsApp and Google Sheets to send daily appointment confirmation reminders for tomorrow’s bookings—and then processes inbound WhatsApp replies to confirm or cancel appointments, updating status directly in your spreadsheet.

What this workflow does

• Runs daily at 9:00 AM via an n8n schedule.
• Reads your Google Sheet (the “Citas” sheet) and selects only appointments scheduled for tomorrow that are not marked as “Cancelada” and have an empty “RecordatorioEnviado” field.
• Sends a WhatsApp reminder to each customer using the Twilio Messages API.
• Tracks delivery results: if Twilio returns success, it updates the matching row to set “RecordatorioEnviado”. If not, it appends the error details to an “Errores” sheet.
• Receives inbound WhatsApp replies via a Twilio webhook and normalizes sender phone number and message text.
• If the reply matches a confirmation or cancellation keyword, the workflow updates the appointment “Estado” in Google Sheets and replies to the customer via Twilio. For cancellations, it also sends a WhatsApp alert to the business number.
• If the reply is not recognized, it asks the customer to respond with SI or NO, and returns “OK” to the webhook request.

Use cases

• Daily automated WhatsApp appointment confirmations without manual follow-ups.
• Automated status updates in Google Sheets when customers reply “confirm” or “cancel”.
• Operational visibility via an “Errores” log when Twilio message sending fails.

Technical details

• Google Sheets: OAuth credential, Spreadsheet ID configuration, uses the “Citas” sheet columns (Nombre, Telefono, Fecha (YYYY-MM-DD), Hora, Estado, RecordatorioEnviad*), and writes errors to “Errores”.
• Twilio WhatsApp: outbound reminders through Twilio Messages API; inbound replies handled by a webhook.
• n8n workflow nodes: schedule, if, set, filter, switch, webhook, and sticky note.

*Note: the setup description references the column name “RecordatorioEnviad”; ensure your sheet columns match your configuration.