GPT-4 Gmail Outreach Automation with Google Sheets Tracking

GPT-4 Gmail Outreach Automation with Google Sheets Tracking — personalized emails, sent at scale, with reply-based lead updates

This n8n workflow pulls leads from Google Sheets, generates personalized GPT-4 HTML outreach emails, sends them via Gmail, then monitors the Gmail thread for replies—updating booking status and reply details back into your spreadsheet.

What this workflow does

• Manually start the workflow (you can trigger it whenever you’re ready to run a batch).
• Read and validate lead rows from your Google Sheets. If a lead’s email address is invalid, it logs the record to a separate Google Sheets tab.
• Filter out already-booked leads by checking Booking Status; rows marked BOOKED are skipped.
• Generate outreach content with OpenAI (GPT-4): for each remaining lead, the workflow sends lead details to OpenAI and expects a JSON response containing an email subject and HTML body.
• Send via Gmail and store the resulting Gmail thread ID for follow-up tracking.
• Check for replies: after waiting briefly, it fetches the sent Gmail thread and looks for a reply snippet that contains “Yes”.
• Update Google Sheets: if “Yes” is detected, it extracts reply details and sets the lead to BOOKED.
• Send a follow-up if needed: if no qualifying reply is found, it sends a follow-up email, waits again, rechecks the thread, and either records reply details or marks the lead as Declined.

Use cases

• SaaS teams running outreach campaigns and tracking outcomes in Google Sheets.
• Automation engineers needing a reply-driven lead status workflow in n8n.
• Operators who want GPT-4 personalization while keeping all tracking centralized in Sheets.

Technical details

• Google Sheets (source leads + outreach-tracking destination, including an invalid-email logging tab)
• Gmail with OAuth2 (send email, retrieve thread by thread ID)
• OpenAI / GPT-4 to generate subject + HTML body from lead data
• n8n nodes referenced: if, set, code, wait, gmail, and a sticky note

Setup note: add Google Sheets credentials for both spreadsheets, update document IDs and tab names, add Gmail OAuth2, and adjust the initial recipient settings as required.