Smart Invoice Collection System with GPT, Gmail and Google

Overview
This automation serves as an intelligent accounts receivable assistant. It ensures that overdue or pending invoices are followed up regularly, with email tone adapted based on the delay. It reduces manual tracking and maintains up-to-date client communication records in Google Sheets.

How it works

• The workflow runs monthly and scans the sheet for “Pending” or “Overdue” invoices.
• A Python node merges and filters results by overdue intervals (7, 14, 21, 28 days).
• GPT-5 generates professional, tone-adaptive reminder emails.
• Gmail sends the reminders automatically.
• Each row in the sheet is updated with a last_reminded date for audit tracking.

When to use it
Ideal for finance or operations teams managing recurring invoices. Use it to ensure timely follow-ups, maintain professionalism, and reduce overdue collections — all while keeping historical reminders in sync with your spreadsheet.